The experiment was conducted during the period from February to May 2015 to evaluate the yield performance of sesame as influenced by sowing methods and weeding regimes at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh.
Location and soil The experimental site was located at 24.750 N latitude and 90.500 longitude at a mean elevation of l8 m above the sea level. The area was a medium high land belonging to the Sonatola series of non–calcareous dark grey floodplain soil type under the Old Brahmaputra Floodplain (AEZ 9), (UNDP and FAO, 1988).
Climate The climate of the experimental site was subtropical. It was characterized by high temperature, high humidity, and heavy precipitation with occasional gusty winds during Kharif season (April to September) and scanty rainfall associated with moderately low temperature and plenty of sunshine during Rabi season (October to March).
Experimental treatments and design Two seed sowing methods and six weed management practices including no weeding and their interaction were used in the experiment. Sowing method includes broadcasting method and line sowing. Weed management practices-No weeding (T0), weed free (T1), one hand weeding at 15 DAS (T2), two hand weeding at 15 and 30 DAS (T3), three hand weeding at 15, 30 and 45 DAS (T4), herbicide(T5). Herbicide, Panida (Pendimethalin, 3.0 L ha-1 ) was applied as a preemergence condition at moist soil condition. Two factors experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications.
Seed collection Healthy and vigorous seeds of sesame cv. Binatil–3 were collected from the Bangladesh Institute of Nuclear Agriculture (BINA), Mymensingh.
Land preparation and fertilizer application The experimental land was ploughed with a tractor followed by harrowing to attain a desirable filth. The land was finally prepared with power tiller to ensure a good land preparation. Cowdung at the rate of 10 t ha–1 was applied during land preparation. Other fertilizers at the rate 125 kg urea ha–1, 50 kg MoP ha–1, 150 kg TSP ha–1, 20 kg gypsum ha–1 and16 kg ZnSO4 ha–1 was used for the present study. Half of urea and whole amount of all other fertilizers were incorporated into the soil as broadcast at the time of final land preparation. Rest half of urea was top dressed during flower initiation (45 DAS).
Seed sowing In line sowing method seeds were sown @ 7.5 kg ha-1, Plant to plant and row to row spacing were 6–8 cm and 25– 30 cm, respectively. Three to five seeds were sown hill–1 in line sowing. In broadcast sowing, seeds were sown haphazardly on the same day @ 8.5 kg ha-1.
Data collection Yield and yield attributes For collecting data on seed and stover yield attributes, ten plants from each plot excluding border plants outside the central 1 m2 area which was kept for taking yield data, were selected randomly. The sample plants were uprooted carefully from the soil with khurpi so that no seeds were dropped in the soil.
Statistical analysis The recorded data on various parameters under study were statistically analyzed according to the principles of experimental design to find out the variation resulting from experimental treatments. Analysis of variance was done following the Randomized Complete Block Design with the help of MSTAT–C package programme developed by Russel (1986). The mean of all the studied parameters were adjudged by Duncan’s Multiple Range Test (DMRT) at 5% level of probability (Gomez and Gomez, 1984).