Convolvulaceas weeds chemical control in sugar cane

Abstract

Some Convolvulaceas can cause serious damage to the sugarcane crop. In addition, can interfere on cultural practices, in mechanical harvesting, quality reducing and productivity. The aim of this estudy was verify effectiveness of some herbicides applied in pre-emergence of sugarcane culture in the absence or presence of straw, on control of six species of convolvuluses. The experimental was a completely randomized design, in a factorial with three replications, six species of Convolvulaceas (Ipomoea grandifolia, I. hederifolia, I. nil, I. purpurea, I. quamoclit and Merremia cissoides) submitted the application of herbicides imazapic (245 g ha^-1), diuron + hexazinona (1770 + 330 g ha^-1) and clomazone + hexazinona (720 + 180 g ha^-1), in the absence and presence of cane straw. The combinations diuron + hexazinone and clomazone + hexazinone were effective in control the species Ipomoea grandifolia, Ipomoea hederifolia, Ipomoea nil, Ipomoea purpurea, Ipomoea quamoclit and Merremia cissoides, and the control was slightly increase in the presence of straw (12 t ha^-1).