Effect of irrigation intervals and hybrids on growth, yield and economics of dry (Boro) rice (Oryza sativa) in New Alluvial Zone of West Bengal

A field experiment was conducted at Jaguli, Nadia, West Bengal, India, during dry (boro) season of 2017, to access the performance of 4 rice (Oryza sativa L.) hybrids (‘6129 Gold’, ‘6444 Gold’, ‘Tej Gold’ and ‘DRH 775’) under 3 irrigation intervals (1, 3 and 5-day interval) for better yield and profitable production. Irrigation intervals had significant influence on growth attributes, viz., tiller production, leaf area index and dry-matter accumulation at 63 days after transplanting (DAT), crop growth rate at 42–63 DAT, and yield components, viz., panicles/m², filled grains/panicle and test weight, of hybrids at maturity. Rice hybrids grown with irrigation at 1-day interval resulted in the highest grain yield (5.92 t/ha), which was slightly greater (2.07%) over 3-day interval and much higher (18.64%) over 5-day interval. Among the rice hybrids, ‘6129 Gold’ gave the highest grain yield and net income (5.88 t/ha and ₹33,718/ha) followed by ‘Tej Gold’ (5.57 t/ha and ₹29,088/ha), ‘DRH 775’ (5.46 t/ha and ₹27,518/ha) and ‘6,444 Gold’ (5.37 t/ha and ₹26,958/ha). Irrigation at 3-day interval in rice hybrids may be adopted in New Alluvial Zone of West Bengal owing to moderate grain yield (5.80 t/ha), higher water-use efficiency (5.02 kg/ha-mm), net income (₹33,518/ha) and benefit: cost ratio (1.70).