Phytosanitary Monitoring of Major Lepidopteran Pest and Their Natural Enemies in Maize Agroecosystems of Southeastern Kazakhstan

Information on the seasonal dynamics of major maize pests and naturally occurring parasitoids and predators in agroecosystems of southeastern Kazakhstan remains limited. Regional data on the seasonal occurrence of phytophagous insects and their natural enemies are needed to improve phytosanitary monitoring and support the development of environmentally oriented approaches to maize protection. The study was conducted from 2022 to 2025 in commercial maize fields in the Almaty and Zhetysu regions of southeastern Kazakhstan. Phytosanitary surveys included visual monitoring of pests and their developmental stages on selected plants, assessment of overwintering Ostrinia spp. populations in post-harvest maize residues, pheromone monitoring of the seasonal activity of Ostrinia spp. and Helicoverpa armigera, and recording of naturally occurring parasitoids and predators. The major lepidopteran pests recorded were Ostrinia spp. and H. armigera. Pheromone monitoring revealed year-to-year differences in the timing and magnitude of seasonal trap catches of both taxa. For Ostrinia spp., several periods of increased trap catches were recorded during the growing season, primarily from June to August, with the highest mean catch of 23 males per trap recorded in the third ten-day period of June 2024. For H. armigera, the timing of maximum trap catches varied among years, with the highest mean catch of 23 males per trap recorded in the first ten-day period of August 2025. Viable overwintering larvae of Ostrinia spp. were found in all 11 surveyed farms. Maize residues also contained larvae parasitized by Braconidae, tachinid pupae, and individuals showing signs of bacterial infection. During the growing season, representatives of Braconidae, Trichogrammatidae, Chrysopidae, Coccinellidae, and Tachinidae were recorded in maize agroecosystems. The findings provide a regional baseline for improving phytosanitary monitoring of maize in southeastern Kazakhstan. The observed year-to-year differences in seasonal trap catches highlight the importance of accounting for variation among individual growing seasons, while the naturally occurring parasitoids and predators recorded in this study warrant further investigation to assess their potential role in environmentally oriented maize pest management programs.