Influence of irrigation scheduling and weed management practices on weed density and performance of dry direct seeded rice

A field experiment was carried out at Chirrori farm of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut (U.P.) in spilt plot design. The main plots in the study included four irrigation scheduling namely, continuous shallow flooding irrigation at 10 kPa (I1), alternate wetting drying irrigation at 20 kPa (I2), alternate wetting drying irrigation at 20 kPa with irrigation after herbicide application (I3) and alternate wetting drying irrigation at 20 kPa with mid-season drying (45 to 80 DAS irrigation at 40 kPa) (I4) and sub-plot with weed management treatments i.e. weedy treatment (W1), 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). Continuous shallow flooding irrigation at 10 kPa (I1) reduces the weed density significantly. 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-1). However, the study also suggested that detail study should be carried out to understand interaction of irrigation scheduling and weed management practices.