Efficacy of different herbicides on weed flora of berseem (Trifolium alexandrinum L.)

Abstract

A f ield experiment was conducted to identify the appropriate herbicide for weed control in berseem. Oxyfluorfen @ 0.02, 0.03 and 0.04 kg a.i./ha as preemergence; imazethapyr @ 0.05, 0.075, 0.1 kg a.i. /ha as post-emergence and a combination of oxyfluorfen @ 0.03 kg a.i. /ha followed by imazethapyr @ 0.1 kg a.i. /ha after the first cut were tested with weed free and weedy check. Post-emergence application of imazethapyr at twenty days after sowing @ 0.1 kg a.i./ha recorded significantly lowest weed intensity (4.66, 4.43 and 4.14/ m2 ), weed dry weight (3.29, 3.24 and 3.15 g/m2 ) and highest weed control efficiency (82.49, 79.14 and 70.93 %) than weedy check and other herbicide treatments at first, second and third cut. It resulted in significant increase in growth and yield attributes of berssem. Application of imazethapyr @ 0.1 kg a.i./ha surpassed other treatments except the weed free with respect to green fodder (404.45 q/ha), seed (3.50 q/ha) and straw (25.79 q/ha) yields and generated highest net monetary returns (Rs. 59,336 /ha) and benefit-cost ratio (2.35).