Research on the Reproduction of Trichogramma chilonis Based on Samia cynthia ricini Eggs: Temperature, Functional Response and Proportional Effect

<i>T. chilonis</i> is a commonly used biological agent, but its existing host eggs have shown some problems in the breeding of <i>T. chilonis</i>, and the search for more suitable host eggs is imminent. Here, we focused on <i>S. c. ricini</i>, an intermediate host that was used in the past for <i>Trichogramma</i> spp. but has since received less attention. We attempted to understand the effects of developmental temperature and duration on its longevity and egg production, evaluated the functional response of <i>T. chilonis</i> to <i>S. c. ricini</i> egg, and screened for a suitable wasp-to-egg ratio for the production of <i>T. chilonis</i>. Our results showed that the developmental temperature and duration after the emergence of <i>T. chilonis</i> significantly affected adult longevity and oviposition, that 25-28 °C is a suitable temperature range for the survival and e-g laying of <i>S. c. ricini</i>, and that a developmental duration of at least 24 h was required to obtain more qualified <i>S. c. ricini</i> eggs. <i>T. chilonis</i> demonstrated a type II functional response to <i>S. c. ricini</i> eggs; different wasp-to-egg ratios significantly affected the propagation efficiency of <i>T. chilonis</i> reproduction from <i>S. c. ricini</i> eggs, and the best reproduction efficiency was achieved with wasp-to-egg ratios of 1:2 and 1:3, Considering that there were no significant differences in most parameters between the two treatments, as well as cost concerns, we concluded that wasp-to-egg ratios of 1:2 are an important parameter that could be applied. Our results may provide some valuable insights into the mass rearing of <i>T. chilonis</i>.