Impact of Chemical Weed Control on Green Fodder Yield of Berseem (Trifolium alexandrinum L.) and Soil Environment- a Review

Berseem is a widely grown winter/rabi fodder crop in India. Thirty-eight weed species of 16 plant families were identified from different sites in India. Cichorium intybus is the dominant weed species, identified from almost all the sites. Whereas, Amaranthus viridis was positive indicator species for Rahuri; Chenopodium album negative indicator species for of Pantnagar and Ranchi; Anagallis arvensis positive indicator for Jhansi and Hissar sites. Weed infestation causes 25-50 per-cent yield (green fodder & seed) losses. Butachlor, trifluralin, fluchloralin, imazethapyr, oxyflourfen, and pendimethalin were used for the chemical control of weed flora in the berseem crop. Butachlor persists up to 100, Fluchloralin 243, Imazethapyr 90-240, Oxyflourfen 60-80, and Pendimethalin 60-200 days in soil. Butachlor has 5-24, Fluchloralin 12-46, Imazethapyr 57-71, Oxyflourfen 12-29 and Pendimethalin 55-77 days’ half-life. The application of herbicides influences soil environment by affecting soil flora and fauna. However, the chemical weed control method has environmental hazards, this is a widely accepted method due to its cost-effectiveness and timely control of weed flora. It also cut down the yield losses.