Green Manure Crops as Food Source: Impact on the Performance of the Migratory Beet Webworm, Loxostege sticticalis (Lepidoptera: Pyralidae)

SIMPLE SUMMARY: Green manure application is an effective management practice for enhancing soil nutrient levels and organic matter, but pest management in green manure fields has traditionally been ignored. The beet webworm, a polyphagous insect, is currently experiencing an outbreak in northern China, and represents a significant migratory pest. We conducted a comprehensive evaluation of the effects of green manure crops on beet webworm by measuring its growth, development, fecundity, and flight ability on Chenopodium album (a suitable host), as well as three major legume green manure crops in China: Pisum sativam, Vicia sativa, and Vicia villosa. Our findings indicate that V. villosa does not serve as a host plant for the beet webworm, which experiences 100% mortality during its larval stage. This indicates that the large-scale cultivation of V. villosa as a green manure crop in northern China will not increase the risk of the beet webworm outbreaks. Although the beet webworm has a significantly lower host adaptability to P. sativam and V. sativa compared to C. album, it is still well adapted to these two green manure crops. Our research provides a foundation for selecting appropriate green manure varieties and implementing effective pest control measures during their cultivation. ABSTRACT: The application of green manure is crucial for achieving sustainable agriculture and animal husbandry, but pest management is often overlooked. Conducting a risk assessment for insect pests in green manure is essential. The beet webworm, Loxostege sticticalis, a polyphagous insect, is currently experiencing an outbreak in northern China, and represents a significant migratory pest. A two-sex life table and flight mill test approach was used to comprehensively evaluate the effects of three major legume green manure crops (Pisum sativam, Vicia sativa, and Vicia villosa) on the growth, development, fecundity, and flight ability of L. sticticalis in China. Our findings indicate that L. sticticalis cannot utilize V. villosa for generational development. L. sticticalis shows reduced performance on P. sativam and V. sativa compared to its suitable host Chenopodium album. However, both the population parameters (R(0), r, λ, and T) and the population prediction results suggest that L. sticticalis can adapt to P. sativam and V. sativa. In the process of promoting green manure, careful consideration should be given to the selection of appropriate green manure varieties and the implementation of effective pest control measures during their planting. Our findings lay the groundwork for the promotion of green manure and implementation of an ecological management plan for L. sticticalis.