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Simple Summary: Arma chinensis Fallou is a predaceous stink bug that can effectively control many kinds of agricultural and forest pests, such as fall armyworm, cotton bollworm and Colorado potato beetle. An insect-free artificial diet comprising chicken egg, tuna fish and raw pig liver was developed for A. chinensis. Several biological characteristics were diminished for A. chinensis reared on the artificial diet compared to the pupae of Chinese oak silk moth. Changes in the formulation of the diet were made in response to the transcriptome results and tested using biological characteristics. Several parameters were improved over 6 generations, although the improved artificial diet remained inferior to the pupae of Chinese oak silk moth regarding egg viability, fecundity, body weight, and nymphal development time. The current study reported the differential proteomic analysis revealing the mechanism of A. chinensis responding to the improved artificial diet. This information will be used to optimize the formulation of the artificial diet and decrease the cost of mass rearing in A. chinensis. The development of artificial diets could considerably simplify and reduce the cost of mass rearing of natural enemies compared to conventional rearing methods. However, improvement of artificial diets can be tedious, convoluted and often uncertain. For accelerating diet development, a better method that can offer informative feedback to target deficiencies in diet improvement is required. Our previous research demonstrated several biological characteristics were diminished in the insect predator, Arma chinensis Fallou, fed on an artificial diet formulated with the aid of transcriptomic methods compared to the Chinese oak silk moth pupae. The present study reports differential proteomic analysis by iTRAQ-PRM, which unravels the molecular mechanism of A. chinensis responding to improvements in the artificial diet. Our study provides multivariate proteomic data and provides comprehensive sequence information in studying A. chinensis. Further, the physiological roles of the differentially expressed proteins and pathways enable us to explain several biological differences between natural prey-fed and improved diet-fed A. chinensis, and subsequent proposed reformulation optimizations to artificial diets. [ABSTRACT FROM AUTHOR]

Telenomus remus (Nixon) has shown promising potential as a biological control agent for the major invasive agricultural pest, Spodoptera frugiperda (J. E. Smith). Application of biological control programmes in the field requires an efficient mass‐rearing system to provide sufficient numbers of beneficial insects. The short longevity of parasitoid adults and limited period of availability of host eggs are two factors affecting the mass‐rearing efficiency of T. remus. Using Spodoptera litura (Fabricius) eggs as an alternative host, the effects of cold storage of S. litura eggs and T. remus adults at 5°C, 8°C and 11°C for different time durations on the fitness of the parasitoid were investigated to identify the most suitable storage conditions. Results showed that T. remus can successfully exploit stored S. litura eggs, but the number of parasitized eggs decreased with increased egg storage duration and/or reduced storage temperature. For refrigerated adults, the survival rate declined gradually with longer storage duration, and the females' survival rate was higher than the males' at any treatment. Similarly, parasitism capacity of stored adults declined significantly with prolonged storage. Female adult longevity was significantly shorter than the control for all treatments. However, the offspring emergence rate and percentage of females were barely affected by cold storage. In conclusion, S. litura eggs can be stored at 11°C for up to 9 days and adult T. remus can be stored at 8°C or 11°C for up to 7 days without significant losses. Data obtained from this study will help coordinate different aspects of T. remus production, decreasing costs and improving the biocontrol materials' availability. [ABSTRACT FROM AUTHOR]

Simple Summary: Telenomus remus (Nixon) is a promising natural enemy of Spodoptera frugiperda (J. E. Smith). Successful implementation of a biocontrol program requires a mature rearing system to produce millions of beneficial insect products at lower costs. This parasitoid is successfully reared on Corcyra cephalonica (Stainton) eggs in several countries, however that host species is unsuitable for Chinese strains of T. remus. Fewer studies have been done using Spodoptera litura (Fabricius) eggs, but it is increasingly seen as the promising alternative host in China. In order to identify optimal mass-rearing conditions when using S. litura eggs as an alternative host, this novel study thus sought to comprehensively evaluate the effects of photoperiod, exposure time, and host egg:parasitoid ratio on the reproductive potential and mass-rearing efficiency of T. remus on S. litura eggs. Our results suggest using more than 12 h of light, 24 h exposure time, and 14–20:1 host egg:parasitoid ratio for rearing T. remus on S. litura eggs. These findings will help promote successful, large-scale rearing of T. remus for use against S. frugiperda in China. Telenomus remus (Nixon) is a dominant egg parasitoid of the destructive agricultural pest Spodoptera frugiperda (J. E. Smith), and so is used in augmentative biocontrol programs in several countries. An optimized mass-rearing system is essential to produce biological control products in a timely and cost-effective manner. In this study, the photoperiod, host egg:parasitoid ratio, and exposure time were evaluated to identify the optimal rearing conditions for T. remus on the alternative host Spodoptera litura (Fabricius) eggs. Results showed that increasing photoperiod above 12L:12D remarkably improved parasitoid progeny yield and life table parameters. Overlong photoperiods shortened female longevity, but within acceptable limits. There was a significant negative correlation between parasitism rate and host egg:parasitoid ratio under exposure times of 12 and 36 h, but not 24 h. Percentage of female progeny increased significantly along with increasing the host egg:parasitoid ratio. A significant negative relationship between the number of emerged adults per egg and the host egg:parasitoid ratio was observed at an exposure time of 36 h. It was concluded that T. remus may be mass-reared most efficiently on S. litura eggs using a photoperiod of more than 12L:12D, a 14–20:1 host egg:parasitoid ratio, and an exposure time of 24 h. These findings can be used to produce T. remus more efficiently and at lower costs. [ABSTRACT FROM AUTHOR]

