EFFECT OF WEEDING FREQUENCY AND POPULATION DENSITY ON THE GROWTH AND YIELD OF SESAME

Abstract

Abstract

The experiment was conducted at the Agronomy farm of Sher-e-Bangla Agricultural University to evaluate the effect of four weeding frequencies(W 1 =control, W =10, W 3 =20 and W 4 =30 days after emergence) and population densities (P =66666, P 2 =33333, P 3 =22222 and P =16666 plants/ha) on the growth and yield attributes of sesame. Weeding frequencies resulted in the increase on growth and yield attributes of sesame. The highest plant height (127.10 cm), number of branches/plant (6.33 cm) and dry weight/plant (23.63g) were obtained with 3 times weeding (10, 20 and 30 days after emergence respectively). Number of effective capsule/plant (109.60), 1000- seeds weight (3.19g), grain yield (0.98 t/ha) and harvest index (25.16%) were also found with same weeding treatment in this study. The highest plant height (136.90 cm) was recorded from the combined effect of 33333 plants/ha and three times weeding at 10, 20 and 30 days after emergence (DAE) and weeding at 10, 20 and 30 days after emergence (DAE). Weed infestation also affected the lowest plant height (109.50 cm) was found from 22222 plants/ha 4 with no weeding. But the combined effect of 16666 plants/ha with three times weeding at 10, 20 and 30 days after emergence(DAE) revealed the highest number of leaves/plant (31.80), number of branches/plant (8.30) and dry weight/plant (26.93 g). On the other hand, the highest number of effective capsule/plant (146.8), number of seeds/capsule (79.20) and 1000- seed weight (3.86g) were found with the interaction effect of 16666 plants/ha with three times on growth, yield and yield contributing characters of the crop. The highest weed significantly biomass (152.1 g/6m 2

) was observed from 16666 plants/ha with three times weeding at 10, 20 and 30 days after emergence(DAE) whereas the lowest figure was (27.55 g/6m 2 ) recorded from the plots treated with 666666 plants/ha with

1 2 one weeding at 10 days after emergence(DAE). However, the results revealed that the plots, with highest plant population weeded once, caused lower weed densities. As such, the combined treatments of 66666 plants/ha with one weeding at 10 days after emergence showed the lowest infestation, as evaluated by the lowest weed dry weight (27.55 g/6m 2 ), in compare to that of the highest (65.17 g/6m 2 ) with 16666 plants/ha and three times weeding at 10, 20 and 30 days after emergence(DAE).