Kaushik Bhagawati

Relative Performance of Plant Cultivars under Respective Water Deficit Adaptation Strategies: A Case Study

All plants exhibit tolerance to stress due to external environmental factors, but with interspecies variation in intensity. The objective of the study was to comparatively evaluate morphological and anatomical modification in different plant cultivars under similar water stress condition and their possible impact on physiological processes affecting their growth performance. The investigation was done in terms of morphological modifications, change in leaf anatomy, water status and productivity. The experiment was done under rainfed condition in northeastern India in three selected cultivars of Gladiolus. All parameters were measured using standard procedures. Stomatal density was found to decrease with water stress with lowest value in cultivar Aarti (122.2 mm -2 ) while stomatal size (length=7.3µm and breadth=7.00µm) and pore size (3.66µm2) was found to be highest in cultivar Aarti that account for its better photosynthesis rate and growth. The thickness and number of epidermal cells were found to be highest in Aarti that help them to comparatively better amelioration of moisture stress effect. The cultivar Aarti also had higher numbers and size of xylem and phloem that indicate greater unloading of carbohydrate to sink region following increase of sink size. The highest water saturation deficit was found in cultivar Apollo (36.02%) that account for its decline in stomatal conductance, reduction of stomatal size, transpiration and saturation deficit. Comparatively higher leaf area duration (116 days) and net assimilation rate (1.62 g cm-2day-1x10-3) of cultivar Aarti attributed to its higher biomass production with larger spike size with good numbers of flowers. The highest marketable spikes (71111.11 per ha) was found in cultivar Aarti which might be due to its comparatively less deviation, during stress condition, from normal morphological and anatomical characteristics. The tolerant cultivars are those that can adapt to the change without much change in their normal growth. And the responses of those species are commercially acceptable that promote adaptation without compromising much with the plant growth and crop production.

Seasonal Calendar and Gender Disaggregated Daily Activities of Indigenous Galo Farmers of Eastern Himalayan Region of India

Seasonal calendar and daily farming activities are vital in understanding the farming system of a community and identifying the period of intensive agriculture and lean period for better resources management and planning. The objective of the current study was to evaluate seasonal calendar and gender disaggregated daily activities of indigenous Galo farmers of Arunachal Pradesh. Phenomenological approach was used to understand the system as the native farmers perceive it. The result reveals the rice-based farming system of the tribe with seasonal calendar of major crops that is guided by the climate of the location. Also, it was found that farming is a family activity of the community with well defined task for each family member based on gender. Women play a major role in the farming and also have vital responsibility in preservation and conservation of indigenous local crop varieties and seeds for next season. Generally it was seen that the labor burden of tribal women exceed than that of their male counterpart. Though the farmers seem to remain in the field throughout the year, their involvement in agricultural activities is actually very low. Monocropping nature of farming, long duration crop varieties and excessive dependence on natural factor leads to poor production and productivity of crops. The seasonal calendar may help the researchers and policy makers to understand the specific need of farmers and device tailored measures for sustainable development of the farming sector and livelihood improvement of the specific community under study. Article History

Rainfall Trend and Variability Analysis of Sub-Tropical Hills of Arunachal Pradesh in Northeastern Himalayan Region of India

The climate change especially the changes in rainfall pattern is most crucial for Himalayan region as it leads to changes in river runoff and consequently affecting environment, agricultural productivity and human livelihood downstream. Current study aims to evaluate the rainfall trend and variability in the highest rainfall recipient sub-tropical hill regions of Arunachal Pradesh in Northeastern Himalayan region of India. Sen’s estimator is used for trend analysis and Mann-Kendall test to determine significance of the trend. The 37 years (1979-2015) data reveals no clear and consistent trend of average annual rainfall. But a wide inter and intra seasonal variation in the monthly rainfall has been observed. Also a significant shift in rainfall during pre-monsoon and Southwest monsoon was noticed leading to change in forest and agricultural growing seasons, mid-season dry spell during July and increase in extreme rainfall events during August, September and October. The trend analysis of rainfall will help in prediction of future climate scenarios in this Himalayan region and to understand the impact of climate change.