Weed dynamics and productivity of spring maize under different tillage and weed management methods (Sorghum bicolor L. Var. Speedfeed).

A field experiment was conducted during spring season of 2013 on sandy loam soil at Rampur, Chitwan, Nepal to study the effect of tillage and weed management methods on weeds dynamics and productivity of spring maize (Zea mays L.). Two tillage methods namely zero and conventional and six weed management methods namely weedy check, weed free, atrazine 1.5 kg/ha as pre emergence, atrazine and glyphosate as pre emergence, atrazine pendimethalin as pre emergence and atrazine and one hand weeding (HW) at 40 Days after sowing were tested in a strip plot design with three replications. Total weed density and dry weight recorded in conventional tillage were significantly higher than that of zero tillage at almost all growth stages. The tank mixed application of atrazine with glyphosate was found significantly more effective than with pendimethalin and Hand Weeding at 40 Days after sowing. The grain yield of maize was not affected significantly by tillage methods but it was lower in conventional tillage in comparison to zero tillage. The grain yields obtained in double combinations of atrazine with glyphosate (6.69 t/ ha), pendimethalin (6.24 t/ha) and HW at 40 DAS (6.48 t/ ha) were comparable to each other but significantly superior over its sole application and equally effective as weed free condition (7.18 t/ ha). Thus, the maize can be successfully cultivated in zero tillage and combination of atrazine either with glyphosate or with HW at 40 DAS as alternatives of manual weeding to achieve higher grain yield in spring season.