Influence of sowing dates and varieties on the yield, heat use efficiency, energy utilization and economics of summer mungbean

A field experiment conducted at Jammu (Jammu and Kashmir) during summer season of 2013 to study the influence of sowing dates and varieties on the yield, heat use efficiency, helio-thermal use efficiency, energy utilization efficiencies and economics of summer mungbean. The experiment was conducted in a split plot design consisting of four sowing dates (20^th March, 5^th April, 20^th April and5^th May)as main-plot treatments and four varieties (SML668, Samrat, Mehaand IPM 023) as sub-plot treatments. Higher grain yield (9.33 q ha⁻¹) of summer mungbean was recorded under 20^th March sowing date, which was statistically at par with 5^th April sowing but significantly higher than 20^th April and 5^th May sowing. Among the varieties, Samrat produced significantly higher grain yield (7.82 q ha⁻¹) than all other varieties except SML 668. But, the heat use efficiency (HUE), helio-thermal use efficiency (HTUE) and energy pattern was significantly higher at 20^th March than other dates of sowing. The varieties Samrat and SML 668 recorded significantly higher HUE, HTUE and energy pattern than IPM 02-3 and Meha. The highest benefit cost ratio (1.42) was recorded with 5^th April sowing date closely followed by 20^th March (1.39). The variety Samrat also registered the highest benefit cost ratio (1.07) followed by SML-668.