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In the eastern part of India, rice as the most vital staple food crop supports as well the livelihood security of a vast population. Rice is mostly grown under conventional flooded culture without proper nutrient management. Crop performance, water productivity and economic profitability of rice cultivation need to be assessed under water-saving rice production methodologies with proper integrated plant nutrient management strategies using locally available low-cost nutrient sources. A field trial was conducted at the Adaptive Research Farm, Polba (58.57 m msl), Agriculture Department, West Bengal, India, during the rainy/wet seasons of 2014 and 2015 under aerobic culture, the system of rice intensification (SRI) and conventional flooded culture. The experiment was conducted to evaluate the influence of integrated plant nutrition and water-saving rice production methodologies on the crop performance and water productivity of rice and analyse the economic profitability of rice under different nutritional management and crop production methods such as aerobic culture, conventional flooded and SRI with an objective of sustainability in rice cultivation in the agroclimatic region. The results revealed that crop productivity significantly (p ≤ 0.05) varied from 4.68 t ha−1 (average yield recorded under aerobic culture) to 6.21 t ha−1 (average yield as achieved under SRI). Cultivation of rice under aerobic and conventional culture resulted in 24.6% and 20.9% yield reduction respectively as compared to SRI. Integrating 75% of the recommended dose of nitrogen (RDN) through chemicals with 25% RDN from vermicompost resulted in maximum crop productivity irrespective of crop culture. Aerobic rice culture registered maximum water economy in terms of both irrigation water productivity and total productivity. The study concludes that, for maximization of economic profitability, value cost ratio and partial factor productivity of nutrients the SRI method can be adopted along with integrated nutrient management (75% of RDN through chemicals with 25% RDN from vermicompost) in the lower Indo-Gangetic Plain Zone (IGPZ) of West Bengal, India.

Rice, the predominant food crop in India, is being grown traditionally with improper plant nutrient management mostly under the flooded situation. Recent advancement in research on crop science focuses on water-saving rice technologies for maximization in crop and water productivity under the backdrop of a shrinking water resource base for ensuring environmental and agricultural sustainability. Under this situation, an experiment was conducted in two consecutive years in a split-plot design keeping rice cultivation methodologies, viz., aerobic culture, System of Rice Intensification (SRI), and conventional flooded culture in main plots and integrated plant nutrient management (INM) treatments in sub-plots. The experiment was aimed at understanding the effects of different rice production systems and INM on nutrient content, uptake, and use efficiency. The change in soil quality parameters was also studied to understand the impact of crop establishment methods (CEM) and INM options. Significant reduction (p ≤ 0.05) in nutrient uptake and use efficiency was observed under aerobic culture compared to SRI and flooded method, although aerobic culture showed the highest physiological nitrogen use efficiency. Post-harvest available Fe status was significantly lower in aerobic rice (mean 10.39 ppm) compared to other crop establishment technologies; however, Zn status was higher in aerobic rice over the flooded situation. Although available potassium was not affected due to rice cultivation methods, available nitrogen and phosphorus status were influenced remarkably. Soil microbial quality was improved in aerobic rice in comparison to flooded rice. SRI proved to be the most efficient rice establishment method for enhancement in nutrient uptake, use efficiency, and enrichment of soil chemical and microbiological quality. Irrespective of crop culture, integrated plant nutrition in rice improved the nutrient uptake, use efficiency, and soil quality parameters. The study revealed that, under the alluvial soils of the Indo-Gangetic Plains of Eastern India, SRI can be considered as a water-saving rice production method. The method can also improve nutrient uptake, efficiency, and soil quality parameters if proper INM is adopted.

Aims: Arsenic (As) contamination in rice is at alarming level as majority of rice growing regions in India are As contaminated. Present investigation is designed to study the better understanding of the physiological and biochemical mechanisms in the amount of chlorophyll change and antioxidative enzymes activity under arsenic stress on rice variety IET-4786 (Shatabdi). Study Design: Completely Randomized Design. Place and Duration of Study: The experiment was carried out in the departmental laboratory of Plant Physiology, Bidhan Chandra Krishi Viswavidyalaya (BCKV), Mohanpur, Nadia,West Bengal during the year 2017-18. Methodology: Two classes of inorganic arsenic- As(V) in the form of Sodium arsenate (Na2HAsO4.7H2O, M. W. = 321.01) and As(III) in the form of Sodium arsenite (NaAsO2, M.W. =129.91) were added to the modified Hoagland nutrient solution@ 2.5, 5.0, 7.5, 10.0, 12.5,15.0 mg L-1concentration. After 20 days of treatment, rice seedlings under arsenate/arsenite treatments were analyzed for change in total chlorophyll content and antioxidative enzymes activity such as superoxide dismutase (SOD: EC 1.15.1.1), catalase (CAT: EC 1.11.1.6), ascorbate peroxidase (APX: EC1.11.1.11) and peroxidase (POD: EC 1.11.1.7). Results: A noticeable decrease in total chlorophyll content was observed with arsenic treatments as compared to control. Various antioxidative enzymes showed significant variable response upon exposure to As(III) and As(V). SOD activities increased at low arsenic exposure up to 7.5 mg L-1 but decreased with further increase in arsenic treatments.  APX and POD activities were increased with increase in arsenic concentrations while CAT activity displayed decreasing trend. Conclusion: The results are suggestive of differential metabolism of As(III) and As(V) in rice and could exert harmfulness in the early development stage of rice at inappropriate concentrations.

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