IBM abstract

Mathematical and statistical ecology Oral presentations Modelling nematode infestation on Tuberose (Polianthes tuberosa L.) Md.Noman, *Herojit Singh, Simpy Sarkar, K Roy, P K Sahu Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal-741252 *Presenting author Tuberose (Polianthes tuberosa L.) is cultivated in large scale in many tropical and subtropical countries including India. It is an important cash crop in India and commercial cultivation is taking place in Karnataka, Andhra Pradesh, Tamil Nadu, Maharashtra and West Bengal. During 2014-15 total area under tuberose in India was 6.82 thousand hectares producing 42.74 thousand MT and 5.93 lakh spikes (Anonymous, 2015). Comparatively low productivity in West Bengal is attributed to incidence of pests including nematodes besides other problems. Farmers are often unaware of losses caused by nematodes infestation because the damage is so subtle that it goes unnoticed or is attributed to other causes. In this study an attempt has been made to record incidences of different soil borne nematodes, model nematode incidences, assessing the relationship of nematode loads with various abiotic factors in tuberose cultivation using experimental data from the experimental field of Gayeshpur, Central Research Farm of BCKV, Nadia, West Bengal during 2014 -16. Results indicate populations of different species of nematodes start from zero, increase, reach to its plateau and then remained constant. Among the theoretical probability distributions explored to know the probability of occurrence of nematodes negative binomial and geometric distributions are found best fitted for all species except for total plant parasitic nematode which follows discrete uniform distribution. Critical values of nematode incidence for different species are calculated using the best fitted distributions which will help to make a forewarning system for farmers against nematode attack on tuberose. Keywords: tuberose; nematode; modelling; probability 98 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Neutral, lumpy and intransitive assemblages respond differently to immigration in spatially heterogeneous environments 1 *Joydeb Bhattacharyya , D.L. Roelke 2 1 Department of Mathematics, Karimpur Pannadevi College, Nadia, WB -741152, India 2 Department of Wildlife and Fisheries Science, Texas A&M University, TX-77840, USA *Presenting author Species-supersaturated phytoplankton assemblages sustained through neutrality, lumpy coexistence or intransitivity quickly loses diversity following immigration. The presence of source patches, however, may facilitate persistence of species- supersaturation in the face of invaders. We explore that notion through simulation analyses of detailed spatially explicit models depicting one- and two-dimensional systems where water circulation is governed over a range of advection and turbulent diffusion. For the one-dimensional model, when advection and turbulent diffusion are low, and when advection is high and turbulent diffusion is low, resident assemblages are more resistant to immigrants. But at intermediate rates of advection and with increases to turbulent diffusion, assemblages are more quickly impacted by immigrants. For the two-dimensional model, when advection and turbulent diffusion are low, resident assemblages are again resistant to immigrants, but only for lumpy assemblages. In contrast to the one-dimensional model, resistance to immigrants of neutral and lumpy assemblages is high when advection and turbulent diffusion are high. For both model configurations, intransitive assemblages were much more sensitive to immigrants, suggesting that intransitivity might not be as prevalent a biodiversity-sustaining mechanism in spatially heterogeneous plankton systems. 99 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Oral presentations An approach towards quantification of food web structure and ecosystem health using ecological network analysis in Hooghly estuarine system, India 1 2 *Joyita Mukherjee , Santanu Ray 1 Department of Zoology, K.C. College, Burdwan University, Hetampur, Birbhum 731124, India 2 System Ecology and Ecological Modelling Laboratory, Department of Zoology, Visva- Bharati University, Santiniketan 731235, India *[email protected] This study describes structure of food web of the Hooghly-Matla Estuarine System (HMES) including Sundarban mangroves and quantifies different indices of ecological network analysis (ENA). HMES, abode for many economically important shell and fin fishes, is exposed to various threats such as increasing salinity, deterioration of soil fertility and productivity, pollution and loss of biodiversity. ENA is applied for the HMES to model the trophic flows in 22 ecological compartments using Ecopath (a software for network analysis), integrating ecological data for the 2013-2015. ENA is performed, including a set of indices, keystoneness and trophic spectrum analysis to describe the contribution of the 22 groups to the HMES functioning. Results show that the ecotrophic efficiency of the HMES is in the range of 0.016 to 0.989. Small demersal fishes, prawns, shrimps and crabs are the most exploited groups of this ecosystem. Relative absence of top predators and low maturation level has made this system a detritus based ecosystem. Maturity of the system, organization, relative order and disorder within the system, diversity of flow of material among compartments and overhead of the system has been assessed. Biomass over Total system throughput ratio (TB/TST), Total primary production over total respiration ratio (TPP/TR), Total primary production over biomass (TPP/TB) and system omnivory index (SOI) indicate the moderate maturity level of the system. Several indices derived from ENA, such as total system throughput (TST), capacity (C), ascendency (A), redundancy (R), Finn's cycling index (FCI) and ascendency over capacity ratio (A/C) etc. are calculated and analyzed. System robustness and exergy are estimated to assess ecosystem health and compared with other tropical systems. From a holistic point of view, present study conveys fundamental information and categorizes the status of the system. Keywords: Static model; Ecopath; Mangrove; Food web; Exergy 100 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Modelling organic matter dynamics of a reclaimed and a virgin island of Sundarban mangrove wetland soils - a comparative study *Madhumita Roy , Santanu Ray 1 2 1 Brahmananda Keshab Chandra College, Department of Zoology, West Bengal State University, India. 2 Ecological Modelling Laboratory, Department of Zoology, Visva- Bharati, Santiniketan, India *[email protected] Sundarban mangrove ecosystem in India is one of the largest detritus based ecosystem in the world. However mangrove forests are disappearing at alarming rates due to various anthropogenic impacts (reclamation for aquaculture, farming, residential and industrial development). Generalized detritus dynamics models have been developed for intertidal mangrove forest and sediment soil of mangrove estuarine creeks, to make a comparative study between a reclaimed and a virgin Island. Based on the litterfall data and detail nutrient status in terms of nitrogen, we estimated the amount of litter exported from the forest annually, contributing the formation of detritus. Almost 70% of the detritus formed in the soil is being washed in the adjacent estuarine water to act as source or sink of nutrient for the primary producers of aquatic food chain. Total detrital nitrogen of the soil has been simulated, and then the models have been calibrated and validated accordingly with the help of two year’s consecutive field data. Increased detrital nitrogen values in the post monsoon months, observed from the field study denote probable accumulation of nitrogen due to anthropogenic run-off in case of the reclaimed Island. Whereas in case of virgin Island, the accumulation is due to the high rate off annual litter biomass production. Comparisons of simulated and observed results demonstrated that of soil characteristics along the estuary can be adequately modelled by accounting for plant production, litter decomposition and export to the adjacent estuarine water, and allochthonous input of minerals and organic matter. Model sensitivity analysis has been done for the forcing functions and parameters at both 10% and 20% scale. Analytical solution has also been done for these single compartment generalized models. Key words: litterfall, mangrove soils, Organic matter, Remineralisation, Simulation model, sensitivity analysis 101 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Oral presentations Assessment of ecosystem health through network analysis of pelagic-benthic coupled system in Hooghly estuary, India *Nabyendu Rakshit, Santanu Ray Systems Ecology & Ecological Modelling Laboratory, Department of Zoology, Visva- Bharati University, Santiniketan, India *Presenting Author Modern aquatic resource management is based on ecosystem approach including fish as well as different organisms. In this regard, static mass balanced modelling approach, well-grounded with realistic data, is suitable for analysing ecosystem structure and function holistically. The Hooghly Matla estuarine ecosystem with adjacent mangroves is one of the largest detritus based ecosystems of the world with great ecological importance. Recent studies reveal that this ecosystem has been degrading gradually owing to different anthropogenic factors mainly overfishing. To understand the situation, two mass-balanced network models of this ecosystem, from two different time periods (less exploited phase 1985-1990 and highly exploited phase 1998-2003) have been constructed using Ecopath with Ecosim (EwE) software. Thereafter, different network indices total system throughput (TST), redundancy (R), Finn’s Cycling Index (FCI) and ascendency over development capacity ratio (A/C) are calculated. The network indices indicate that the system is approaching towards degradation. But the indices are not able to assess the overall ecosystem organization, function and magnitude of stress imposed on system. It is well known that a ‘healthy’ ecosystem have an efficient diversity of components and flows while maintaining an insurance i.e. redundancy as protection against stress; thus a measure of ecosystem robustness can successfully be used to measure the system health. In this present work, system level assessment of robustness for these two different periods is conducted. Specifically, it has been investigated that the response of the system to overfishing and other anthropogenic stress to answer the question: how does the system robustness change as a result of exploitation? Keywords: Overfishing; Ecopath with Ecosim; Network analysis; Ascendency; Finn Cycling index 102 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Effect of refuge of susceptible prey in a food-chain system: a mathematical approach Nikhilesh Sil Department of Mathematics, Narula Institute of Technology, 81, Nilgunj Road, Agarpara, Kolkata-109 [email protected] Here we proposed an eco-epidemiological model with refuge in the susceptible prey. Holling type II functional response for the predation is considered. In this paper our main aim is to consider different competition coefficients within the prey population, which leads to the emergent carrying capacity. Dynamical behaviors of the system such as bounded ness, permanence, local and global stability of the system are studied using both analytical and numerical techniques. Refuge parameter is treated as the bifurcation parameter and study the Hopf bifurcation of the system around the coexistence equilibrium. In our numerical analysis we observe that enhancement of the refuge of the susceptible prey enhance the stability of the system. Extensive numerical simulation is performed to illustrate our analytical findings. Keywords: eco-epidemiological model, permanence, global stability, Hopf bifurcation 103 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Oral presentations Spatial dynamics of a nutrient-phytoplankton system with toxic effect on phytoplankton 1 Subhendu Chakraborty , Pankaj Kumar Tiwari , Arvind Kumar Misra , Joydev 2 3 2 Chattopadhyay 1 VKR Centre for Ocean Life, National Institute of Aquatic Resources, Technical University of Denmark, Denmark 2 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata 3 Department of Mathematics, Institute of Science, Banaras Hindu University, Varanasi * Presenting author The production of toxins by some species of phytoplankton is known to have several economic, ecological, and human health impacts. However, the role of toxins on the spatial distribution of phytoplankton is not well understood. In the present study, the spatial dynamics of a nutrient-phytoplankton system with toxic effect on phytoplankton is investigated. We analyze the linear stability of the system and obtain the condition for Turing instability. In the presence of toxic effect, we find that the distribution of nutrient and phytoplankton becomes inhomogeneous in space and results in different patterns, like stripes, spots, and the mixture of them depending on the toxicity level. We also observe that the distribution of nutrient and phytoplankton shows spatiotemporal oscillation for certain toxicity level. 