Sycanus croceovittatus is an important natural enemy insect that can prey on a variety of Lepidoptera and Coleoptera pests, and has good potential for biocontrol development. In order to select suitable hosts for indoor mass rearing of S. croceovittatus, this study used age-stage, two-sex life table technology to investigate the developmental period, survival rate, fecundity, and population parameters under indoor conditions. The size of each state of S. croceovittatus feeding on Tenebrio molitor pupae was measured, the population dynamics were also predicted. The results showed that under the room temperature of 23℃ ± 2℃, the average developmental durations of S. croceovittatus eggs and 1^st to 5^th instars was 20.00 d, 14.75 d, 13.40 d, 11.67 d, 12.76 d and 21.25 d, respectively, and the average longevity of female and male adults was 54.75 d and 49.50 d, respectively. The intrinsic rate of increase r, finite rate of increase (λ), net reproductive rate (R₀) and mean generation period (T) was 0.039 d^-1, 1.040 d^-1, 115.361 eggs/female and 121.909 d, respectively. The body weights, lengths, and widths of the female adults were significantly higher than those of the male adults. Female adults could lay eggs whether they were mated or not, and reproductive parameters such as oviposition times, single fecundity and total fecundity of mated females were significantly higher than those of unmated female adults. The hatching rate of eggs laid by female adults after mating was 92.59%, while eggs laid by unmated female adults failed to hatch normally. The population of S. croceovittatus reared with T. molitor pupae shows positive growth and good individual development, indicating that T. molitor is feasible as an alternative prey for large scale breeding of S. croceovittatus.

To explore the composition of visiting flower arthropod communities and the activity rhythm of dominant species on different flowering plants in tobacco fields, we conducted a study using visual observation, sweep netting, and other survey methods to investigate the species composition and visiting characteristics of flower-visiting arthropods on six species of flowering plants in tobacco fields. The results showed that there were 44 flower-visiting arthropods from 34 families in 8 orders on Tagetes erecta, 50 species from 36 families in 9 orders on Vicia villosa, 53 species from 37 families in 7 orders on Fagopyrum esculentum, 55 species from 38 families in 8 orders on Lobularia maritima, 19 species from 17 families in 7 orders on Tifolium repense, and 54 species from 38 families in 8 orders on Argyranthemum frutescens. The dominant species were Frankliniella occidentalis, Apolygus lucorum, Orius similis, Sitobion miscanthi, Musca domestica, Eristalis arbustorum, Eurydema dominulus, Phyllotreta striolata, and Nysius thymi. The occurrence peak, activity rhythm, and behavioral characteristics of each dominant species on different flowering plants were distinct. The main predators, E. arbustorum and O. similis, were found to have the highest visitation proportions on L. maritima (13.52%) and T. erecta (12.35%) respectively. During the peak flowering period of T. erecta and L. maritima, there were visitation peaks of E. arbustorum and O. similis from 10:00 to 13:00 and 12:00 to 14:00 respectively, with the highest visitation frequencies of 2.56 and 1.49 individuals/min respectively. L. maritima and T. erecta had a strong attractive effect on natural enemies such as E. arbustorum and O. similis, not only attracting the most individuals, but also keeping them on the flowers for a longer time with the highest visitation frequency. This finding provides a theoretical basis for the biological control of major tobacco pests such as tobacco aphids and western flower thrips. In conclusion, planting plants such as L. maritima and T. erecta in the ecological system of tobacco fields can serve as excellent carriers for natural enemies. By planting these plants in tobacco fields, it is effective to increase the accumulation of natural enemies such as E. arbustorum and O. similis, thereby achieving the biological control of major tobacco pests such as tobacco aphids and western flower thrips.