Abstract

                                Field experiments were conducted for two consecutive rainy seasons of 2009 and 2010 at Udaipur (Rajasthan) to study the effect of weed control and sulphur application on productivity of Quality Protein Maize, associated weeds and residual effect on succeeding crops. Fifteen treatment combinations comprising five weed control (weedy check, tank mixture of atrazine at 500 g with alachlor at 1500 g, pendimethalin at 750 g, ethoxysulfuron at 15 g ha-1 as pre-emergence spray and two hand weeding at 15 and 30 DAS and three sulphur levels (00, 20 and 40 kg ha-1) were under randomized block design in three replications. Amongst the weed control treatments, pre-emergence application of atrazine at 500 g + ethoxysulfuron at 15 g ha-1 and two hand weeding at 15 and 30 DAS accounted for significant reduction in the density of all the weed flora. These two treatments accounted for 78.1 – 78.6 % reduction in total weed density and 79.2 – 79.3 % reduction in weed dry matter. Atrazine at 500 g + alachlor at 1500 g ha-1 was the next treatment in the order of superiority with 68.8 and 70.1 % reduction in weed density and dry matter. However, ethoxysulfuron caused significant injury to maize crop. Plant height at 60 and 90 DAS and at harvest increased significantly through all weed control treatments over weedy check. The crop dry matter accumulation at 30 DAS significantly increased by two hand weeding, while dry matter at 60 and 90 DAS and LAI at 55 DAS were significantly higher with two hand weeding but its result was at par with that of atrazine + alachlor. Highest grain, stover and biological yields were registered with two hand weeding; however, these were at par with those obtained by combination of atrazine + alachlor. Sulphur rates had no significant effect on weed density and dry matter.Significantly higher plant height and dry matter of crop at all growth stages and LAI at 55 DAS were found with 20 kg S ha-1, but crop dry matter at 30 DAS was significantly enhanced up to 40 kg S ha-1. Application of 40 and 20 kg S ha-1 increased grain and stover and yield by 24.7 & 14.6 and 14.4 & 8.9, respectively over control. The treatments had no adverse effect on germination per cent, shoot length and biomass of succeeding crops.

Key words : Maize Quality Protein, yield, growth, residual effect