Adjustment in Wet Season Rice Planting for Cropping Intensification in Coastal Bangladesh

Abstract

Major constraints to cropping systems intensification in coastal Bangladesh include the lack of fresh water for irrigation, soil salinity, excess moisture in the soils at planting time for dry season (DS) crops and the dominance of long duration wet season (WS) rice cultivars including low yield potential of local cultivars (LCs). This study aimed to find out suitable high yielding, short duration potential wet season rice cultivars to fit into the cropping system to enhance system productivity through timely planting DS non-rice and rice crops in the coastal zone. Thus, varietal trials on seven WS rice cultivars released by BRRI that have high yield potential were conducted at Dacope, Khulna and Amtali, Barguna over three years (2016-2018) to compare the performance of those cultivars with local cultivars. From these trials, BRRI dhan76 was the most preferred variety of farmers in Dacope while BRRI dhan77 was rated second in Amtali because of better performance (0.5-1 t ha^-1 yield advantage) and environmental suitability at planting and harvesting time. However, BRRI dhan54 was the most preferred variety of farmers in Amtali due to higher yield potential and shorter lifecycle (about 25-30 days) than that of LCs. The key drivers of farmer preference are (i) the cultivar performance in its own right, as well as (ii) how well they facilitate the timely planting of DS crops (Boro rice, sunflower, maize and vegetables). DS crops performed better with early sowing by escaping salinity and moisture stress. Thus, large scale dissemination of the WS transplanted aman (T. aman) cultivars may create an opportunity for enhancing total system productivity, largely through cropping system intensification. As a result, rice grain self-sufficiency and farm income will be increased notably without adverse impacts on the environment. Thus, there is potential for this approach to be replicated in other areas for cropping intensification in the coastal zone of Bangladesh.