The Potential Coordination of the Heat-Shock Proteins and Antioxidant Enzyme Genes of Aphidius gifuensis in Response to Thermal Stress

Abstract

Aphidius gifuensis is one of the most important aphid natural enemies and has been successfully used to control Myzys persicae and other aphid species. High temperature in summer is one of the key barriers for the application of A. gifuensis in the field and greenhouse. In this work, we investigated the biological performance of A. gifuensis and the response of heat-shock proteins and antioxidant enzymes under high temperature. The results showed that A. gifuensis could not survive at 40°C and female exhibited a higher survival in 35°C. Furthermore, the short term exposure to high temperature negatively affected the performance of A. gifuensis especially parasitism efficiency. Under short-term heating, the expression of AgifsHSP, Agifl(2)efl, AgifHSP70, AgifHSP70-4 and AgifHSP90 showed an increased trend, whereas AgifHSP10 initially increased and then decreased. In 35°C, the expressions of Agifl(2)efl, AgifHSP70-4 and AgifHSP90 in female were higher than those in male, whereas the expression of AgifHSP70 exhibited an opposite trend. Besides the HSPs, we also quantified the expression levels of 11 antioxidant enzyme genes: AgifPOD, AgifSOD1, AgifSOD2, AgifSOD3, AgifCAT1, AgifCAT2, AgifGST1, AgifGST2, AgifGST3, AgifGST4 and AgifGST5. We found that the sex-specific expression of AgifSOD2, AgifSOD3, AgifPOD, AgifGST1 and AgifGST3 were highly consistent with sex-specific heat shock survival rates at 35°C. Furthermore, when the temperature was above 30°C, the activities of GST, SOD, CAT and POD were significantly increased; however, there was no significant difference of the CAT activity between the male and female at 35°C. Collectively, all of these results suggested that the protection of thermal damage is coordinated by HSPs and antioxidant enzymes in A. gifuensis. Based on the heat tolerance abilities of many aphid natural enemies, we also discussed an integrated application strategy of many aphid enemies in summer.

Effect of short-term high-temperature exposure on the life history parameters of Ophraella communa

“…However, in a few studies, the female proportion increased with temperature, as was the case for the parasitoid Campoletis chlorideae 44 under controlled temperatures. Differential mortality between males and females in Trichogramma euproctidis 45 and Aphidius gifuensis 46 may be caused by developmental temperatures that result in a biased sex ratio, which might explain this phenomenon. The influence of extreme variations in temperature on sex ratio was reported by Werren and Charnov 47 , who predicted that there may be sex-biased mortality during a cold or heat wave.…”

Effect of Sublethal Doses of Imidacloprid on the Biological Performance of Aphid Endoparasitoid Aphidius gifuensis (Hymenoptera: Aphidiidae) and Influence on Its Related Gene Expression

“…At the time of exposure, twenty 2-day old A. gifuensis female adults were introduced into a vial. Twenty-four hours later, the mortality of A. gifuensis was counted and living parasitoids (at least 15) were individually collected to test the effects of IMD on the parasitism, longevity and sex ratio of offspring as described by Kang et al (2017a) with little modification. Chili pepper plant with 200 second- or third- instar M. persicae were placed into a plastic cage (diameter: 13 cm; height: 30 cm) with screen mesh caps.…”

“…The activities of CarE, SOD, CAT, POD, and GST were measured using commercially available assay kits (Nanjing Jiancheng Bioengineering Institute, Jiangsu, China) as described previously (Kang et al, 2017a).…”

“…Aphidius gifuensis Ashmead (Hymenoptera: Braconidae) is one of the most widely distributed and dominant endoparasitoid of pest aphids, including M. persicae and Sitobion avenae (Fabricius), and are successfully applied in greenhouses for controlling vegetable aphids and in fields for tobacco aphid ( M. persicae , also known as green peach aphid) management in China (Yang et al, 2009, 2011; Ali et al, 2016; Kang et al, 2017a; Yang F. et al, 2017). Furthermore, Yang et al (2009) reported that after augmentative releases of A. gifuensis , the frequency and quantity of pesticide application could be sustained at a low level for 8 years.…”

Volatile β-Ocimene Can Regulate Developmental Performance of Peach Aphid Myzus persicae Through Activation of Defense Responses in Chinese Cabbage Brassica pekinensis

“…In this study, we examined the interaction between Chinese cabbage and M. persicae to evaluate potential application of the plant volatile β-ocimene. We initially assessed the activation effect of β-ocimene on plant immune response and then analyzed the influence of β-ocimene on the orientation behavior of winged aphid and a parasitic wasp, Aphidius gifuensis , which is an endoparasitoid of M. persicae and has been used as a biological agent in the field and greenhouse ( Yang et al, 2011 ; Kang et al, 2017a ). Furthermore, we also investigated how M. persicae responds to the defense responses induced in its host plant.…”