A method for in-situ assessment of soybean suitability to Clanis bilineata tsingtauica Mell and selecting for rearing specialized varieties

Clanis bilineata tsingtauica Mell (CBT) is a traditional edible insect. This study aimed to (1) establish an in-situ procedure for determining the suitability of soybean varieties for CBT rearing and (2) identify soybean varieties that are most conducive to CBT rearing. We developed two isolation rearing methods: the first employs mesh bags as isolation rearing tools in net houses (BIRN) and fields (BIRF), and the second uses net houses directly as isolation rearing tools (IRN). The suitability of fourteen soybean varieties with different maturity groups to CBT was assessed. Based on F values and genetic variation coefficients from single-factor and combined variance analyses across various environments, the weight of 15-day-old larvae was identified as the primary suitability indicator for BIRN and BIRF, and the 25-day-old larvae weight per plot was selected as the key indicator for IRN. BIRN and BIRF methods offer advantages such as moderate cost and high throughput, completing evaluations in just one-sixths of the consumable expenses required by IFN. IRN method more accurately reflects actual production condition, with larvae reared on mid-late maturing, lodging-resistant soybean varieties achieving significantly higher larval weights than those reared on other types of soybean varieties. BIRN and BIRF methods evaluate soybean varieties suitability for CBT primarily based on larval weight, whereas IRN considers both larval weight and larval survival rate. Thus, IRN provides a comprehensive assessment of soybean varieties suitability for CBT. BIRN and BIRF allow for multiple evaluations annually with low consumable expenses, while IRN can be employed to select varieties based on initial screening results from BIRN and BIRF. The combination of mesh bag and net house isolation rearing methods facilitates the identification of specialized soybean varieties for CBT rearing. By integrating both methods, two soybean varieties, NN18-25 and NN1138-2, were specifically identified optimal for CBT larval rearing.