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Simple Summary: Trichogramma chilonis is widely used for biological control, but there is a lack of efficient and available host eggs for the production of this parasitoid. Samia cynthia ricini, an economically valuable, non-mulberry silkworm, was previously reported to be used for the reproduction of Trichogramma spp. but subsequently received less attention, and more details about its use are unknown. Through laboratory experiments, we found that the suitable developmental temperature for adult S. c. ricini is 25–28 °C, and the adults must undergo at least 24 h of development time after emergence to lay more qualified eggs. T. chilonis has a type II functional response to S. c. ricini eggs. In brief, this means that as S. c. ricini egg density increases, the number of eggs parasitized by T. chilonis will gradually increase, but the growth rate will slow down and eventually reach a saturation state. Accordingly, by coordinating the ratio of parasitoid wasps to host eggs, we found that S. c. ricini eggs demonstrated excellent reproductive efficiency in terms of the reproduction of T. chilonis when the ratios were 1:2 and 1:3. We concluded that S. c. ricini eggs are potentially an excellent host egg for breeding T. chilonis and should be given more attention. T. chilonis is a commonly used biological agent, but its existing host eggs have shown some problems in the breeding of T. chilonis, and the search for more suitable host eggs is imminent. Here, we focused on S. c. ricini, an intermediate host that was used in the past for Trichogramma 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 T. chilonis to S. c. ricini egg, and screened for a suitable wasp-to-egg ratio for the production of T. chilonis. Our results showed that the developmental temperature and duration after the emergence of T. chilonis significantly affected adult longevity and oviposition, that 25–28 °C is a suitable temperature range for the survival and e-g laying of S. c. ricini, and that a developmental duration of at least 24 h was required to obtain more qualified S. c. ricini eggs. T. chilonis demonstrated a type II functional response to S. c. ricini eggs; different wasp-to-egg ratios significantly affected the propagation efficiency of T. chilonis reproduction from S. c. ricini 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 T. chilonis. [ABSTRACT FROM AUTHOR]

T. chilonis is a commonly used biological agent, but its existing host eggs have shown some problems in the breeding of T. chilonis, and the search for more suitable host eggs is imminent. Here, we focused on S. c. ricini, an intermediate host that was used in the past for Trichogramma 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 T. chilonis to S. c. ricini egg, and screened for a suitable wasp-to-egg ratio for the production of T. chilonis. Our results showed that the developmental temperature and duration after the emergence of T. chilonis significantly affected adult longevity and oviposition, that 25–28 °C is a suitable temperature range for the survival and e-g laying of S. c. ricini, and that a developmental duration of at least 24 h was required to obtain more qualified S. c. ricini eggs. T. chilonis demonstrated a type II functional response to S. c. ricini eggs; different wasp-to-egg ratios significantly affected the propagation efficiency of T. chilonis reproduction from S. c. ricini 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 T. chilonis.

Abstract Background Lycoris species have great ornamental and medicinal values; however, their low regeneration efficiency seriously restricts their commercial production. Understanding the mechanism of bulblet propagation in this genus, which has remained underexplored to date, could provide a theoretical basis for improving the reproductive efficiency. Therefore, we studied the bulblet initiation and developmental processes in Lycoris radiata. Results We found that bulblets are formed on the junctions of the innermost layers of scales and the basal plate, and initially present as an axillary bud and gradually develop into a bulblet. We also determined the changes in carbohydrate and endogenous hormone contents during bulblet initiation and development, as well as the expression patterns of genes involved in carbohydrate metabolism and hormone biosynthesis and signaling through transcriptome analysis. Soluble sugars derived from starch degradation in the outer scales are transported to and promote bulblet initiation and development through starch synthesis in the inner scales. This process is mediated by several genes involved in carbohydrate metabolism, especially genes encoding ADP glucose pyrophosphorylase, a crucial starch synthesis enzyme. As for hormones, endogenous IAA, GA, and ABA content showed an increase and decrease during bulblet initiation and development, respectively, which were consistent with the expression patterns of genes involved in IAA, GA, and ABA synthesis and signal transduction. In addition, a decrease in ZR content may be down- and up-regulated by CK biosynthesis and degradation related genes, respectively, with increasing auxin content. Furthermore, expression levels of genes related to BR, JA, and SA biosynthesis were increased, while that of ethylene biosynthesis genes was decreased, which was also consistent with the expression patterns of their signal transduction genes. Conclusions The present study provides insights into the effect of carbohydrate metabolism and endogenous hormone regulation on control of L. radiata bulblet initiation and development. Based on the results, we propose several suggestions to improve L. radiata propagation efficiency in production, which will provide directions for future research.

Background: Lycoris species have great ornamental and medicinal values; however, their low regeneration efficiency seriously restricts their commercial production. Understanding the mechanism of bulblet propagation in this genus, which has remained underexplored to date, could provide a theoretical basis for improving the reproductive efficiency. Therefore, we studied the bulblet initiation and developmental processes in Lycoris radiata. Results: We found that bulblets are formed on the junctions of the innermost layers of scales and the basal plate, and initially present as an axillary bud and gradually develop into a bulblet. We also determined the changes in carbohydrate and endogenous hormone contents during bulblet initiation and development, as well as the expression patterns of genes involved in carbohydrate metabolism and hormone biosynthesis and signaling through transcriptome analysis. Soluble sugars derived from starch degradation in the outer scales are transported to and promote bulblet initiation and development through starch synthesis in the inner scales. This process is mediated by several genes involved in carbohydrate metabolism, especially genes encoding ADP glucose pyrophosphorylase, a crucial starch synthesis enzyme. As for hormones, endogenous IAA, GA, and ABA content showed an increase and decrease during bulblet initiation and development, respectively, which were consistent with the expression patterns of genes involved in IAA, GA, and ABA synthesis and signal transduction. In addition, a decrease in ZR content may be down- and up-regulated by CK biosynthesis and degradation related genes, respectively, with increasing auxin content. Furthermore, expression levels of genes related to BR, JA, and SA biosynthesis were increased, while that of ethylene biosynthesis genes was decreased, which was also consistent with the expression patterns of their signal transduction genes. Conclusions: The present study provides insights into the effect of carbohydrate metabolism and endogenous hormone regulation on control of L. radiata bulblet initiation and development. Based on the results, we propose several suggestions to improve L. radiata propagation efficiency in production, which will provide directions for future research. [ABSTRACT FROM AUTHOR]

Taking the atmospheric refraction, extinction and turbulence into account, the propagation characteristic of supercontinuum laser sources in a slant path through the turbulent atmosphere is investigated. The effect of spectral width, initial spot size and zenith angle in a slant path on the beam width and propagation efficiency are studied in details. Numerical examples reveal that the beam width and propagation efficiency are different values while the spectral width varies. With the zenith angle in a slant atmospheric path increasing, the beam width of supercontinuum laser sources will increase and propagation efficiency will decrease. The initial spot size has an optimal value when spectral width and zenith angle are fixed. [ABSTRACT FROM AUTHOR]