Vol. 10, Issue 10 (2021)

Author(s):
Y Sreeja, S Sakthivel, R Babu, PP Mahendran and K Sujatha

Abstract:
A field experiment was carried out at Agricultural Research Station, Paramakudi, Tamil Nadu during rabi season during 2017 and 2018 to study the interaction effect of irrigation and weed management strategies on total water consumed, water productivity and yield in semi-dry Direct Seeded Rice. The field experiments was laid out in split- plot design with irrigation in main plot and weed management in sub plot and replicated thrice. The main plot treatments comprises of three irrigation scheduling practices viz., I₁- Irrigation when water level drops to 10 cm below soil surface, I₂ - Irrigation when water level drops to 15 cm below soil surface, I₃ - Irrigation when water level drops to 20 cm below soil surface. In subplots six weed management treatments such as W₁ -Pre-emergence pendimethalin @ 1.0 kg.ha^-1 at 3 days after sowing (DAS) fb (followed by) one hand weeding at 30 DAS,W₂ –early post-emergence bispyribac sodium 25 g.ha^-1 at 15 DAS fb one hand weeding at 30 DAS,W₃-PE pendimethalin @ 1.0 kg.ha^-1 at3DAS fb star weeder at 30DAS, W₄- early post- emergence bispyribac sodium 25 g.ha^-1 at 15DAS fb star weeder at 30DAS,W₅-Pre-emergence pendimethalin@1.0 kg.ha^-1 at 3DAS fb early post-emergence bispyribac sodium@ 25 g.ha^-1at 15 DAS,W₆ -hand weeding twice at 20 and 40 DAS-were assigned. It was found that direct seeded rice consumed less consumptive use of water with higher water productivity. Among the irrigation scheduling, alternate wetting and drying irrigation when water level drops to 15 cm below soil surface registered higher water productivity. Higher grain yield was recorded when water level drops to 10 cm below soil surface with combination of PE pendimethalin @1.0 kg / ha at 3DAS fb EPOE bispyribac sodium@ 25 g / ha at 15 DAS.