104 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Bayesian approach of leopard (Panthera pardus) habitat suitability modeling with the combination of prey occupancy and landscape features at Sanjay-Dubri Tiger Reserve, Madhya Pradesh, India 1, 2 *Poushali Hazra , Shankarsan Chaudhury , R. Rajasekhar , 2 2 2 Krishnamurthy Ramesh 1 Asutosh College, 92, Shyama Prasad Mukherjee Road. Kolkata 700 026, West Bengal Wildlife Institute of India, Chandrabani, Dehradun 248 001. Uttarakhand 2 *Presenting author Environmental adaptability and high human tolerance ability of leopard (Panthera pardus) directly cause human leopard conflict which is one of the important conservation challenge in across the planet. However, accurately identifying leopard habitat in such human dominated multiuse landscape is imperative to make strong conservation strategies and that may further help to mitigate human-leopard interaction. Here we use an advanced and robust Bayesian Species Distribution model, Gaussian process (GP) to predict and map the probable suitable habitat of leopards in highly disturbed Sanjay Dubri Tiger Reserve, Madhya pradesh, India. We use both presence and absence GPS locations, along with eight Eco-geographical variable and surface occupancy of six prey species to construct habitat suitability model. In this study leopards preferred relatively higher elevation and slope as the maximum presence of leopard was highest at 700m elevation and 30º respectively. The probability of leopard presence gets high in respect to the increasing distance to human settlements, at dense and open forest. The presence of prey species Chinkara, Chital, Wild pig, Nilgai increase the probability of leopard presence in the landscape. The habitat suitability model also reviles that the tiger reserve holds 40.44% suitable, 25.92% moderately suitable and 33.63% less suitable habitats of leopard. The result of our study not only will be helpful for local managers to develop conservation strategies within the tiger reserve, but our noble modelling approach also can be implemented elsewhere for identifying suitable habitats of any illusive large carnivores. Key words: habitat suitability; Bayesian; species distribution; gaussian process 105 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Oral presentations Index based identification of savanna grasslands in Thar Desert landscape of India *Priyamvada Bagaria, Sutirtha Dutta, Y. V. Jhala Wildlife Institute of India, Dehradun *Presenting author The Thar desert landscape is the only landscape in India supporting the largest population of the critically endangered Great Indian Bustards in India. Accurate identification and demarcation of its habitat, which is grassland and savanna is of utmost importance for conservation and management of the species habitat. Classifying the huge landscape of about 30,000 Km area using conventional 2 methods of satellite image classification (supervised and unsupervised classification methods) proved to be labour intensive and time consuming. A statistical approach towards index based image segmentation was tested which proved to be a better method in terms of process repeatability. Various indices (infrared, Modified Chlorophyll Absorption Ratio Index, Mid infrared, modified soil adjusted vegetation index, moisture stress index, modified triangular vegetation index, normalised burn ratio, normalised difference built up index, normalised difference infrared index, normalised difference vegetation index, renormalised difference vegetation index, ratio vegetation index, Soil and Atmospherically Resistant Vegetation Index and transformed normalised difference vegetation index) were attached to the ground truth points. The points were grouped into grassland/savanna, shrubland, woodland, sparse vegetation/barren and agriculture. The points with their respective index values were processed in a principle component analysis for identifying significant dimensions that explained more than 95% variability in the index values. A linear discriminant function analysis was performed using three significant dimensions. The prior and posterior probabilities were generated for a sample of test points. Overall accuracies were calculated for the prediction power of the model for different combinations of grouping the training sample points. The best overall accuracy (68%) could be achieved when agriculture data was omitted from the analysis and the non-habitat classes, shrubland, woodland and sparse vegetation/barren were clubbed into one class as non habitat. Similar reflectance behaviour of the natural vegetation classes in the landscape result in overlapping index values, causing 49% of the non habitat points to be misclassified into habitat class. On comparison with the overall accuracy (56%) achieved through the tedious process of supervised and unsupervised classifications with 300 classes performed on the same data, the above mentioned statistical approach towards the index based classification model proves to be a more robust and repeatable approach. At the same time, the statistical approach negates the observer bias which may vary from person to person while allocating classes in supervised and unsupervised classification systems. A repeatable classification approach for a landscape of 106 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract national importance for the conservation of an endangered bird would contribute towards repeat interval monitoring and management. Keywords: Great Indian Bustard, Thar Desert, grassland, vegetation indices, satellite image classification Modelling the effect of budget allocation to warn people on the spread of infectious diseases 1 A. K. Misra , *Rajanish Kumar Rai , Yasuhiro Takeuchi 2 1 1 Department of Mathematics, Institute of Science, Banaras Hindu University, 2 College of Science and Engineering, Department of Physics and Mathematics, Aoyama Gakuin University, Kanagawa 252-5258, Japan. *[email protected] The emergence of any new infectious disease poses much stress on the government to control the spread of such disease. The easy, fast and less expensive way to slow down the spread of disease is to make the population be aware of its spread and possible control mechanisms. For this purpose, government allocates some funds to make public aware through mass media, print media, pamphlets, etc. Keeping this in view, in this paper, a non-linear mathematical model is proposed and analyzed to assess the effect of time delay in providing funds by the government to warn people. It is assumed that susceptible individuals contract infection through the direct contact with infected individuals; however the rate of contracting infection is a decreasing function of funds availability. The proposed model is analyzed using stability theory of delay differential equations and numerical simulations. The model analysis shows that the increase in funds to warn people reduces the number of infected individuals but delay in providing the funds destabilizes the interior equilibrium and may cause stability switches. Keywords: Epidemic model, Economic funds, Time delay, Hopf-bifurcation, Stability switches 107 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Oral presentations Guanotrophication by waterbirds in freshwater lakes: a review on ecosystem perspective *Sagar Adhurya, Santanu Ray 1 Systems Ecology and Ecological Modelling Laboratory, Department of Zoology, Visva- Bharati University, Santiniketan-731235, West Bengal, India *Presenting Author Freshwater lakes throughout the world are nowadays threatened by climate change and eutrophication. As a result, the crisis of drinking water and disease outbreak resulting from poor water quality has become a global issue for policymakers. Waterbirds are an inherent part of freshwater lake ecosystem and the effect of waterbird on lake ecosystem remains an important area of research in the last century. Many freshwater lakes throughout the globe support a huge number of waterbird congregations. Nutrients from waterbird droppings may serve as an important source of nutrients to those freshwater lakes. Waterbird can modulate the nutrient dynamics of the waterbody in two ways: (i) by changing the form of nutrient in the waterbody (nutrient cycling), (ii) by bringing nutrient from another area to waterbody (external nutrient loading). Several attempts have been taken to estimate nutrient loading by waterbirds in waterbodies and mostly relies on extrapolation from bird count. Recent approaches incorporate avian bioenergetics for nutrient loading estimation. Effects of bird faeces on water quality, the faecal nutrient content of different species, nutrient loading estimation methods, factors affecting nutrient loading by waterbirds, ways to reduce the nutrient level in the waterbody and nutrient cycling pathways of waterbird faeces in the aquatic ecosystem are reviewed in this article with a brief future perspective. The study of guanotrophication is not only important with respect to water quality maintenance but also for conservation of waterbirds and their habitat. Keywords: Guanotrophication; waterbirds; eutrophication; lake; guano 108 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Growth profile of Chaetoceros sp. and its steady state behavior with change in initial inoculum size: a modeling approach *Sayani Kundu , Sabyasachi Bhattacharya , Santanu Ray , Joydev 1 1 2 Chattopadhyay 1 1 Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, B. T. Road, Kolkata, 700108, India 2 Ecological Modelling Laboratory, Department of Zoology, Visva-Bharati, Santiniketan 731235, India *Presenting author Monitoring and analysis of the growth profile of microalgae species should be an important tool for the hatchery industries before standardizing the best yielding and the cost-effective protocol for their unit. There may be several factors are involved, which determine the nature of the growth profile; in which the volume of the initial inoculum may be one of the important factors. In addition, identification and determination of different phases (lag, log, stationary etc.) of the growth profile of microalgae may be an important part in the growth profile monitoring and analysis process for the hatchery units. In relation with these, in this paper, we have two-fold objectives: 1) whether the choice of initial inocula levels has any effects on the time to maturity of the Chaetoceros sp. 2) to model the growth profile of the species from which we can theoretically determine the lag, log, stationary and decay phases of the species at different inocula levels, based on the optical density measurement as a proxy of the biomass. The estimated values of each phase are compared through statistical tests, and a suggestion on cost effective culture technique is provided to the hatchery scientists for taking optimum management decision. Keywords: Initial inoculum; optical density; growth profile; cost-effective production; hatchery industry 109 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Oral presentations Impact of predator signals on the stability of a predator-prey system - a Z control approach *Sk Shahid Nadim , Sudip Samanta , Nikhil Pal , Ibrahim M. ELmojtaba , 1 3 4 2 5 Indranil Mukhopadhyay , Joydev Chattopadhyay 6 1 Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, B. T. Road, Kolkata, 700108, India 2 Ecological Modelling Laboratory, Department of Zoology, Visva-Bharati, Santiniketan 731235, India *Presenting author Monitoring and analysis of the growth profile of microalgae species should be an important tool for the hatchery industries before standardizing the best yielding and the cost-effective protocol for their unit. There may be several factors are involved, which determine the nature of the growth profile; in which the volume of the initial inoculum may be one of the important factors. In addition, identification and determination of different phases (lag, log, stationary etc.) of the growth profile of microalgae may be an important part in the growth profile monitoring and analysis process for the hatchery units. In relation with these, in this paper, we have two-fold objectives: 1) whether the choice of initial inocula levels has any effects on the time to maturity of the Chaetoceros sp. 2) to model the growth profile of the species from which we can theoretically determine the lag, log, stationary and decay phases of the species at different inocula levels, based on the optical density measurement as a proxy of the biomass. The estimated values of each phase are compared through statistical tests, and a suggestion on cost effective culture technique is provided to the hatchery scientists for taking optimum management decision. Keywords: Initial inoculum; optical density; growth profile; cost-effective production; hatchery industry 110 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Cyanotoxin regulation under environmental stress – A new perspective 2, 3 1 1 *Swarnendu Banerjee , Abhishek Subramanian , Joydev Chattopadhyay , Ram Rup Sarkar 2, 3 1 Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, B. T. Road, Kolkata 700108, India 2 Chemical Engineering and Process Development, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India 3 Academy of Scientific & Innovative Research (ACSIR), CSIR-NCL Campus, Pune, India *[email protected] Although cyanobacteria are responsible for a large fraction of oxygen in our atmosphere, the biggest concern to mankind is the bloom forming toxic cyanobacteria. Amongst all, Microcystis are the most widely found bloom forming cyanobacteria and the toxin it produces is known as microcystin which pose an inevitable threat to aquatic ecology and food web. Inspite of decades of research in the area, the biological role and regulatory mechanism of these toxins remains larglely unknown. Since, it is a well-known fact that environmental factors can play an important role in regulating cyanotoxin levels, understanding toxin regulation under various environmental conditions is becoming increasingly important. In this work, we use a kinetic model to gain a pathway level understanding of the regulatory behaviour of microcystin. A mechanistic integration of the metabolic events involved in microcystin synthesis, the gene regulatory network of microcystin synthetase, and their interactions with the external environment provides new perspective to the toxin regulation under nitrogen stress. We conclude that, the influx of the metabolites into the GS- GOGAT cycle which is involved in nitrogen assimilation and a delicate enzyme- substrate balance concerning microcystin synthetase can determine the toxin dynamics. Keywords: microcystin, nitrogen, GS-GOGAT cycle, kinetic modelling 111 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Oral presentations Mathematical modelling of cascading migration in a tri-trophic food-chain system Tanmay Chowdhury Mrinalini Datta Mahavidyapith, Birati, Kolkata -700051 *[email protected] Diel vertical migration is a behavioural antipredator defence that is shaped by a trade-off between higher predation risk in surface waters and reduced growth in deeper waters. The strength of migration of zooplankton increases with a rise in the abundance of predators and their exudates (kairomone). Recent studies span multiple trophic levels, which lead to the concept of coupled vertical migration. The migrations that occur at one trophic level can affect the vertical migration of the next lower trophic level, and so on, throughout the food chain. This is called cascading migration. In this paper, we introduce cascading migration in a well- known model (Hastings and Powell, Ecology 73:896–903, 1991). We represent the dynamics of the system as proposed by Hastings and Powell as a phytoplankton– zooplankton–fish (prey–middle predator–top predator) model where fish affect the migrations of zooplankton, which in turn affect the migrations of motile phytoplankton. The system under cascading migration enhances system stability and population coexistence. It is also observed that for a higher rate of cascading migration, the system shows chaotic behaviour. We conclude that the observations of Hastings and Powell remain true if the cascading migration rate is high enough. 112 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Power-law leads to a fractional order vector-borne disease transmission model Tridip Sardar Dinabandhu Andrews College, Kolkata In the last few years, fractional order derivatives have been used in epidemiology to capture the memory phenomena. However, these models do not have proper biological justification in most of the cases and lack a derivation from a stochastic process. In this present manuscript, using theory of a stochastic process, we derived a general time dependent single strain vector borne disease model. It is shown that under certain choice of time dependent transmission kernel this model can be converted into the classical integer order ordinary differential equation (ODE) system. When the time-dependent transmission follows a power law form, we showed that the model converted into a vector borne disease model with fractional order transmission. We explicitly derived the disease-free and endemic equilibrium of this new fractional order vector borne disease model. Using mathematical properties of nonlinear Volterra type integral equation it is shown that the unique disease-free state is globally asymptotically stable under certain condition. We define a threshold quantity which is epidemiologically known as the basic reproduction number (R 0). It is shown that if R0 > 1, then the derived fractional order model has a unique endemic equilibrium. We analytically derived the condition for the local stability of the endemic equilibrium. To test the model capability to capture real epidemic, we calibrated our newly proposed model to weekly dengue incidence data of San Juan, Puerto Rico for the time period 30 th April 1994 to 23 April 1995. We estimated several parameters, including the order rd of the fractional derivative of the proposed model using aforesaid data. It is shown that our proposed fractional order model can accurately capture real epidemic. 113 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Oral presentations Entropy measure as Tier-I biodiversity indicator of sustainable development goals Vishnu. M, Sarojkumar V, R. Jaisahnker* C V Raman Laboratory of Ecological Informatics Indian Institute of Information Technology and Management - Kerala Kariyavattom (PO), Trivandrum 695581, Kerala, India *[email protected] Biodiversity indices are probability distribution functions. The multitude of biodiversity indices and their seemingly conflicting nature together posits as Paradox of Plenty. Whilst all biodiversity indices convey some information, none conveys all. Nevertheless indicators of biological diversity, identified within Aichi Biodiversity targets are incorporated as integral components in Sustainable Development Goals (SDGs). Possibly due to the above paradox, we are yet to identify any Tier I indicators to assess the progress in the attainment of the Aichi Biodiversity targets. Here we present results of entropy indices measured at two time periods, to represent biodiversity within four sacred groves (Kavil Shree Maheswara Ashramam (KSMA), Shree Bhadrakali Temple (SBT), Erumakkavu (EK) and Pulikottukonam Nagar Kavu (PNK) in Trivandrum, India. Field surveys were carried out in 2015 and 2018 respectively to determine tree diversities within each grove. The true diversity, expressed as effective number of species calculated from Shannon-Wiener index was consistently higher than that estimated from Simpson index in all groves. KSMA grove was the most diverse. SBT and EK groves had almost similar entropies. The Shannon evenness for all groves was greater than Simpsons evenness. PNK showed a positive change in entropy (δE 0.23) whilst the others recorded a decrease in entropy. These were consistent with the shift in effective number of species. The results demonstrate the utility of Shannon-Wiener entropy and the true diversity values derived from it as possible Tier I indicator of biodiversity in SDGs. Keywords: Biodiversity indicator, SDGs, entropy, true diversity 114 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology (Poster presentations)

