The critical period for Weed Competition in Relation to Fibre Yield of Jute (Corchorusolitorius L.)

Field experiment was carried to determine the critical time for weed competition in jute (Corchorus Olitorius L.). Two set of treatments were applied in one set weeds were allowed to infest the crop and in second set crop was kept weed free for an increasing duration of time i.e.10, 20,30,40,50 days after sowing (DAS) and up to harvest The beginning and the end of critical period of weed competition, were determined by fitting logistic and Gompertz equations, respectively. A total of 11 weed species were observed in experimental field, Grass weeds this Eleusine Indica was the dominant with relative density of 32.9 % followed by Echinochloa Colona (16.5 %). The reduction in fibre yield was recorded to be 74% when weed interference allowed up to harvest as compared to weed free period. The minimum days or start of critical period was 7 DAS which was calculate using logistic equation and end of critical period/time for weed free period was 42 DAS, which was calculated using Gompertz equation