Effect of planting pattern and weed management on weed flora and yield of rabi sunflower.

A field study was undertaken, at S.V. Agricultural College, Tirupati during the rabi seasons of 2002 and 2003 to identify effective and economical weed management options for sunflower by studying the effect of planting pattern and weed management practices on weed flora and seed yield of rabi sunflower. Planting pattern of 45 x 30 cm recorded significantly lower weed density and biomass thus resulting in higher seed yield over 60 x 22.5 cm. Among the weed management practices, the lowest density and biomass of weeds at harvest were recorded with hand weeding (HW) twice closely followed by fluchloralin at 0.5 kg/ha+ pendimethalin at 0.5 kg/ha supplemented with one HW at 40 DAS. However, sunflower seed yield was the highest with HW twice followed by application of pendimethalin at 1.0 kg/ha. The use of planting pattern of 45 x 30 cm and managing associated weeds with HW twice at 20 and 40 DAS or pre-emergence application of pendimethalin at 1.0 kg/ha resulted in higher net returns and seed yield of irrigated rabi sunflower.