Effect of Irrigation Scheduling and Weed Management Practices on Weed Dynamics, Water Productjvity and Performance of Direct Dry Sleeded Rice (Oryza Sativa L.)

Abstract

A field experiment was conducted at Chirrori farm of Sardar V allabhbhai Patel University of Agriculture and Technology, Meerut (U.P.) in spilt plot design. The maiD. plots in the study included four irrigation scheduling namely continuous shallow flooding irrigation at 10 kPa (II), alternate wetting drying irrigation at 20 kPa (h), alternate wetting drying irrigation at 20 kPa with irrigation after herbicide application (h) and alternate wetting drying irrigation at 20 kPa with mid-season drying ( 45 to 80 DAS irrigation at 40 kPa) (4) and sub-plot with weed management treatments i.e. weedy treatment (W 1), weed free (W2), pre-emergence Pendimethalin@ 1 kg a.i. ha"1 fb post-emergence Bispyribac-Na @ 25 g a.i. ha"1 (W3) and Propanil@ 4 kg a.i. ha"1 + Pendimethalin 1 kg a.i. ha"1 (W4). ' The study revealed that A WD irrigation (h) reduces the number of irrigation (6 nos) with the saving of 20.72 per cent irrigation water use than continuous shallow flooding (!1) without any yield penalty which is facilitating higher water productivity by 15.67 per cent. The applications of Pendimethalin 1 kg a.i. ha"1 at 3 DAS followed by Bispyribac 25 g a.i. ha"1 at 25 DAS (W3) controlled weed very effectively and produce similar yield (6.32 t ha"1) as weed free (W2) (6.67 t ha" ) and also gave maximum return Rs 2.38 Rs"1 invested. However, the study also suggested that detail study should be carried out to understand interaction of irrigation scheduling and weed management practices.