Age-Stage, Two-Sex Life Tables of (Bagnall) and (Trybom) on Different Bean Pods Under Laboratory Conditions: Implications for Their Competitive Interactions.

As two major pests of cowpea in South China, bean flower thrips [ (Bagnall)] and flower thrips [ (Trybom)] always occur on the same plant. In this study, the two-sex life table parameters of these two species were investigated on three bean pods: cowpea ( L. var. Chunqiu Wujiadou), snap bean ( L. var. Yonglong 3), and green bean ( L. var. Linghangzhe) using standard cut bean protocols. Longevity of female adult showed no significant difference on cowpea and snap bean, but was shortest on green bean, with the highest fecundity on snap bean, followed by cowpea and green bean. Longevity and fecundity of female adult were both highest on cowpea, followed by snap bean and green bean. On snap bean, the population parameters (, , ) of were higher than , whereas and were not different, suggesting that were more competitive on snap bean. On cowpea, the population parameters (, , , ) of were higher than . , suggesting a competitive advantage of on cowpea. To better mimic field conditions, we investigated the survival and fecundity of adult under two distinct scenarios: when they could feed directly on cut surfaces of cowpeas (standard lab protocol), and when they could not. Adult survival of is not significantly influenced by whether or not they fed directly on cut surfaces of cowpeas. However, a notable decrease in fecundity was observed in that fed on surface-covered cut pods. This suggested that direct feeding on cut surfaces of cowpea did have an impact on thrips' fecundity, offering fresh perspectives for future research into the growth and development of thrips in a laboratory. Our study suggests that experiments involving cut surfaces may be misleading, and further investigations are ongoing to address these concerns.