Herbigation combined with plastic film mulching to control weeds in maize (Zea mays L.) fields in the Hexi Corridor region, Northwest China

Weeds pose the greatest problem to maize production systems using drip irrigation under plastic film mulching (DIPFM) in the Hexi Corridor Region (HCR), Northwest China. Herbicide application is an imperative farming operation to control weeds. An experiment was conducted to detect the efficacy and safety of two preemergence herbicide formulations, acetochlor·atrazine·2,4-D-ethylhexyl 66% SC and S-metolachlor 96% EC mixed with atrazine 90% WG, applied by drip irrigation (DA1 and DA2, respectively) combined with functional plastic film mulching in the first irrigation event after maize sowing in the HCR. The results indicated that the efficacies of DA1 and DA2 in the three experimental seasons were similar to those of the two herbicide formulations applied by traditional soil spraying with machines (farming practice, FP). Additionally, DA1 and DA2 combined with hyaline-black-hyaline alternating double-color film mulching decreased herbicide input to the field by 44.34% and 45.44%, respectively. Phytotoxicity under DA1 and DA2 was not significant in maize seedlings at 4–6 weeks after herbicide treatment. Silage yields and most harvest indexes under the DA1 and DA2 treatments were similar to and even higher than those of the FP and weed-free treatments. Treatment with DA1 increased some yield properties, which was favorable for maize plant resistance to adverse environmental conditions. This study may serve as a technological reference for the application of herbicides in DIPFM systems for weed control, and its results provide useful information regarding the use of combined mechanical and chemical strategies to manage weeds in maize production.