Conservation Agriculture Based Practices Affect the Weed Dynamics in Spring Maize

Abstract

In order to find out the alternative methods for the weed management in spring maize (Zea mays L.) in Terai Nepal, a study was carried out in conservation agriculture under maize-rice cropping system in Rampur, Nepal during 2013. The weeds number and dry weight were compared in tillage methods viz. conventional and no tillage; residue management viz. residue kept and removed; fertilizer doses viz. research recommended doses and farmer dose; and weed management viz. herbicide use and manual weeding. No tillage, residue kept and atrazine applied @ 1.5 kg a.i ha-1 as pre-emergence had significantly lower number and lower dry weight of grasses and broadleaf weeds as compared to conventional tillage, residue removed and manual weeding at an interval of one month. While the number and dry weight of sedges was not significantly influenced by tillage, residue and fertilizer management. Manual weeding had significantly less number and weight of sedges over atrazine use. The total number and dry weight of weeds were less in no tillage, residue retention and atrazine use over the conventional tillage, residue removed and manual weeding. It is concluded that no tillage, residue retention and atrazine use can be the alternative technologies for weed management.