Effects of cold storage on the quality of<i>Trichogramma dendrolimi</i>Matsumura (Hymenoptera: Trichogrammatidae) reared on artificial medium

Cold storage and heat exposure are crucial components of tephritid fruit fly mass-rearing programs, as they influence the development and fitness traits of produced flies. This work investigated the effects of cold storage on the pupal developmental parameters and quality of Bactrocera dorsalis (Hendel) genetic sexing strain (GSS) adults. Furthermore, the impact of short-term thermal exposure on the fecundity of B. dorsalis (GSS) that also underwent pupal cold storage was examined. Our results show that pupal development time, emergence rate, partial emergence rate, flight ability and fecundity were significantly affected by low temperature and pupal age and their interaction. Pupal cold storage did not pose negative impacts on the mating competition and response to methyl eugenol (ME) in the males. In addition, compared with the adults that were subjected to the same pupal storage protocol (five-day-old pupae stored at 13 °C), adult exposure to 41 °C for 1 h showed significant reparative effects on fecundity. In summary, the cold storage procedure of B. dorsalis (GSS) pupae has the potential to improve the flexibility and efficiency of mass-rearing schedules. Furthermore, short-term thermal exposure showed reparative effects on the fecundity costs induced by pupal cold storage in B. dorsalis (GSS).

Section: Discussionsupporting

confidence: 86%

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

Lin

Yamada

et al. 2020

“…However, keeping parasitoids at a sub-ambient temperature can result in cold injuries and excessive consumption of energy reserves, resulting in undesirable effects on the quality and quantity of post-storage parasitoids [ 11 ]. Hence, to minimize losses in the performance of parasitoids after undergoing storage, packaging, and shipment, recent research has focused on optimizing the tradeoffs between quality and the cold storage protocol [ 12 , 13 , 14 ]. For braconid parasitoids against tephritid pests, the impacts of cold storage have been evaluated in several species, such as Psyttalia humilis (Silvestri), Psyttalia ponerophaga (Silvestri), Fopius arisanus (Sonan), and Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae); these works have provided a lot of valuable information for facilitating the practical application of biological control programs [ 15 , 16 , 17 ].…”

Section: Introductionmentioning

confidence: 99%

Effect of Cold Storage on the Quality of Psyttalia incisi (Hymenoptera: Braconidae), a Larval Parasitoid of Bactrocera dorsalis (Diptera: Tephritidae)

Lin

Yang

Hao

et al. 2021

Psyttalia incisi (Silvestri) is the dominant parasitoid against Bactrocera dorsalis (Hendel) in fruit-producing regions of southern China. Prior to a large-scale release, it is important to generate a sufficient stockpile of P. incisi whilst considering how best to maintain their quality and performance; cold storage is an ideal method to achieve these aims. In this study, the impacts of temperature and storage duration on the developmental parameters of P. incisi pupae at different age intervals were assessed. Then, four of the cold storage protocols were chosen for further evaluating their impacts on the quality parameters of post-storage adults. Results showed that the emergence rate of P. incisi was significantly affected by storage temperature, storage duration, and pupal age interval and their interactions. However, when late-age P. incisi pupae developed at a temperature of 13 °C for 10 or 15 d, no undesirable impacts on dry weight, flight ability, longevity, reproduction parameters of post-storage adults, emergence rate, or the female proportion of progeny were recorded. Our findings demonstrate that cold storage has the potential for enhancing the flexibility and effectiveness of the large-scale production and application of P. incisi.

“…Biochemical characteristics, including trehalose content and trehalase activity in T. dendrolimi, continuously reared on artificial medium (in vitro) versus those reared on A. pernyi eggs (in vivo), were also studied [11]. The quality of in vitro reared T. dendrolimi was strongly affected by cold storage, but prepupae could be successfully stored at 13 • C for up to 4 weeks [12].…”

Section: Introductionmentioning

confidence: 99%

“…Trichogramma spp. show different reactions to low temperatures when reared on different hosts or media [12,13]. For T. dendrolimi, the developmental threshold temperature was different among geographical populations and hosts: 10.34 • C for south population reared on Philosamia cynthia ricini [13]; 10.1 • C for the south population reared on C. cephalonica [14]; 5.34 • C/5.1 • C, 5.82 • C/5.42 • C, 11.03 • C/14.83 • C, and 12.37 • C/11.58 • C for the north population (egg, larva, prepupa and pupa) reared on A. pernyi [15,16].…”

Section: Introductionmentioning

confidence: 99%

Gene Characterization and Enzymatic Activities Related to Trehalose Metabolism of In Vitro Reared Trichogramma dendrolimi Matsumura (Hymenoptera: Trichogrammatidae) under Sustained Cold Stress

Lü,

Han,

et al. 2020

Self Cite

Trichogramma spp. is an important egg parasitoid wasp for biocontrol of agriculture and forestry insect pests. Trehalose serves as an energy source or stress protectant for insects. To study the potential role of trehalose in cold resistance on an egg parasitoid, cDNA for trehalose-6-phosphate synthase (TPS) and soluble trehalase (TRE) from Trichogramma dendrolimi were cloned and characterized. Gene expressions and enzyme activities of TdTPS and TdTRE were determined in larvae, prepupae, pupae, and adults at sustained low temperatures, 13 °C and 16 °C. TdTPS and TdTRE expressions had similar patterns with higher levels in prepupae at 13 °C and 16 °C. TdTPS enzyme activities increased with a decrease of temperature, and TdTRE activity in prepupae decreased sharply at these two low temperatures. In vitro reared T. dendrolimi could complete entire development above 13 °C, and the development period was prolonged without cold injury. Results indicated trehalose might regulate growth and the metabolic process of cold tolerance. Moreover, 13 °C is the cold tolerance threshold temperature and the prepupal stage is a critical developmental period for in vitro reared T. dendrolimi. These findings identify a low cost, prolonged development rearing method, and the cold tolerance for T. dendrolimi, which will facilitate improved mass rearing methods for biocontrol.