Simple Summary: Telenomus remus (Nixon) is an effective egg parasitoid for controlling Spodoptera frugiperda (J. E. Smith), which is a major destructive agricultural pest. Currently, this parasitoid is reared on Corcyra cephalonica (Stainton) eggs in several countries. However, previous studies carried out in China have reported that it cannot parasitize in C. cephalonica eggs. Meanwhile, those works have indicated that Spodoptera litura (Fabricius) can potentially be used as an alternative host. In order to evaluate this potential, our study compared the development and parasitism ability of T. remus on the eggs of S. frugiperda and S. litura at different temperatures in a laboratory. We found that S. litura eggs are more advantageous as an alternative host for the mass-rearing of parasitoid when compared with S. frugiperda eggs. Our results provide a more specific basis and reference for the large-scale production and low temperature storage of T. remus. Although Telenomus remus, a promising parasitoid of Spodoptera frugiperda, had been successfully reared on the eggs of Corcyra cephalonica in some countries, reports from China have argued that it is infeasible. Notably, studies from China have indicated that Spodoptera litura eggs could be a candidate host. Therefore, to further evaluate the potential of using S. litura eggs as hosts, we compared the development and parasitism of T. remus on the eggs of S. frugiperda and S. litura at temperatures between 20–32 °C. Our results showed that T. remus developed successfully on both host eggs at all of the tested temperatures, and the developmental duration and thermal requirements at each stage were similar between the two host species. The number of parasitized eggs was greater for S. litura than for S. frugiperda. Meanwhile, the emergence rate exceeded 86.6%, and it was significantly higher for S. litura than that for S. frugiperda, except at 29 °C. This study is the first time estimating the thermal requirements of T. remus at each stage. Moreover, we also recorded the morphological characteristics of T. remus at each stage. Our results demonstrate that S. litura eggs are more suitable than S. frugiperda eggs as an alternative host for the mass-rearing of T. remus in China. Understanding the thermal requirements and biological parameters contributes greatly to predicting the generation time and providing a reference for the mass-rearing and storage of the parasitoid. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Photoperiod, moderated by temperature, is the major factor governing prepupal diapause induction in Chrysopa formosa. • Third instar larvae are most sensitive to photoperiod. • Chilling at 5 °C for 60 days is sufficient for diapause termination. • Diapausing chrysopids can be stored up to 300 days at 5 °C. Abstract Knowledge of environmental regulation of diapause in the green lacewing Chrysopa formosa , an important polyphagous predator against various pests, is essential for understanding seasonal adaptations of insects and for increasing the shelf-life and shipment of chrysopids used in biological control programs. In the present study, we identified environmental factors responsible for induction and termination of diapause and cold tolerance in this chrysopid. C. formosa exhibits a facultative, prepupal diapause within its cocoon. The free-living third instar larva is the stage most sensitive to photoperiodic stimuli. Photoperiod is the major factor governing the induction of prepupal diapause, and temperature exerts a modulating effect. Photoperiodic response curves for C. formosa showed a typical long day response over a wide range of temperatures. Critical daylength for diapause induction was estimated to be 14.3 h at 20 °C, with a shift towards short daylengths at higher temperatures. The diapause response was maximal with a short daylength of 8L: 16D at 18 °C or 20 °C, and no diapause was induced under 16L: 8D at any temperature examined. Chilling temperature had a pronounced effect on the completion of diapause termination and post-diapause development. A chilling period of 60 days or more at 5 °C was sufficient to terminate diapause in most prepupae. An increase of chilling exposure duration synchronized post-diapause development and adult emergence. What was particularly attractive is that diapausing chrysopids could be stored at 5 °C as long as 300 days with high survival and short adult emergence time. The developmental period prior to diapause was extended significantly for diapause-destined chrysopids. Prepupal diapause in C. formosa distinctly enhanced the cold tolerance. These results suggest mechanisms that could be exploited to improve shelf-life and long distance shipment of chrysopids for release in biological control program. [ABSTRACT FROM AUTHOR]