Impact of tillage,plant population and mulches on weed management and grain yield of maize

Field experiments were conducted during 2006 and 2007 in peshawar,using open pollinated maize variety azam in rcb design withsplit-split plot arrangements having three factors viz.,tillage,maize populations and mulches. the tillage levels (zero and conventional) wereassigned to main plots,populations (90000,60000 and 30000 plants ha-1) to sub-plots and the mulches (weeds mulch,black plastic mulch,whiteplastic mulch and mungbean as living mulch),a hand weeding and a weedy check were allotted to sub-sub plots. data were recorded on freshweed biomass (kg ha-1),grains cob-1,1000-grain weight (g) and grain yield (kg ha-1). grain yield was 2271 kg ha-1 in zero-tillage compared to2429 kg ha-1 in conventional tillage. increasing crop population increased the yield i.e. 2055,2412 and 2483 kg ha-1 in 30000,60000,and 90000plants ha-1,respectively. however,grains cob-1 and 1000-grain weight of individual plants were affected negatively with increase in croppopulation. higher grain yield (2863 kg) was recorded in hand weeding and statistically at par with black plastic mulch (2813 kg),followed byweeds mulch (2460 kg),white plastic (2398 kg) and living mulch (2145 kg ha-1),respectively as compared to weedy check (1422 kg ha-1). zerotillage resulted in higher fresh weed biomass (183 kg ha-1) than in conventional tillage (165 kg ha-1). lower weed biomass (158 kg) was recordedin 90000 crop plants ha-1 as compared to 60000 (168 kg) and 30000 (196 kg ha-1),respectively. less fresh weed biomass was observed in handweeding (112 kg) which was at par with black plastic mulch (120 kg),followed by weeds mulch (164 kg),white plastic mulch (191 kg) andliving mulch (195 kg) as compared to check (260 kg ha-1). in light of two years study,conventional tillage with 90000 plants ha-1 along withhand weeding or black plastic mulch proved to be the best in terms of weed management and grain yield.