Mathematical and statistical ecology Poster presentations An interval-specific goodness-of-fit test for a general time- covariate model: An application to a field growth dataset 1 *Bratati Chakraborty , Sabyasachi Bhattacharya 2 1 Lady Brabourne College, Kolkata 2 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata Living organisms exhibit different types of growth patterns. To analyze these patterns, a variety of growth laws have been proposed over the last few decades. In ecological modeling related study, a goodness-of-fit index plays a pivotal role to determine the degree of proximity between a real life data set and a growth model. In this paper, we propose an interval-specific goodness-of-fit test for a general time- covariate growth law which is primarily introduced to capture the growth of a real life experiment on a major Indian carp Cirrhinus mrigala. The proposed test measures over all fitness as well as it is capable to identify those time intervals in which the underlying growth dynamics is in the disagreement with the model, if exists any. Thus the proposed goodness-of-fit test serves as a better technique for an advanced level research works. Our method uses the finite difference of relative growth rate variable and the related asymptotic distribution to develop the test statistics. The performance of the goodness-of-fit test is illustrated through a simulation study. An application of the proposed test to a real life fish growth data is also discussed. Keywords: Goodness-of-fit test; time covariate model; relative growth rate 116 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Assessing the impact of natural enemies in a pest-natural enemy model *Dibyendu S. Mandal, Sudip Samanta, Abdullha K., Alzahrani, Joydev Chattopadhyay Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, B. T. Road, Kolkata, 700108, India *[email protected] Recently, pest control has become a very interesting research topic because it is closely associated with agricultural and economic loss. Empirical evidence shows that insect pest is responsible for lower production in crop and in many others farming. There are several biological, physical and chemical control mechanisms. However, biological control of pests by natural enemies is the main ecosystem service supplied to agriculture around the world. According to recent data analyses we can say that an increase in the number of species of natural enemies increases the overall effectiveness of biological control of insect pests in agricultural situation. In the present paper, we consider an ecological model consisting of prey (pest) and its natural enemy as the predator. Different equilibria of the system are obtained, and their stability analysis is also studied. Hopf bifurcation of the system around the interior equilibrium is discussed. The conditions for the permanence of the system are also derived. We have demonstrated the analytical results through numerical simulations by using a set of parameter values. Here we use the bifurcation theory to show the existence and stability of positive periodic solution when the interior equilibrium losses its stability. Our results suggest that in the absence of super predator, pest and natural enemy show stable coexistence. However, in the presence of super predator, if the natural enemy is killed at a lower rate, then both pest and natural enemy coexist and above a threshold value, the natural enemy extinct from the system and pest outbreak occurs. 117 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Poster presentations Transmission dynamics of mosaic disease in Jatropha curcas plantation with time delay *Fahad Al Basir , Priti Kumar Roy , Santanu Ray 2 1 1 1 Ecological modeling laboratory, Department of Zoology Visva-Bharati, West Bengal-731235, India 2 Department of Mathematics, Jadavpur University, Kolkata 700032, India *Presenting author A mathematical model is formulated for the spread of Jatropha curcas mosaic disease, transmitted by whitefly (Bemisia tabaci), considering the primary infection as a delayed process. Existence of the equilibria and their stability has been studied through qualitative theory. The non-negativity and boundedness of solutions of the delayed system has been analysed. Stability switches of the coexistence equilibrium occur through Hopf bifurcation due to disease transmission rate and time delay. Details numerical simulations carried out based on analytical outcomes. Keywords: Jatropha curcas plant, Mosaic disease, Mathematical modeling, Time delay, Stability, Hopf-bifurcation 118 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Prediction of environmental factors and zooplankton for water quality in Bakreswar Reservoir using time-series ARIMA model 1 *Moitreyee Chakrabarty , Goutam Bandopadhyay , Santanu Ray 3 2 1 PG Department of Conservation Biology, Durgapur Govt. College, Durgapur-713214 2 Department of Management Studies, National Institute of Technology, Durgapur- 713209 3 Ecological Modelling Laboratory, Department of Zoology, Siksha Bhavana, Visva- Bharati University, Santiniketan-731234 *[email protected] Reservoirs are artificial water bodies built by construction of a dam over a river. Reservoirs are the main source of drinking water supply to rural populations. These reservoirs provide the means to utilize water in a variety of useful and efficient ways. Thus, a thorough knowledge of the ecosystem and its associated limnology is essential for proposing efficient management plans. In order to ascertain the water quality of any reservoir, predictive forecasting is necessary about the principal environmental and biotic factors controlling the reservoir ecosystem functioning. The objective of the present study was to predict a seasonal forecasting of highly correlated environmental factors and zooplankton. The present study was carried out in Bakreswar reservoir, Birbhum district, West Bengal. A autoregressive integrated moving average (ARIMA) model is used to forecast eight environmental factors (Air and water temperature, Solar irradiance, Humidity, Conductivity, Hardness, Total dissolved solid and Salinity) selected based on their high auto-correlation. Along with, a single biotic variable zooplankton assemblage (No/L) was also considered. Monthly mean data for all considered factors were used to fit the model. The results confirm the best forecasting model based on ARIMA (P,D,Q) (p,d,q) and predict that the chosen factors show remarkable seasonal variation. The present study confirms seasonality in the data set which can persist in future and thus can be utilised in framing management strategies regarding the maintenance of the reservoir health and functioning. Key words: Reservoir; ARIMA; prediction; water quality; Bakreswar 119 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Mathematical and statistical ecology Poster presentations The impact of fear effect on predator-prey interactions in tri- trophic food chain model 1 *Pijush Panday , Nikhil Pal , Sudip Samanta , Joydev Chattopadhyay 3 1 2 1 Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, B. T. Road, Kolkata 700108, India 2 Department of Mathematics, Visva-Bharati University, Santiniketan 731235, India 3 Department of Mathematics, Faculty of Sciences and Arts - Rabigh, King Abdulaziz University, Rabigh 25732, Saudi Arabia *[email protected] In the present paper, we investigate the impact of fear in a tri-trophic food chain model. We propose a three-species food chain model, where the growth rate of middle predator is reduced due to the cost of fear of top predator, and the growth rate of prey is suppressed due to the cost of fear of middle predator. Mathematical properties such as equilibrium analysis, stability analysis, bifurcation analysis and persistence have been investigated. We also describe the global stability analysis of the equilibrium points. Our numerical simulations reveal that cost of fear in basal prey may exhibit bi-stability by producing unstable limit cycles, however, fear in middle predator can replace unstable limit cycles by a stable limit cycle or a stable interior equilibrium. We observe that fear can stabilize the system from chaos to stable focus through the period-halving phenomenon. We conclude that chaotic dynamics can be controlled by the fear factors. We apply basic tools of non-linear dynamics such as Poincare section and maximum Lyapunov exponent to identify chaotic behavior of the system. Keywords: Fear effect; Chaos; Lyapunov exponent; Multiple limit cycles 120 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management (Oral presentations)

Mathematical and statistical ecology Poster presentations Potato peels as natural antioxidant in Omega-3 fatty acids enriched food supplement: a novel approach 3 1 *Abhishek Bhattacharya, Shilpa Purkait, Anwesa Bag, Rabi Ranjan 4 2 Chattopadhyay Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, Barrackpore Trunk Road, Kolkata – 700108 Omega-3 fatty acids have immense health benefits. Scientific evidences have shown that omega-3 fatty acids have cardioprotective, antiarthritic, antidiabetic and antihypertensive effects. To increase the nutritional value of food and reduce the risk of chronic diseases in recent years omega-3 fatty acids enriched oil has been added in food. But developing omega-3 fortified food is challenging because they are highly prone to oxidation. On the other hand, synthetic preservatives have accumulated evidence that they could be toxic and carcinogenic. Therefore, there has been a growing interest among the researchers to seek natural antioxidants especially from plant origin to enhance the oxidative stability of omega-3 fatty acids fortified food. In this context, an attempt has been made to evaluate the oxidation stabilization potential of phenolics of potato peels of three processing varieties of potato (Kufri Chipsona-1, Kufri Chipsona – 3 and Kufri Chipsona – 4) in omega-3 fatty acids enriched food supplement. Among the test potato cultivars, peels of Kufri Chipsona – 3 showed higher antioxidant efficacy followed by Kufri Chipsona – 4 and Kufri Chipsona – 1. A high positive correlation between total phenolic content and antioxidant activity was observed. The results provide evidence that among the test potato cultivars peels of Kufri Chipsona – 3 may serve as a potential source of natural antioxidants to enhance the shelf life of omega-3 fortified food which subsequently may also help to convert potato peels of these varieties of potato from zero value waste by-product to value added products. Keywords: Omega-3 fatty acid; Oxidative stability; Potato peels; Phenolic compounds; Natural food preservatives 122 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Genetic diversity analysis of some Darjeeling tea cultivars for developing marker-trait association 1 1,2 *Anjan Hazra , Nirjhar Dasgupta , Chandan Sengupta , Sauren Das 1 2 1 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata 700 108 2 Department of Botany, University of Kalyani, Kalyani, Nadia 741235 Tea (Camellia sinensis) is the most extensively consumed beverage leading to score as second most consumed drink after water across the world. Being an important cash- crop, it receives much attention to the scientific community. The vibrant research interest basically stands for its massive demand to health conscious people for its antioxidant and a broad spectrum therapeutic potentiality. India is the second largest tea producer country as well as exporter after China. A wide range of genomic plasticity is mandatory for its sustainability against the predicted climate change and molecular breeding technique for quality improving program. DNA based markers are the widely used system in genetic diversity assessment and molecular breeding application. Genetic variation among genotypes within a species is the key resource for this task. In present study genetic variation among 22 popular Darjeeling tea cultivars has been determined through different PCR based markers (RAPD, ISSR, SSR etc.). A total 26 RAPD, 20 ISSR, 10 QTL-SSR and 14 miRNA SSR primers were characterised among the selected genotypes. The resultant genetic diversity are useful in characterising the cultivars for their genetic fingerprinting and correlating with their respective phenotype. Finally outcome of the present study will provide valuable information to the genetic improvement program for parental selection towards screening and selection of superior tea cultivars. Keywords: tea, health beverage, genetic diversity, PCR based marker, crop improvement 123 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Oral presentations Arsenic contamination in soil: a threat for the sustainable agriculture *Arindam Chakraborty, Kiron Bhakat, Dr. Ekramul Islam 1 Department of Microbiology, University of Kalyani, Kalyani, Nadia, W.B., 741235. 