TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
ZHANGTingTing, ZHANGGuoQiang, LIShaoKun, WANGKeRu, XIERuiZhi, XUEJun, FANGLiang, LIXiaoHong, FUJiaLe, LIJiaKai, LIANGChen, GEJunZhu, MINGBo
【Objective】This study aimed to explore the effects of combining new bio-breeding insect-resistant varieties with dense-planting precision-controlled high-yield technology on maize yield and economic benefits, and to propose the optimal cultivation mode suitable for new bio-breeding insect-resistant varieties, so as to provide the theoretical basis for optimizing the high-yield and high-efficiency cultivation system of spring maize in the Xiliaohe Plain.【Method】Through a field trial in Tongliao, Inner Mongolia from 2023 to 2024, the experiment was conducted in a split-zone design, with cultivation mode as the main zone, setting up two modes of local traditional farmer mode (FP) and dense planting precision regulation mode (DPDI); varieties as the sub-zone, four maize varieties were used, namely, Dongdan 1331 (DD1331), Dongdan 1331K (DD1331K), Youdi 919 (YD919), Youdi 919HZ (YD919HZ). Then, the impact of varietal insect resistance traits on maize yield and economic benefits under different technical models were analyzed.【Result】During a two-year trial, the insect pests in the fields of insect-resistant varieties occurred lightly, with the insect plant rate of 6.80%-9.87%; the fields of conventional varieties occurred moderately or heavily, with the insect plant rate of 22.27%-36.31%. In 2023 (insect plant rate>30%), compared with conventional varieties (DD1331, YD919), the new insect-resistant varieties (DD1331K, YD919HZ) significantly increased thousand kernel weight, thus improving maize yield (0.84%-9.31%) and economic benefits (0.3%-13.3%), whereas in 2024, when the insect plant rate was about 23%, there was no significant difference in the number of thousand kernels and the number of grains between insect-resistant varieties, and there were no significant differences in ear grain number, thousand kernel weight and yield between conventional varieties. With increasing planting density, maize yield reached its maximum at 9.0×104 or 10.5×104 plants/hm2, which was significantly higher than that at 6.0×104 plants/hm2 density, by 13.54%-19.94% and 7.48%-21.01%, respectively. The two-year average yields of the dense planting precision regulated model were significantly higher than those of the traditional farmers' model, with yield increases ranging from 13.50% to 19.19% in 2023 and from 7.03% to 14.42% in 2024. Compared with the traditional farmers' model, the economic benefits of the dense planting precision regulation model were generally improved by 0.19×104-1.02×104 yuan/hm2.【Conclusion】Insect-resistant varieties (DD1331K, YD919HZ) significantly improved yield (up to 9.31%) and economic efficiency (up to 40.3%) in years of severe insect infestation (>30% of insect plants), but did not differ significantly from conventional varieties under low insect pressure. Through optimized density (9.0×104-10.5×104 plants/hm2) and precise management of water and fertilizer, DPDI increased yields by an average of 22.18% in two years and improved economic benefits by 0.57×104 yuan/hm2 compared with the conventional mode (FP); the core principle of DPDI was that insect resistant varieties could reduce the threat of pests, decrease yield losses, reduce the use of insecticides, and lower production input costs. By increasing the production capacity of maize populations through reasonable planting density and combining drip irrigation with water and fertilizer integration for precise regulation, the yield and income of maize could be increased. The synergistic application of insect-resistant varieties and DPDI model could achieve technological superposition and further improve the ability of high and stable yield.