浙中地区鲜食玉米上主要鳞翅目害虫的发生规律和四种化学药剂的防效及残留检测

Occurrence patterns of major Lepidoptera pests, chemical control efficacy and residue detection in fresh corn in central Zhejiang Province

中文关键词:鲜食玉米  亚洲玉米螟  草地贪夜蛾  发生规律  化学防治  农药残留

keywords:fresh maize  Ostrinia furnacalis  Spodoptera frugiperda  occurrence pattern  chemical control  pesticide residue

中文摘要:为明确草地贪夜蛾Spodoptera frugiperda入侵后鲜食玉米田鳞翅目害虫发生规律的变化，对2020—2022年浙中地区鲜食玉米上主要鳞翅目害虫进行系统调查，比较甜玉米、糯玉米和普通玉米3种玉米上主要害虫的为害差异，测定甲氨基阿维菌素苯甲酸盐、虱螨脲、氯虫苯甲酰胺和乙基多杀菌素4种化学药剂对鲜食玉米果穗上害虫的田间防效，并对乳熟期玉米果穗中药剂残留进行检测。结果表明：为害浙中地区鲜食玉米的主要鳞翅目害虫为亚洲玉米螟Ostrinia furnacalis和草地贪夜蛾，其中春、秋两季抽雄前玉米上主要害虫为草地贪夜蛾，且秋季虫量高于春季，穗期玉米上主要害虫为亚洲玉米螟；草地贪夜蛾对甜玉米心叶的为害显著高于糯玉米和普通玉米。相对于普通玉米果穗，亚洲玉米螟、草地贪夜蛾、桃蛀螟Conogethes punctiferalis和劳氏黏虫Leucania loreyi均更喜欢取食鲜食玉米果穗，但普通玉米茎秆中亚洲玉米螟的百株蛀孔数和百株虫量均显著高于甜玉米和糯玉米。4种药剂在玉米吐丝期和玉米水泡期施用对鲜食玉米果穗上害虫的防效均较好，而在9叶期之前施用对果穗上害虫的防效较差。4种药剂所有施药处理后乳熟期甜玉米和糯玉米籽粒中均未检测出残留，鲜食玉米上农药残留风险较小。

Abstract:To investigate changes in the occurrence patterns of Lepidoptera pests in fresh corn fields after the invasion of the fall army worm, Spodoptera frugiperda, a systematic investigation was of the major Lepidoptera pests in fresh corn was conducted in central Zhejiang Province from 2020 to 2022.The study comparedand the damage caused by these pests to three types of corn: sweet corn, waxy corn, and grain corn. In addition, the field control effects of four chemical pesticides (eemamectin benzoate, lufenuron, chlorantraniliprole and spinetoram) against fresh corn ear pests was evaluated, and pesticide residues in corn kernels at the milk stage were analyzed. The results showed that Ostrinia furnacalis and S. frugiperda were the major Lepidoptera pests damaging fresh corn in central Zhejiang. Before the tasseling stage, S. frugiperda was the dominant pest in both spring and autumn, with a higher population density in autumn. During the ear stage, O. furnacalis was the main pest. The damage caused by S. frugiperda to sweet corn leaf whorls was significantly greater than that observed in waxy corn and grain corn. O. furnacalis, S. frugiperda, Conogethes punctiferalis and Leucania loreyi exhibited a stronger feeding preference for fresh corn ears than for grain corn. However, the number of O. furnacalis larvae and boreholes in grain corn stems was significantly higher than in sweet corn and waxy corn. The application of the four pesticides during the silking and water-soaking stages provided effective control of fresh corn ear pests, whereas applications before the nine-leaf stage resulted in relatively poor control. No pesticide residues were detected in sweet and waxy corn kernels at the milk stage, across all pesticide treatments, suggesting that the risk of pesticide residues in fresh corn under chemical control is relatively low.