1 corresponding author: [email protected], *presenting author Arsenic (As) contamination in agricultural land as well as in crop plants is a serious concern for animal health, crop production and soil fertility. Through both culture- independent and dependent molecular studies, we investigated the effect of such As-contamination on diversity and distribution of free-living diazotrophs and nifH gene expression in agricultural soil. The comparison was also made at three different set up; microbial community survey in agricultural fields having different levels of As, setting up laboratory microcosms amending different levels of As and bacterial isolates exposed to different concentrations of As. Both DNA and RNA from samples with different degrees of As level and from As exposed and unexposed bacterial isolates were extracted. Extracted RNA was converted to cDNA. Real time PCR analysis revealed elevated levels of total and nitrogen fixers in the agricultural land without As contamination history through the cultivation period than As-contaminated land. CCA also indicated the suppression of nifH gene abundance by As content. Microcosm based study revealed, under long time As exposure the bacterial activities in both enriched consortia and bulk soil were decreased with the reduction of diazotrophic relative activity. Under As exposed condition reduced nifH gene expression by the isolated bacteria was also observed. Summing up from different dimensions, our study indicated that the diversity, distribution and nifH gene expression of free-living diazotrophs is perturbed by As- content in agricultural soil which might affect the sustainable agriculture. Keywords: diazotrophs; 16S rRNA gene; nifH; real time PCR; microcosm 124 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Performance of organically grown garden pea varieties in the south Chhotanagpur plateau region of Jharkhand * Avijit Kr. Dutta and Sayan Kr. Majee Ramakrishna Mission Vivekananda Educational and Research Institute School of Agriculture and Rural Development, Ramakrishna Mission Ashrama, Morabadi, Ranchi-834008 *[email protected] The Chhotanagpur plateau of Eastern India, often considered the vegetable bowl was famous for high-quality garden pea production, but nowadays due to indiscriminate uses of agro-chemicals the quality is gradually dwindling. Besides this, the high cost concerning conventional chemical farming is out of reach to the small and marginal farmers of Jharkhand. In this context, low cost involving alternative approach of farming like organic farming, which has the potential to produce quality yield is gaining popularity. Keeping view in mind, seven commonly cultivated garden pea varieties [V1: GS-10, V2: HAEP-1, V3: HAEP-2, V4: Swarna Mukti,V5: Swarna Amar, V6: Azad Pea-3 and V7: Azad Pea-1] were grown through the application of four organically designed treatments [T 1: 1% Amritpani; T2: 3% BD-501; T3: 10% Shasyagavya and T4: Absolute Control] in the experimental farm of the institute during rabi season (2016-17) by adopting F-RBD Experimental Design. Different growth, yield, and quality attributing characters of the crop were studied and found to be significant under different treatments and varietal situations. Results revealed that V 5 is the best-performing variety in terms of green pod yield (19.55± 0.29) t.ha and T3 is the best treatment -1 for maximum pod production potential (18.34 ± 0.22) t.ha in different studied -1 garden pea varieties. However, when treatment and varietal interactions were taken into consideration, then T3V6 materialized as the best combination with green pod yield of (23.10± 0.58) t.ha . Quality attributes like TSS, starch, protein -1 and ascorbic acid content of green peas performed independently under different treatments and varietal conditions, but significantly higher values were estimated in different organic treatments than their respective control counterpart. From the findings, it may be concluded that Swarna Amar and Azad Pea-3 are highly responsive to organic farming practices in terms of their yield and quality expressions in the South Chhotanagpur plateau of Jharkhand. Keywords: Garden Pea; Pisum sativum; Organic Farming; Yield; Quality 125 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Oral presentations Genetic analyses of indigenous rice landraces from north-east Indian states revealed a divergent and a complex history 3 1,2 Debarati Chakraborty , Avik Ray 1 Department of Molecular Biology and Biotechnology, University of Kalyani Nadia, Kalyani, West Bengal,741235, India 2 Centre for Interdisciplinary Studies, Kolkata-700123, West Bengal, India 3 Center for Research in Ethnobiology, Biodiversity and Sustainablility (CEiBa), Malda- 732103, West Bengal, India North-eastern states of India, a home to multitude of ethnic-linguistic groups, is a highly bio-culturally diverse region. Rice-centric agriculture of this region is entwined with rich cultural history. As a result of divergent cultural preference, the region has nurtured a huge crop genetic diversity with highly desirable yet poorly tapped agronomic traits. In the present study 171 traditional rice landraces from Assam, Arunachal Pradesh, Mizoram, Manipur, Nagaland, Sikkim were genetically characterized with a panel of standard rice microsatellites to understand their genetic diversity and population structure. Further, combining with global dataset, we determined their subpopulation identity using both model-based and multivariate analyses. The population structure analyses revealed high differentiation [G’st(Nei) = 0.28, standardized G”st = 0.57], and the AMOVA partitioned overall variance into within-population (72%) and among population (28%) components. The rice landrace groups from different states remained at various degrees of differentiation (pairwise Fst = 0.09-0.41). Model-based clustering assigned almost all the Assam, majority of Mizoram and Sikkim accessions to aus group. Whereas, all Nagaland and one-third of Arunachal Pradesh landraces are assigned to japonica. Manipur rice accessions and the rest of landraces from Arunachal Pradesh were found to be admixed with a shared ancestry among indica, japonica, aus. The findings of such a large number of aus among Assam, Mizoram, Sikkim samples points towards an intrusion, acceptance and assimilation of aus subpopulation into local culture of these regions from contiguous states. It seems to be plausible given their geographic proximity with the primary aus growing region of Bangladesh, West Bengal, and Odisha. Likewise, japonica type grains may be a fruit of exchange among neighbourhoods. Shared ancestry could be a result of exchange and subsequent crossing of germplasms from dissimilar groups. Our study unravelled a high differentiation and a divergent genetic history of NorthEast Indian rice landraces that promoted formation of culture-specific distinct groups. It presumably enabled the management and the conservation of high agro-biodiversity of this region. 126 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Utilization of raw and ripe mango peel as a quality improver in gluten free bread making * Debasmita Pathak, Utpal Raychaudhuri, Runu Chakraborty* Department of Food Technology and Biochemical Engineering, Jadavpur University, Kolkata 700032, India *[email protected] Gluten free bakery product is in high demand today because of the increasing rate of celiac disease and other gluten-related disorders. According to recent research work, dietary fibres can form a film-like structure in gluten free dough, which improves the product quality. The aim of this research work is to improve some selected quality characteristics of sorghum and rice based gluten free bread (GFB) by adding equally mixed raw and ripe mango peel powder (MPP) at different levels (2%, 4% and 6%). In frequency sweep test both 2% and 4% levels showed a higher storage modulus (G) than loss modulus (G ) whereas at 6% level, due to excess ' '' dietary fibre in MPP, viscoelastic property of dough decreased. A similar trend of result was observed when physico-chemical and sensory properties of GFB were studied. The physical parameters (specific volume, hardness and moisture) of GFB showed a significant improvement up to 4% MPP addition level and this sample also satisfied all the sensory attributes and was accepted by panelists. Antioxidant activity was increased linearly with increasing addition level of MPP. The total phenolic and flavonoid content ranges from (0.18-1.85) mgGAE/g and (0.08-0.14) mgCE/g respectively. Thus, the overall result illustrates the importance of MPP addition in gluten-free formulation of bread and a way to recycle by-product of mango processing industry. Keywords: Gluten free bread, mango peel powder, rheology, physical parameter, antioxidant activity, sensory property. 127 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Oral presentations Root uptake and dose dependent phytotoxicity study of ZnS nanoparticles in Vigna radiate *Mala Thapa , Mukesh Singh and Abhishek Mukherjee 1 2 1,2 1 Indian Statistical Institute, Rose Villa, Giridih 815 301, Jharkhand, India 2 Department of Biotechnology, Haldia Institute of Technology, Haldia 721657, West Bengal, India *[email protected] Increasing application of nanotechnology highlights the need to clarify its interaction and phytotoxicity in crop plants. However, few researches have focused on phytotoxicity of nanomaterials but their uptake and transport mechanism by plant is still unknown. This study was to examine cell internalization and upward translocation of ZnS nanoparticles by Vigna radiata (mung bean). The dissolution of ZnS nanoparticles and its contribution to the toxicity on mung bean were also investigated. Zn content was used to compare and verify the root uptake and phytotoxicity of nanoparticles in a hydroponic system. Plants were exposed to ZnS-NPs and ZnSO4 at high and low concentration (10mg/L and 0.1mg/L) for 10 days. The root uptake and phytotoxicity were visualized by light, scanning electron, and transmission electron microscopes. At the high concentration 10mg/L of ZnS nanoparticles, mung bean biomass significantly reduced, root tips shrank, and root epidermal and cortical cells highly collapsed; soluble Zn (ZnSO4) was more toxic than the ZnS-NPs. On the other hand at lower concentration (0.1mg/L) the growth stimulatory effect of ZnS-NPs was found. Therefore, the phytotoxicity of ZnS-NPs was directly proportional to the doses used. However, translocation factors of Zn from root to shoot remained very low under ZnS-NP treatments, and were much lower than that under Zn treatments, implying that 2+ little ZnS-NP could translocate up in the mung bean in this study. Keywords: Nanoparticles; uptake; phytotoxicity; crop plants 128 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Regulation of carbohydrate metabolism and polyamines in Mungbean seedlings under salinity stress and its possible amelioration by NaCl pretreatment Papiya Saha Department of Botany, Bangabasi Morning College, 19, Rajkumar Chakraborty Sarani, Kolkata 7000 009 [email protected] Salinity stress is one of the most important factors limiting seedling growth by disrupting cellular homeostasis and uncoupling major physiological and biochemical processes. The effect of NaCl stress on growth, ions accumulation, polyamine contents and sugar metabolism in growing mungbean (Vigna radiata L. Wilczek) seedlings was investigated. NaCl stress was found to be more toxic for root growth than shoot growth. A gradual decrease in fresh weight, dry weight and water content of the mungbean seedlings were observed with increasing - concentrations of NaCl. The accumulation of Na and Cl ions increased in both + root and shoot while K+ ions decreased in shoot of the mungbean seedlings with increasing concentration of NaCl. Treatments with 50 mM, 100 mM and 150 mM NaCl caused decrease in reducing sugar but increase in non-reducing sugar content. Starch contents also declined with increasing activity of