Effect of crop geometry, fertility level and nipping on physiological parameters in relation to productivity of sesame (Sesamum indicum)

Abstract

A field experiment was conducted during the summer seasons of 2001 and 2002 at Baruipur, West Bengal, to study the effect of crop geometry, fertility levels and nipping on physiological parameters in relation to productivity of sesame (Sesamum indicum L.) in gangetic alluvial (Entisol) soil. Sixteen treatments comprising 2 crop geometries (30 cm x 30 cm and 45 cm x 20 cm), 4 fertility levels (control; 25,8.16 and 16.6 kg; 50, 17.2 and 33.2 kg; and 75,25.8 and49.8 kg N, P and K/ha) and 2 cultural operations (no nipping and nipping) were undertaken in factorial design. Crop geometry of 30 cm x 30 cm proved superior to 45 cm ' 20 cm in enhancing physiological growth parameters, viz leaf-area index (0.394), biomass production (76.25 g/plant), crop-growth rate (0.202 g/plant/day), relative growth rate (0.028 g/g/day), net assimilation rate (0.152 g/cm²/day) and yield attributes, resulting in increased seed yield (1.48 tonnes/ha). Higher fertility with the application of 75 kg N along with 25.8 kg P and 49.8 kg/ha increased the growth and yield attributes and finally seed yield (1.61 tonnes/ha) over lower levels of fertility. Nipping the terminal bud at 25 days after sowing also improved growth parameters, viz leaf-area index (0.421 ), biomass production (76.80 g/plant), crop-growth rate (0.223 g/plant/day), relative growth rate (0.028 g/g/day), net assimilation rate (1.13 g/cm²/day); yield attributes, viz capsules/plant (80.80), seeds/capsule (67.67), and consequently seed yield (1.45 tonnes/ha) of sesame over no nipping.