Impact of integrated weed management practices soil microbial count and grain yield in black gram (Phaseolus mungo L.)

Abstract

A field investigation was carried out during Kharif season in 2010 at Agronomy Department Farm, Dr.Panjabrao Deshmukh Krishi Vidyapeeth, Akola, to evaluate the effect of four herbicides (imazethapyr, pendimethalin, fenoxyprop-p-ethyl and quizalofop -p-ethyl ) applied at different rates with different time of application (pre-emergence,post emergence and combination of both) and cultural practices on soil microflora and yield of black gram (Phaseolus mungo). Data revealed that different chemicals and cultural weed control practices were exhibited their superiority over weedy check and reduced the crop weed competition by controlling the annual and broad leaved weeds. Among all the weed control treatments, pre-emergence application of pendimethalin @ 1.5 kg/ha showed higher yield per ha (10.05) and in case of in microbial study, bacterial, fungal and actinomycetes count before spraying of herbicide was non-significant but microbial count was reduced after spraying of herbicides as compared to before spraying of herbicides,as a result(before and after spraying of herbicide) pre-emergence application of imazethapyr at 75 g ha-1[(25.11, 17.10 ) ,( 19.50, 10.84) and (22.30,16.10)] showed the lower microbial count. In case of weedy check(26.90, 20.60 and 23.98) showed maximum microbial count followed by weed free (26.50, 20.30 and 22.60 ), among all the weed control practices.