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Antheraea pernyi Guerin-Meneville eggs have become an important host for rearing Trichogramma and are the preferred host for mass production of Trichogramma dendrolimi Mausumura, a widely used natural enemy in pest control practices. However, the effects of fertilization of host eggs on their mass production remains unclear. In this study, we evaluated parasitism and biological parameters for T. dendrolimi reared on A. pernyi eggs with five different treatments under the laboratory conditions. The five treatments were manually-extracted unfertilized washed eggs (MUW), naturally-laid unfertilized washed eggs (NUW) and unwashed (NUUW) eggs, naturally-laid fertilized washed eggs (NFW) and unwashed (NFUW) eggs. Our results showed that T. dendrolimi preferred MUW eggs to other treatments, although all treated A. pernyi eggs were accepted by T. dendrolimi . Generally, T. dendrolimi parasitized more washed eggs than unwashed eggs, and a greater number of unfertilized than fertilized eggs. On MUW eggs, the highest number of adults emerged per egg coupled with the shortest pre-emergence time and longest longevity of offspring. Those T. dendrolimi adults emerging from unfertilized eggs exhibited a higher number per egg, shorter pre-emergence time and longer adult longevity than those from fertilized eggs. There was no significant difference in percentage of female progeny, time to adult death, hind tibia length and egg load across all treatments. Our results demonstrate that MUW eggs of A. pernyi are most suitable for mass production of T. dendrolimi .

The life table is a type of research tool that is frequently used in many studies involving population and community ecology. They are the basis for many comprehensive studies in pest management, pesticide resistance, predator-prey relationships, biological control, mass-rearing and harvesting of insects, plant resistance, etc. Because the morphology, physiology, survival, fecundity, and predation/consumption rate of most arthropods will vary significantly depending on their developmental stage and sex, precise description of stage differentiation and inclusion of both sexes are critical for attaining realistic and accurate life table analyses and correctly evaluating the overall fitness of populations. Since traditional female age-specific life tables ignore the male individuals in a population and are incapable of describing the unique and important feature of stage differentiation (i.e., metamorphosis) that is a defining characteristic of insects and mites, their application to data analysis involving these groups will inevitably result in miscalculations and limit the practical application of these life tables. On the other hand, the age-stage, two-sex life table (hereafter referred to as the two-sex life table whenever appropriate), can precisely delineate stage differentiation and includes both sexes in data analysis, description, and interpretation, and in practical applications. In this review, the problems of female age-specific life tables are examined, followed by a discussion of the advantages of using the two-sex life table. Finally, applications of the two-sex life table in various types of entomological research are discussed and accompanied by examples.