Evaluation of herbicides in berseem (Trifolium alexandrinum L.) for fodder and seed production

Abstract

An investigation was conducted to study the effect of different herbicides on weed growth, green fodder and seed yields of berseem during the winter season of 2014- 15 to 2016-17 at Central Research Farm of ICAR-Indian Grassland and Fodder Research Institute, Jhansi, India. Two herbicides in seven treatment combinations viz., oxyfluorfen @ 0.02, 0.03, and 0.04 kg/ha at 0-3 days after sowing, imazethapyr @ 0.05, 0.075 and 0.100 kg/ha at 20 days after sowing, oxyfluorfen @ 0.03 kg/ha (0-3 days after sowing) followed by imazethapyr @ 0.100 kg/ha after first cut were evaluated with weed free and weedy check treatments. Application of imazethapyr @ 0.100 kg/ ha at 20 days after sowing effectively reduced the density of Coronopus didymus, Rumex dentatus, Spergula arvensis, Anagalis arvensis, Chenopodium album and other kind of weeds and recorded the lowest weed dry weight (3.29, 3.24 and 3.15 g/m2 ) at first, second and third cut of berseem. When compared to other treatments, application of imazethapyr @ 0.100 kg/ha at 20 days after sowing gave highest weed control efficiency, crop resistance index, herbicide efficiency index, weed management index and lower weed index.Weed free treatment recorded significantly highest green fodder (428.89 q/ha), seed (3.81 q/ha) and straw yield (28.05 q/ ha) of berseem. However, among the different herbicides treatments, post-emergence application of imazethapyr @ 0.100 kg/ha recorded the significantly highest green fodder (404.45 q/ha), seed (3.50 q/ha) and straw (25.79 q/ha) yields of berseem and resulted in highest net returns (Rs. 59,336/ha), benefit cost ratio (1.35) and economic efficiency (Rs. 371/ha/day).