starch phosphorylase (E.C. 2.4.1.1) in both root and shoot of the stressed seedlings. Salt stress also adversely affected the activities of different carbohydrate metabolizing enzymes viz., acid invertase (E.C. 3.2.1.26), sucrose synthase (E.C. 2.4.1.13), sucrose phosphate synthase (E.C. 2.4.1.14) and different polyamine contents viz., putrescine, spermine, spermidine to variable extent. Pretreatment of mungbean seeds with sublethal dose of NaCl was however, able to overcome the adverse effects of salt stress by exhibiting significant alterations of all tested parameters, imparting better growth and metabolism in mungbean seedlings under saline environment. Keywords: Amelioration, Carbohydrate metabolism, Mungbean, NaCl, Polyamines, Pretreatment 129 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Oral presentations Distribution and enrichment of acid-leachable trace elements in surficial sediments along a typical urban river estuary and Sundarban mangrove wetland, India *Priyanka Mondal, Santosh Kumar Sarkar Department of Marine Science, University of Calcutta, 35, Ballygunge Circular Road, Kolkata, 700 019, West Bengal *Presenting Author The present study characterized the spatial distribution and ecological risk assessment of total and acid- leachable trace elements (TEs) in surface sediments (top 0 - 10cm; grain size ≤ 0.63 µm) along the Hooghly (Ganges) River Estuary and Sundarban Mangrove Wetland, eastern part of India. The positive and mixohaline estuary has global significance contributing ecological and economic services. Sediment samples were collected during ebb tide covering fourteen sampling sites of diverse environmental stresses, mangrove coverage and tidal mixing. The elements, analyzed with the help of ICPMS, exhibited wide range of variations (mg kg-1) with the following descending order: Fe(25050)> Al(16992)> Mn(517) > Zn(53)> Cu(33)> Cr(29)> Ni(27)> Pb(14) >As(5)> Se(0.37)> Cd(0.17)> Ag(0.16)> Hg(0.05). In the acid-leachable fraction, Cadmium (92%) was the most dominant followed by Pb (81%), Mn (77%), Cu (70%) and Se(58%) and are of potential hazards because of their higher susceptibility, bioavailability, and potential mobility. An abrupt increase in Ag concentration (0.80 mg kg-1) was encountered at Sajnekhali with the sediment pollution indices (Enrichment Factor (21.32), Contamination Factor (11.43) and Geo-accumulation Index (2.93) indicating moderate to severe contamination of the sediment. The mean probable effect level quotient revealed 21% probability of toxicity to benthos. The result of multivariate analyses affirms that TEs originated from both lithogenic sources as well as from anthropogenic activities (such as urban and industrial activities). Hence the authors strongly recommend regular systematic monitoring emphasizing on accurate appraisal of the potential risk of TEs for effective and sustainable future management. Keywords: Acid-leachable fraction, ecological risk assessment, Hooghly River Estuary, Sundarban Mangrove Wetland 130 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Synergistic antibacterial potential of essential oils of spices against foodborne bacteria: a novel approach 3 2 1 *Shilpa Purkait, Abhishek Bhattacharya, Anwesa Bag, Rabi Ranjan 4 Chattopadhyay Agricultural and Ecological Research Unit, Indian Statistical Institute, 203, Barrackpore Trunk Road, Kolkata – 700108 Foodborne disease is a major public health problem all over the world. To address this problem there has been a growing interest among the researchers to seek natural antimicrobial food preservatives especially from plant origin. Essential oils of spices may serve as a potential source of such compounds due to their hydrophobic nature. But the main obstacle for using them is that their high doses are required to achieve the desired antimicrobial activity which subsequently may cause negative organoleptic effects in food. One of the possible strategies to overcome this problem is to use them in combination taking the advantages of their possible synergistic interactions. In this context, the present investigation has been designed using essential oils of some commonly used spices (black pepper, cinnamon and clove) against foodborne bacteria. GC-MS analysis was performed to know the major constituents in active essential oils. Among the possible combinations tested, clove/cinnamon oil combination showed synergistic antibacterial interactions against all the studied bacteria and clove/black pepper oil combination showed synergistic interactions against B. cereus whereas other possible combinations showed additive effects against all the studied bacteria. GC-MS analysis revealed that clove oil contains eugenol and β-caryophyllene whereas cinnamon oils contains cinnamaldehyde, cinnamal acetate, linalool and eugenol as major constituents. The results provide evidence that clove/cinnamon oil combination may serve as broad spectrum antimicrobial blend in preserving food at very low concentrations overcoming the problem of negative organoleptic effects which subsequently may facilitate their use in the food industry. Keywords: Foodborne bacteria; Spices; Essential oils; Synergistic interactions; Natural food preservatives 131 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Oral presentations Spatial and seasonal trend of distribution of dissolved element fraction along the tropical urbanized estuary and their possible health risk assessment Soumita Mitra* & Santosh Kumar Sarkar Department of Marine Science, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India *[email protected] The study presented spatio-seasonal variation of trace elements in the surface water (0-5cm) of tropical Hooghly River Estuary (HRE), India and evaluated the human health risk adopting USEPA standards. The estuary was found to be low- oxygenated, mesotropic and phosphate limiting one. Heterogeneous and season- specific behaviors were reflected by majority of the elements in this fluvial environment. The concentration range (µg/l) of the elements and their relative variability showed the following decreasing order: Al (78127±11187)>Fe (55109 ± 9024) >Mn (812.79±79.82) >V (107.94±16.52)> Si (85.72±27.72)> Zn (63.88±16.53)> Cr (60.58±18.46)> Ni (41.42±10.76) >Cu (47.34±7.85)> Pb (30.49±3.02)> Co (17.18±2.78) > As (3.28±1.85) > Cd (2.07±0.98). It is worth to mention that six elements (Pb, Ni, Cr, Al, Fe and Mn) exceeded the WHO’s prescribed threshold limit of drinking water which might be attributed due to multiple anthropogenic activities. The Metal Pollution Index (MPI) values exceeded the upper threshold limit endorsing adverse impact on biota for each station. Although, the studied elements excused the non-carcinogenic risk as derived from Hazardous quotient (HQ) and Hazardous Index (HI) values, the hazardous toxic elements As, Cd, Pb and Cr exceeded the upper limit of cancer -4 risk (10 ). This is a matter of great concern which might lead to cancer for two population group, where children are more susceptible than adult. Keywords: trace elements; carcinogenic risk; human health; Hooghly River Estuary; Metal Pollution Index 132 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Effect of irrigation and mulch on leaf area index, yield and water use efficiency of strawberry *Sushanta Sarkar, Prof. S. Sarkar Department of Agricultural Meteorology & Physics, Faculty of Agriculture Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia-741252, West Bengal. *[email protected] Around the globe scarcity of fresh water and competition for it among different sectors are increasing. Despite its economic importance, the sustainability of irrigated agriculture is under threat due to increasing water scarcity (Fereres et al., 2011). One of the ways of alleviating water scarcity is by increasing the efficiency of water use (Jayakumar et al., 2017). Considering these, a field experiment was carried out during November 2016 to March 2017 with the following objectives:  To study the temporal changes on leaf area index and fruit yield.  To compute evapotranspiration and water use efficiency There were four irrigation regimes viz. surface irrigation (SI) at IW/CPE=1 and three drip irrigation regimes at 1.0 ETC, 0.8 ETC and 0.6 ETC, placed in main plots with four mulch management viz. no mulch (NM), straw mulch (SM), black polyethylene mulch (BPM) and geo textile mulch (GTM). Observations were recorded on leaf area index (LAI), fruit yield, actual evapotranspiration and water use efficiency (WUE) data were computed. Salient finding of the study are as: • Irrespective of time highest value of LAI and yield were recorded under 1.0ETc and GTM. The same was lowest under SI and NM • Degree of increase in LAI and yield against time were highest under 1.0ETc and GTM. • Maximum WUE was noted under 0.6ETC-GTM combination and it was almost 10 times lower under SI-NM combination. 2 • R value for Yield-WUE relationship was 0.78 Keyword: Leaf area index, evapotranspiration, water use efficiency 133 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management (Poster presentations)

Abstract Effect of Eucalyptus and Kadamba, as biodrainage vegetation, on soil moisture depletion pattern in new alluvial zone of West Bengal 1 *Anwesha Sarkar , Sanmay Kumar Patra 2 1 Research Scholar, Department of Soil and Water Conservation 2 Professor, Department of Agricultural Chemistry and Soil Science Bidhan Chandra Krishi Viswavidyalaya, Mohanpur- 741 252, West Bengal. *[email protected] A field experiment was conducted during September 2016 to March 2017 to study the soil moisture depletion pattern underneath locally available biodrainage vegetation in a waterlogged land of new alluvial zone of West Bengal. Two natural vegetation viz., Kadamba (Neolamarckia cadamba) and Eucalyptus (Eucalyptus sp.), including a non-vegetated area as control were selected for evaluation. The results of the study showed that all the biodrainage plantations had different potential in extracting and depleting soil water from deeper soil layers and decline in groundwater table. However, the canopy of Eucalyptus vegetation has higher efficiency in extracting the surplus soil water from deeper layers and lowering the elevated groundwater table than the Kadamba vegetation. Thus, the low-cost monoculture biodrainage potential species like Eucalyptus as partial substitution or complementary association with conventional subsurface drainage techniques could be commissioned with suitable plant geometry to tackle the sustained waterlogging problem and related environmental hazards and maintain the desired soil water regimes for timely agricultural crop production. Keywords: Biodrainage; waterlogging; water table; soil moisture 135 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Poster presentations Effect of Organic Carbon Fractions of soils under rice based cropping systems Aritra Kumar Mukherjee 1, 2* , Swayambhu Ghose 1 1 Institute of Agricultural Science, University of Calcutta, 51/2 Hazra Road, Kolkata- 700019 2 Department of Agricultural Chemistry & Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur. Nadia- 741252, West Bengal * [email protected] With the rapidly emerging interest from many sectors of society in sustainable development, there is a realization that an understanding of soil management is of fundamental importance to the debate. An essential part of the art of farming is the observation of soil quality. Maintaining or enhancing soil quality is a key factor in sustaining the soil resources of the world. Large number of crops and cropping system are followed in different soils and climatic regions of India. Information regarding some location specific cropping system were identified, giving due