BIO-EFFICACY OF GLYPHOSATE , AGAINST OTHER HERBICIDES , FOR CONTROL OF POLYGONUM CHINENS (POLYGONUM) IN TEA PLANTATIONS

摘要

Polygonum chinens is a very hard to kill weed species in Tea Plantation areas in North East India. It can result in crop loss to the extent of 50%(Rao et al.1977). It also hampers the frame formation in young teas and thereby affects their long term productivity. Glyphosate is broad spectrum post-emergence translocated herbicide which is highly effective on several perennial grasses and broad leaf weeds in Tea Plantations in India. Herbicidal cocktails were tried to increase the bio-efficacy of Glyphosate for control of Polygonum chinens against Glyphosate alone and other herbicidal mixtures. The best result was achieved by the cocktail of 2.5 L of Glyphosate and 0.6 L of 2,4 ― D Amine salt per ha. followed by a mixture of 1.5 L Glyphosate and 0.4 L Oxyfluorfen/ha. which was comparable with 3.0 L of Glyphosate per ha.