Abstract:
In order to screen pre-emergence herbicides, which is suitable for soybean(Glycine max)-maize(Zea mays) strip intercropping system. The safety of 11 pre-emergence herbicides on maize varieties Denghai 605, Aoyu 510, Xundan 20 and soybean varieties Zhonghuang 13, Zheng 1307,Wandou 33 was determined by the greenhouse potted plant. The safety and the control effect on weeds of single and mixed treatments on soybean and maize were evaluated by field experiments. The results showed that pyroxasulfone, flumetsulam, metribuzin, S-metolachlor, pendimethalin, and flufenacet were safe to soybean and maize under the recommended dose, the thifensulfuron-methyl and acetochlor had higher inhibition on soybean variety Zheng 1307, and had no effect on the growth of other soybeans and maize. The field results showed that the total fresh weight control effects of pyroxasulfone and flufenacet on Echinochloa crus-galli, Digitaria sanguinalis, Celosia argentea and Acalypha australis were 92.1% and 88.9% at the recommended dose after 42 d. The total plant control effect and total fresh weight control effect of pyroxasulfone mixed with flumetsulam, flufenacet, metribuzin, and S-metolachlor mixed with flumetsulam on the four weeds were more than 91.6%, among them, the total fresh weight control effect of the mixture of pyroxasulfone+metribuzin 165+594 g·hm
-2 was 96.9%, and the yield increase rates of soybean and maize were 19.74% and 17.21%, respectively. The results could provide a basis for the selection of herbicides for pre-emergence in soybean-maize strip intercropping system.