consideration to the bio-physical and socio-economic environment of the farmers. In some districts of West Bengal, the existing cropping systems are rice-rice, rice- fallow, rice-wheat, fruit orchard etc. these cropping systems are stable and traditional and those were evolved out by farmers through years of experience. Effect of different cropping system on soil organic pool has been poorly studied, particularly under West Bengal condition. The work is a report on rice based cropping system adopted at Baruipur Experimental Farm of Calcutta University. The studied cropping system includes rice-rice, rice-wheat and rice-fallow and perennial grassland. Results showed that cultivation of soil negatively influenced the soil organic carbon level and its fractions. Among the three systems of Rice cultivation, Rice-Wheat system seems to be better choice with respect to the status of organic carbon fractions. Key words: Organic carbon, soil quality, sustainable development 136 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Acaricidal activity of some plant extacts against Red Spider Mite, Oligonychus coffeae (Nietner) (Acarina: Tetranychidae), a major pest of tea 1 1 1* Bipanchi Deka, Mridul Sarmah, Gautam Handique and Somnath Roy 1 1 Entomology Department, Tocklai Tea Research Institute, Jorhat, Assam A study was done to establish the efficacy of some selected botanicals to control red spider mite (RSM), Oligonychus coffeae (Nietner) (Acarina: Tetranychidae), a major pest of tea crop in north east India. Nowadays tea planters are using various synthetic acaricides for controlling RSM. Frequent and indiscriminate use of synthetic acaricides may lead to various problems like development of resistance, accumulation of pesticide residues in tea crop which may have lethal effect on non-target organisms. North east India is highly bio-diverse zone consists of a great range of flora and fauna, among them many plants got different beneficial properties. As an alternative to synthetic acaricides, twelve different plant extracts viz., Cassia alata, Amphineurono pulentum, Polygonum sinensis, Ipomoea convolvulus, Alfaroa mexicana, Leonurus sibiricus, Phytolacca icosandra, Polygonum hamiltonii, Phlogacanthus thyrsiformis, Nyctanthes arbor-tristis, Duranta repens and Sapindus mukorossi were chosen to assess their acaricidal property. Adult O. coffeae were exposed to two concentrations (5% and 10% w/v) of aqueous plant extracts and their relative toxicity was calculated. Among all the tested plant extracts, S. mukorossi was more effective against adult RSM as compared to the other plant extracts which showed 100% mortality at both concentrations. Mortality increased with time in both concentrations of all plant extracts. Most of the plant extracts showed better control of O. coffeae than the commercially available neem formulation (Azadirachtin 5% EC). Hence, these plant extracts can be recommended as an effective and eco-friendly non-chemical tool to control O. coffeae. Key words: Oligonychus coffeae; plant extracts; acaricidal property 137 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Poster presentations Changes in mitochondrial enzyme functionality and the fatty acid profile of muscle of Indian major carps considering metal toxicity 1# 1* Debjit Das, Suman Bhusan Chakraborty 1 Department of Zoology, University of Calcutta, Kolkata-700019, India *Presenting author Current study aims to find interrelation between mitochondrial enzyme function and fatty acid profile in fish muscle in response to metal (Lead, Copper, Cadmium, Nickel and Zinc) accumulation. Fishes (Labeo rohita, Catla catla and Cirrhinus cirrhosus) were collected from two sites (Nalban and Diamond Harbour, India). Metal accumulation, mitochondrial enzyme activity, fatty acid composition in muscle tissues was analyzed. Diminished mitochondrial enzymes activity and altered fatty acid composition were observed in response to higher metal accumulation. Higher metal concentration in fish muscle of Nalban seems to significantly (P<0.05) affect poly and monounsaturated fatty acid content, possibly due to oxidative damage and accumulation of hazardous ROS molecules. Current study is the correlative study to illuminate the level of metal induced oxidative damage and possible consequences on cellular integrity, mitochondrial functionality and flesh quality against bioaccumulation of different metals in carp. Keywords: Indian major carps; metals; muscle mitochondrial enzymes; fatty acid; flesh quality 138 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Diverse Burkholderia sp. from arsenic rich rice fields of Nadia district solubilize zinc in isolated condition *Kiron Bhakat, Arindam Chakraborty, Dr. Ekramul Islam Department of Microbiology, University of Kalyani, Kalyani-741235, West Bengal, India *Presenting author Rice is one of the world’s leading food crops and is a major diet consumed by most of the people in the world. The current increase in the growth rate of population increases the demand for rice. To satisfy the demand, farmers are forced to cultivate rice, even in the deteriorating environment, like As-rich and Zn deficient rice fields, therefore it is becoming a challenging task to ensure nutritional and food security. More importantly, decrease in soil fertility by As contamination is largely ignored. Therefore, the issues, the arsenic (As) accumulation in rice field and the zinc (Zn) deficiency in rice plants needs to be taken into serious concern. In this regard, we hypothesized that, considering the geomicrobiology of the rice rizosphere, microbial formulation comprising of plant growth promotion (PGP), As oxidation ad Zn- mobilization might offer a valuable alternative. In this study many Zn solubilizing bacteria from As-rich environment were isolated and characterized by 16S rRNA gene sequencing. We observed prevalence of genetically distinct Burkholderia sp. among Zn- solubilizing bacteria. A comparative analysis based on Zn-solubilizing potential of few Burkholderia sp. was also performed. The strains also showed PGP traits and are able to oxidize As, thus these isolates could be exploited in the future development of biofertilizer and biofortifying agents. Keywords: rice rizosphere; Zn-deficiency; As contamination; biofertilizer; Burkholderia sp. 139 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Poster presentations Decolourisation of textile effluent and dye by filamentous cyanobacteria under varied conditions 2 1* Madhulika Gupta, Aditi Nag Chaudhuri 1,2 Lady Brabourne College P1/2, Suhrawardy Avenue, Kolkata-700017 *Presenting author The textile dyeing industry, responsible for dyeing various types of fiber, stands out among all the industries causing high pollution. The dyes are stable and difficult to be degraded due to their synthetic origin and complex aromatic molecular structures. Azo dye accounts for almost 80% of annual production of commercial dyes all over the world due to their ease of manufacturing methodology. Presence of sulphur, naphthol, vat dyes, nitrate, acetic acid, soaps, enzymes and heavy metals like copper, arsenic, lead, cadmium, mercury, nickel, cobalt, chromium and certain auxiliary chemicals make the textile effluent highly toxic. It is therefore essential to remove these pollutants from wastewaters before their final disposal. Cyanobacteria being widely distributed in the environment may serve as an effective and economic alternative for removing dyes from textile industry effluents. Decolourisation by Cyanobacteria can occur by biosorption and enzymatic degradation, or a combination of both. The effectiveness of the decolourisation techniques for the removal of the dyes depends on the dye class as well as its varying substituent groups and the physicochemical characteristics of the effluent such as temperature, pH, salt content and presence of organic pollutants. This study showed the capacity of filamentous Cyanobacteria to decolourise the textile dye and effluent under varied conditions suggesting the possibility of their application in bioremediation studies. Keywords: decolourisation; textile effluent; cyanobacteria; dyes; biosorption 140 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Production of growth promoters and antimicrobials by endophytes isolated from rice plants *Mahuya Mukhopadhyay, Shreya Chakraborty Department of Microbiology, Lady Brabourne College, Kolkata *[email protected] Plants are associated with a diverse community of microorganisms, one of them being endophytes residing within the plants. These are endo-symbiotic species, often a bacterium or a fungus that lives within a plant for at least a part of its life cycle, without causing an apparent disease. Endophytes are known to enhance host growth, nutrient acquisition and increases plants’ resistance to the pathogens. In the present study, endophytic bacteria and fungi were isolated from roots, stems and leaves of locally grown rice plants. 23 strains of bacteria were isolated and characterized. The bacterial population showed a high level of growth hormone production namely, Auxin and Gibberellin to the levels of 349µg/ml and 240µg/ml respectively. 19 strains could solubilize phosphate and 3 could fix atmospheric nitrogen and prove themselves agriculturally important. The bacterial population even showed antimicrobial activity against human pathogenic strains such as Vibrio cholerae, Pseudomonas aeruginosa, Burkholderia sepsia, Acinetobacter baumannii, Klebsiella sp. and Escherichia coli. Thus the study suggests that these microbes have huge potential to synthesize numerous novel compounds that can be exploited in pharmaceutical, agricultural and other industries. Keywords: Endophytes, growth promoters, agriculture, antimicrobials, Auxin 141 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Poster presentations A new report of anthracnose disease of Dumb Cane [Dieffenbachia daguensis Engl.] caused by Colletotrichum sp. from West Bengal M. Katakam*, B.N. Panja and J.Saha Department of Plant Pathology, B.C.K.V., Mohanpur, Nadia. *[email protected] Dumb cane [Dieffenbachia daguensis Engl.] is an economically important house plant grown in the garden of Agri-Horticultural Society of India. At the study location, anthracnose disease caused devastating damage of the foliage. Symptoms appeared as large lesions with dark brown margin and grey centres with fruiting bodies arranged in concentric manner over it. Acervuli produced were black, 247.9 – 410.8 µ in size with 2 - 3 septated setae. Conidia were hyaline, cylindrical with both ends rounded, 20.8 – 28.2 x 4.4 – 7.1µ in size. Acervuli productions were huge in the Peptone Salt Agar medium which was used as sporulation media in comparison to other media. On the medium, acervuli were 472.6 – 657.9 x 298.8 – 420.8 µ sized, light brown to black with 2 - 3 septated, tapering /pointed tipped setae. Conidia were hyaline, short cylindrical to rod shaped, sometimes constriction was observed at the centre of conidia, measuring 19.9 – 25.6 x 4.2 – 6.2µ in size. On comparison of the isolated fungus with Colletotrichum gloeosprioides and Colletotrichum capsici which were known to attack the host, it was found that acervuli and conidial characteristics of causal fungal pathogen of the present study differed from C. gloeosporiodes due to the greater dimension and also from C. capsici due to dissimilarity in spore shape and size. So, the causal fungus of presently described anthracnose disease of Dieffenbachia daguensis is being proposed as Colletotrichum sp. from West Bengal. Keywords: Anthracnose;dumb cane; ornamental; Dieffenbachia sp. 142 5 India Biodiversity Meet – 2018 th Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract A study on different Boron fractions in some selected soils of old alluvial zone of West Bengal *Prashanta Barman, Arup Sen and Kallol Bhattacharyya Department of Agricultural Chemistry & Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal – 741252, Telephone: 7602329497, *[email protected] The dissertation work was undertaken to study the characterization of boron in some selected soils of Old Alluvial zone of West Bengal. 