Growth and yield of sunflower as influenced by weed control methods under graded levels of nutrients

摘要

A field experiment was undertaken at University of Agricultural Sciences, Bangalore to assess the feasibility of using sunflower stalks as mulch to control weeds in sunflower and to study the influence of nutrient levels on the growth and yield of sunflower. Six weed control treatments (Weedy check, Pendimethalin 1 kg ha~(-1), Pendimethalin 0.5 kg ha~(-1) + hoeing at 30 DAS, Mulching sunflower stalks @ 10 t ha~(-1), Pendimthalin 0.5 kg ha~(-1) + mulching sunflower stalks @ 5 t ha~(-1) and hoeing at20 & 30 DAS) were tested under three graded levels of nutrients (100, 75 or 50 percent of recommended NPK) in a split plot design, replicated thrice. The results revealed that application of 100 percent recommended NPK registered significantly higher growth components and seed, stalk and oil yields viz-11.82, 13.03 and 3.75 q ha~(-1), respectively, as compared to 75 or 50 percent levels. Among the weed control treatments, Pendimethalin 0.5 kg ha~(-1) +hoeing at 30 DAS gave efficient control of weeds and registered maximum seed, stalk and oil yields viz. 16.97, 18.27 and 5.48 q Irrespectively. Mulching sunflower stalks either alone (@ 10 t ha~(-1)) or in combination with pendimethalin 0.5 kg ha~(-1) (@ 5 t ha~(-1)) recorded significantly lower yields than weedy check owing to poor control of weeds and higher intensity of leaf spot disease.