Mohammad Ali Ehsanjoo - M.S.c. students of crop production, Shiraz University
Reza Moradi Talebbeigi - M.S.c. students of crop production, Shiraz University
Hossein Ghadiri - Prof. of crop production, Shiraz University.

Using chemical herbicides for pigweed control creates spray drift hazards and adversely affects the environment. This experiment was conducted to determine the effects of cowpea living mulch density on pigweed suppression in corn at the Experimental Farm of College of Agriculture, Shiraz University, Shiraz, Iran, (Badjgah) in two growing seasons (2008-2010). This experiment was conducted as split plot design in four replications, in which cowpea living mulch densities (7, 15, 22 and 30 plant m-2) and cowpea suppression times (30, 45, 60, 75 and 90 days after corn planting) considered as main and sub plots, respectively. Two control treatments were weed free and weedy check. Results showed that the lowest pigweed growth parameters were obtained from 30 plant m-2 of cowpea living mulch densities, when cowpea growth was terminated 90 days after corn planting. It is concluded that to pigweed suppression and to mitigate corn seed yield losses due to crop and living mulch competition, the application and suppression of cowpea as living mulch at 22 plant m-2 densities and 75 days after corn planting respectively, is recommended.

Weed Management, Herbicide and suppression