Effect of dose and time of imazethapyr on weed and yield in summer season blackgram (Vigna mungo L.)

A field experiment was conducted to study the effect of dose and time of imazethapyr on weed and yield in the summer season black gram. The predominant weed species in the experimental field were Eleusine indica, Amaranthus viridis, Commelina benghalensis, Alternanthera sessilis etc. The minimum weed population was observed with two-hand weeding at 20 and 40 DAS which was closely followed by imazethapyr @ 100 g a.i. ha^-1 at 25 DAS and imazethapyr @ 75 g a.i. ha^-1 at 15 DAS. Imazethapyr 100 g a.i. ha^-1 at 25 DAS recorded the pod length, number of seeds pod^-1, test weight, harvest index, seed and stover yield. Application of imazethapyr @ 100 g a.i. ha^-1 at 25 DAS gave a higher B:C ratio (1.03) as compared to two-hand weeding at 20 and 40 DAS.