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This paper reviews and introduces innovative research pertaining to the age-stage, two-sex life table. The main topics discussed are: (1) Analysis of data involving group-reared life table studies. We address the rationale behind the data analysis used when constructing a group-reared life table. Proper analysis of grouped-reared life table data enables the collection of realistic and applicable data for ecological studies, devising efficient mass-rearing programs and formulating pest management routines using time- and labor-saving group-rearing methods. (2) The bootstrap-match technique. This novel technique is applicable to those instances when constructing a complete life table involves collecting the immature independently from the adult data. (3) Application of the set theory in life table research. This procedure enables a mathematical description of the population structure and bootstrap samples. (4) Application of the multinomial theorem. Using the multinomial theorem enables calculation of the exact probability of bootstrap samples. (5) Inclusion of infertile bootstrap samples. Because it is impossible to calculate the intrinsic rates of increase for infertile samples, they are normally omitted in life table analysis. Inclusion of these infertile bootstrap samples produces an unbiased life table analysis. (6) The Cartesian product. The Cartesian product of two sets produces the complete coverage of all possible differences. We compared the paired bootstrap test, the Cartesian paired test based on bootstrap results, and the Cartesian paired test based on the multinomial theorem. (7) Integration of life table data with predation data. This procedure, which is especially relevant to biological control programs, enables a comprehensive study of the predator-prey relationship. (8) Computer simulation based on life tables. Population projection based on the age-stage, two-sex life table not only provides the means to predict the dynamics of stage structures of a given pest population, but also provides an insight into the dynamics of predation capacity of the predator population. (9) Problems in life table research. Each of the subjects discussed is crucial for the theoretical advancement and practical applications of scientific demographic research. [ABSTRACT FROM AUTHOR]

We developed an innovative bootstrap-match technique for use in life table construction. This technique should be considered when any of the following four situations occur: 1) It is necessary to collect the immature and adult life table data separately due to obligatory diapause of one of the life stages. 2) It is necessary to collect the immature and adult life table data separately due to the difficulties in mating the adults under controlled laboratory conditions. 3) A large cohort is used for collecting immature data but a much smaller cohort is used for the adult data. 4) The life table data for the immatures were collected using individually reared insects while the adult data was obtained using group-reared insects. In order to demonstrate the applicability and reliability of this technique, we split twelve life tables of various insect species from previously published papers into two distinct components as if they were collected separately and then reunited them using the bootstrap-match technique. The population parameters of the bootstrap-match life tables were all highly consistent with the original life tables. We applied this technique to the Sunn pest, Eurygaster integriceps Puton, which has one generation per year and goes through an extended dormancy period averaging ~300 days (includes aestivation and overwintering). We demonstrated that ignoring the overwinter duration will result in unrealistic overestimation of population parameters. Conversely, bootstrap-match life tables that included the overwintering duration generated more realistic population parameters. Population projections using bootstrap-match life tables were also shown to generate realistic predictions of the population growth. [ABSTRACT FROM AUTHOR]

Antheraea pernyi Guérin-Méneville 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), naturallylaid 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]