15 series of soil sample were collected randomly and analyzed to study the status of B and its different fractions (including total and available B) and the relationship between different B fractions. The relationship between different B fractions with soil properties was also studied. The available B (hot water extractable) recoveries from all the selected soils were in low to deficient ranges (0.38±0.17 mg kg soil) and total B recoveries were ranged from -1 60.23-135.12 mg kg soil. The recoveries of different B fractions from the selected soils -1 were observed within ranges of 0.18-0.89 (readily soluble B), 0.22-1.82 (specifically adsorbed B), 0.55-2.56 (oxide bound B), 0.53-2.66 (organically bound B) and 55.88- 130.21 (residual B) mg kg . The hot water extractable B was significantly correlated -1 with the recoveries of total B, residual B, specifically adsorbed and readily soluble B. Other B fractions in soil like readily soluble B, specifically adsorbed B, oxide bound B, organically bound B, residual B and total B were significantly correlated with each other in major occasions excepting the relationship of Org_B with HWS_B, RS_B and Sp_B. The HWS_B was significantly and negatively correlated with soil pH, positively with soil organic matter, available N, P and K. The RS_B was significantly and positively correlated with pH, organic C, clay, available P and negatively with amorphous Al, available Fe. The recoveries of other B fractions were significantly and positively correlated with pH, clay, available N, P, K and negatively with Mn_O, available Mn and Fe in most of the cases. The total and residual B recoveries from the selected soils were observed to increase with increasing soil depth although the other B fractions either decreased or remain unchanged. Keywords: Boron, readily soluble B, specifically adsorbed B, oxide bound B, organically bound B, residual B 143 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Poster presentations Microbial biomass and enzyme activities in submerged rice soil amended with vermicomposted tannery waste sludge and cow dung manure Priyanka Chakraborty, Sampad Sarkar, Pradip Bhattacharyya. Agricultural and Ecological Research Unit, Indian Statistical Institute, Giridih, Jharkhand We studied the suitability of vermicomposted tannery waste sludge (VTWS) application to submerged rice paddies in the perspective of metal pollution hazards associated with such materials. Experiments were conducted on rice grown under submerged condition, at the Indian Statistical Institute, Giridih farm. The treatments consisted of Control; 10 t/ha (1:1) (VTWS: CDM)+ urea (30 kg N ha ); 20 t/ha (1:1) -1 (VTWS: CDM); 10 t/ha (3:1) (VTWS: CDM)+ urea (30 kg N ha ), 20 t/ha (3:1) -1 (VTWS: CDM), CDM vermi-10 t/ha + urea (30 kg N ha ); CDM vermi-20 t/ha and -1 Fertilizer (at 60:30:30 NPK kg ha through urea, single superphosphate and muriate -1 of potash respectively). Soil microbial biomass-C (MBC), MBC as percentage of organic-C (ratio index value, RIV), urease and acid phosphatase activities were higher in CDM-vermi (CDMV) than VTWS-treated soils, due to higher amount of biogenic organic materials like water soluble organic carbon, carbohydrate and mineralizable nitrogen in the former. The studied parameters were higher when urea was integrated with CDMV or VTWS, compared to their single applications. Soil MBC, urease and acid phosphatase activities periodically declined up to 60 day after transplanting (DAT) and then increased after crop harvest. The heavy metals in VTWS did not detrimentally influence MBC, urease and acid phosphatase activities of soil. In the event of long term VTWS application, changes in soil quality parameters should be monitored regularly, since heavy metals once entering into soil persist over a long period. 144 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Studies on different forms of soil quality parameters (Physiochemical microbial ecophysiological indicators and enzyme activities) and forms of potassium in mica enrich soil of Giridih district, Jharkhand Saibal Ghosh, Abhishek Mukherjee*, Pradip Bhattacharyya* Agricultural and Ecological Research Unit, Indian Statistical Institute, Giridih, Jharkhand A study was conducted to examine the different forms of potassium (K), soil microbial ecophysiological indicators and enzyme activities in mica enriched soils of Giridih district, Jharkhand. In total, 63soil samples were collected from the Tisri, Gawan and Deori blocks of Giridih district. Most of the studied soils were found to be acidic in nature. The average pH (water), pH (KCl) and total organic C were 5.98, 4.56 and 6.2 g/kg, respectively. Different enzyme activities like urease (UA), acid phosphatase (PA), dehydrogenase and fluorescein di acetate hydrolyzing activity were studied. The studied enzyme activities (mg/kg) were varied from 13.5-84.4, 104-752, 17.5-57.2 and 8.5-45.9 respectively. Microbial ecophysiological indicators like basal soil respiration(µg CO2/g soil/h at 22̊c), substrate induce respiration(µg CO2/g soil/h at 22̊c), microbial biomass carbon(mg/kg), qCO2(%), QR(%), microbial quotient(%) were varied from 9.53-21.69, 39.20-118.70, 23.79-206.40, 0.0154-0.1377, 0.087-0.389 and 0.484-3.947 respectively. All the parameters were negatively correlated with both the pH. The average water soluble, exchangeable, non-exchangeable, lattice and total K varied from 4-53 mg/kg, 18-195 mg/kg, 422-2825 mg/kg, 471-2207 mg/kg, 734- 4161 mg/kg respectively. The average percentage contribution of water soluble, exchangeable, non-exchangeable, lattice K towards total K constitute 0.8%, 2.8%, 68.2%, 28.2% respectively. Most of the K in these soils was in non-exchangeable form. The reserves of step-K and constant rate k (CR-K) were evaluated by repeated extraction of soils with boiling molar nitric acid. The reserves of step-K content were, in general, related to the content of the clay fraction of the soils. The cumulative release of non-exchangeable K by repeated extraction with boiling 1(M) HNO3, suggesting that the release of non-exchangeable K decreased with successive number of extractions. Constant rate K and step K varied from 0.24-0.83 cmol (p )/kg and 4.63- + 59.0 cmol (p )/kg. The ratio of step-K to non exchangeable K (NEK) may reflect the + mobilizable NEK reserves in soil. The ratio of step-K to NEK in the studied soils was 0.004 to 0.039, which indicates the low mobilizable NEK reserves in soil. Both water soluble and exchangeable K were low with respect to total K. Different forms of potassium were significantly and positively correlated with each other indicated existence of equilibrium between different forms of K in these soils. The degrees of correlation between water soluble K and exchangeable K was generally of the higher order. These soils showed a wider ratio of non-exchangeable to exchangeable K, 145 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Sustainable agriculture and natural resource management Poster presentations indicating the dominance of illite in clay fraction. Low available K emphasises the need for future research to optimize K fertility management to increase productivity of intensive rice based cropping systems in these soils. Effect of irrigation and mulch on leaf area index, yield and water use efficiency of strawberry 1 Sushanta Sarkar , Prof. S. Sarkar Department of Agricultural Meteorology & Physics, Faculty of Agriculture Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia-741252, West Bengal. *[email protected] Around the globe scarcity of fresh water and competition for it among different sectors are increasing. Despite its economic importance, the sustainability of irrigated agriculture is under threat due to increasing water scarcity (Fereres et al., 2011). One of the ways of alleviating water scarcity is by increasing the efficiency of water use (Jayakumar et al., 2017). Considering these, a field experiment was carried out during November 2016 to March 2017 with the following objectives:  To study the temporal changes on leaf area index and fruit yield  To compute evapotranspiration and water use efficiency There were four irrigation regimes viz. surface irrigation (SI) at IW/CPE=1 and three drip irrigation regimes at 1.0 ETC, 0.8 ETC and 0.6 ETC, placed in main plots with four mulch management viz. no mulch (NM), straw mulch (SM), black polyethylene mulch (BPM) and geo textile mulch (GTM). Observations were recorded on leaf area index (LAI), fruit yield, actual evapotranspiration and water use efficiency (WUE) data were computed. Salient finding of the study are as: • Irrespective of time highest value of LAI and yield were recorded under 1.0ET c and GTM. The same was lowest under SI and NM • Degree of increase in LAI and yield against time were highest under 1.0ET c and GTM. • Maximum WUE was noted under 0.6ETC-GTM combination and it was almost 10 times lower under SI-NM combination. • R value for Yield-WUE relationship was 0.78 2 Keyword: Leaf area index, evapotranspiration, water use efficiency 146 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata

Abstract Effect of Arsenic on pea inoculated with Arsenic tolerant rhizobium strains Tanaya Das, *Sayan Majumder, Subhas Chandra Kole Department of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur - 741252, Nadia, West Bengal, India *Presenting author Arsenic (As) is a toxic metalloid having great environmental concern due to it’s widespread impact in the biosphere (humans, other animals, plants and microorganisms). Legume plants are cultivated worldwide for human consumption and as livestock forage. The legumes-Rhizobium symbiosis is a natural phenomenon accounting for world’s highest nitrogen fixation per annum. Arsenic has injurious effect on both the symbionts at a certain concentration. When legumes are grown in arsenic affected soils, they are prone to arsenate (aerobic condition) damage. Some Rhizobium strains can resist arsenic stress to some extent by maintaining low internal arsenic concentration. In this experiment, some As tolerant Rhizobium strains were isolated and screened from pea nodules in YEM medium amended with different concentrations of arsenate. The effect of different levels of As+5 (5, 10, 20, 40 mg kg- 1) on pea plant growth and nodulation was evaluated after inoculating some of those arsenic resistant strains in a pot culture. The growth of the Rhizobium isolates decreased with increase in concentration of arsenate in YEM broth. The tolerance limits of the strains was 1500 mg l-1 of As+5. As+5 concentration of 20 mg kg-1 or more adversely affected nodule number, root, shoot and pod biomass. Arsenic accumulation in different plant parts was increased with elevated doses of arsenate. The concentration of arsenic was in the order: Root and Nodules> Shoot > Pod. Inoculation with tolerant Rhizobium strains significantly increased nodule numbers, root, shoot and pod dry weight. This study opens a wide future prospect of utilizing Arsenic-tolerant Rhizobium strains as potential biofertilizers in arsenic contaminated soils for stabilizing pulse production. Keyword: Arsenic toxicity, As-tolerant Rhizobium strains, nodulation & growth of pea 147 th 5 India Biodiversity Meet – 2018 Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata