Influence of Weed Management Practices on Growth Parameters and Economics of Cowpea [Vigna unguiculata (L.) Wasp.]

Abstract

A field trial was carried out in the Kharif seasons 2007 at Junagadh Agriculture University (JAU), Junagadh, Gujarat to evaluate the impact of integrated approach of weed management on rain fed cowpea. It was found that selection of appropriate herbicides and its application in combination with cultural practices at critical period of weed growth was key factor to get elevated yield in rain fed cowpea. Till date most accepted practices among cowpea growers is single application of herbicides or go for cultural practices one hand weeding (HW) + one inter cultural (IC) at 20-25 days after sowing (DAS). This was not found sufficient to manage weeds and negatively distress the growth parameters and ultimately resulted in loss of one fourth crop yield compared to that weed free treatment. Application of (pendimethalin + 1 HW + 1 IC), (imazethapyr + 1 HW + 1 IC) and (quizalofop-ethyl + 1 HW + 1 IC)  very effective in weed control and had positive impact on plant height, plant spread, number of branch per plant, number of pods per plant and number of seeds per pods. These treatments were as good as weed free plot. These integrated weed management treatments gave broad spectrum weed control and higher gross, net return and B:C ratio. By adopting appropriate weed management practices farmer can get 3000 to 4000 net increase in return over the other treatment. So integrated weed management is better option and cowpea grower combine cultural practices with suitable pre and post herbicides like as pendimethalin, quizalofop-ethyl and imazethapyr to get similar return as weed free plot.