Role of Planting Patterns and Weed Control Treatments on Growth and Yield of Unpuddled Transplanted Rice (Oryza sativa L.)

Background: Weeds pose a significant biotic threat to the production of rice, hindering its growth and yield. An experimental study was carried out at Lovely Professional University, Phagwara, Punjab, India during the 2023 kharif season to investigate the impact of different planting patterns in relation to weed control treatments on weed dynamics and paddy yield of transplanted rice under unpuddled conditions. Methods: The experiment was laid out in Split Plot Design comprising of four planting patterns, viz. transplanting two rows/ridge, transplanting two rows/ridge + one in furrow, flat transplanting (unpuddled), flat transplanting (puddled) in main plots and four weed control treatments, viz. pendimethalin 0.75 kg/ha as pre-em. f.b. bispyribac 10 SC at 25 g/ha as post-em., pendimethalin 0.75 kg/ha as pre-em. f.b. penoxsulam 240 SC at 24 g/ha as post-em., pendimethalin 0.75 kg/ha as pre-em. f.b. fenoxaprop 6.7 EC at 67 g/ha, post-em., unweeded (control) in sub-plots with four replications. Result: The investigation’s outcomes revealed that the highest paddy yield (67.6 q/ha) was achieved by transplanting two rows per ridge and one in the furrow, significantly outperforming other planting patterns. Conversely, the paddy yields from flat unpuddled (60.2 q/ha) and flat puddled (59 q/ha) treatments were statistically at par. Among the weed control treatments, the sequential application of pendimethalin (0.75 kg/ha) as a pre-emergence and bispyribac sodium 10 SC (25 g/ha) as a post-emergence significantly inhibited the growth and biomass accumulation of diverse weed types, such as grasses, sedges and broad-leaved weeds resulting in significantly higher paddy yield (77.9 q/ha) in comparison to all other weed control treatments.