Effects of cold storage on quality of Chrysopa pallens and recovery of fecundity by insulin

Abstract

The green lacewing, Chrysopa pallens Wesmael, is one of the most beneficial and prolific insects found in many horticultural and agricultural cropping system. Here, the effects of low temperature storage on quality of C. pallens were investigated by storing cocoons at 10 °C for different days. Results revealed, after removal from cold storage, emergence rate declined gradually as storage duration increased. After storage of 20 days, the emergence rate in cold-stored group is about 62.8% of that in unstored group. After eclosion, lifetime fecundity, preemergence period, oviposition period and longevity of adults in cold-stored group showed curves similar to emergence rate. However, preoviposition period and egg hatchability were not significantly affected by cold. After being stored for 20 days, the total fecundity of females emerging from cold-stored cocoons was about 64.5% of that of females emerging from unstored cocoons. Six days post emergence, females in cold-stored group showed apparent arrest of ovarian development and significant reductions of protease, lipase and trehalase activities when compared to unstored controls. When bovine insulin was exogenously used, the females emerging from cold-stored cocoons dramatically restored ovarian development and reproductive capacity. These results suggested that C. pallens pupae are suitable for cold storage and insulin hormone can be used as reproduction stimuli in this predatory species after cold storage.

Predatory Capacity and Reproduction of Cyrtorhinus lividipennis (Hemiptera: Miridae) Adults Exposed to Low-Temperature Storage and Fitness of the F1 Generation

“…Cold storage usually entails fitness costs in the exposed parental generation of IPM predators [ 11 , 23 , 24 , 25 ]. In this study, LTS did not influence the longevity of the post-storage C. lividipennis adults but significantly reduced the number of offspring nymphs per female by 55.6% in the post-storage females compared with the control females.…”

Quantification and Impact of Cold Storage and Heat Exposure on Mass Rearing Program of Bactrocera dorsalis (Diptera:Tephritidae) Genetic Sexing Strain

“…The reproductive organs of insects are particularly vulnerable to low temperature effects [ 47 ], and the cost of fecundity is usually proportional to the chilling temperature and storage time [ 24 , 48 ]. Our results indicate that storage temperatures below 16 °C imposed negative effects on the fecundity of B. dorsalis (GSS).…”

“…Although cold storage is regarded as a crucial procedure to improve the rearing efficiency in large-scale programs, the adverse impacts on fecundity induced by low temperatures severely threatens the applicability of this technique [ 24 ]. Thus, means by which these detrimental effects could be repaired or minimized need to be considered.…”

Effect of cold storage on development and demographic parameters ofScolothrips longicornisfed on two-spotted spider mite

“…We selected 5 °C since this temperature is above the lowtemperature threshold of 3.96 °C estimated by Pakyari et al (2011a). Another reason for selecting 5 °C was that several research studies have demonstrated that the appropriate temperature for storage of insect predators ranges from 1 to 10 °C (Abdel-Salam and Abdel-Baky, 2000; Sakaki et al, 2019;Zhang et al, 2019), and this provides a mid-point with which to assess effects on S. longicornis biological parameters This contribution describes research to establish the optimal temperature for storage of S. longicornis, with a view of developing recommendations for commercial rearing operations in biocontrol programs targeting T. urticae.…”

“…When mass rearing natural enemies for inundative releases, it is also essential to choose the life stage that can tolerate low-temperature storage (Benelli et al ., 2018). In this respect, the pupal and adult stages of predatory insects are considered to be the most appropriate stage for low-temperature storage (Abdel-Salam and Abdel-Baky, 2000; Zhang et al ., 2019).…”