Effects of Non-Lethal High-Temperature Stress on Bradysia odoriphaga (Diptera: Sciaridae) Larval Development and Offspring

Abstract

Throughout China, the dipteran pest Bradysia odoriphaga significantly reduces Chinese chive production; therefore, identifying conditions that influence its growth and development is crucial for developing ecological regulation strategies. In this study, different non-lethal high temperatures and treatment durations were used to stress the third-instar larvae of B. odoriphaga, and the effects of this treatment on their growth and offspring were recorded and analyzed. The results showed that the average larval mortality increased with increased temperature and prolonged exposure times. After stress treatment at 40 °C for 2 h, 100% of larvae died within 5 days, which was not significantly different from the 5-day average larval mortality (90.66%) after stress at 37 °C for 4 h, but significantly higher than the 5-day average larval mortality (72.00%) after stress at 40 °C for 1 h. After 5 days, all still-living larvae could pupate, and there was no significant difference in average pupal period after pupation. However, the eclosion rate of subsequent pupae decreased with increased temperature and prolonged exposure times, and were only 43.00% and 42.73% after larvae were stressed at 37 °C for 4 h and 40 °C for 1 h, respectively. After eclosion into adults, there was no significant difference in the lifespan of unmated female adults, while the lifespan of unmated male adults was significantly reduced to 1.67 d and 2 d after larvae were stressed at 37 °C for 4 h and 40 °C for 1 h, respectively. However, there was no significant difference in male and female adult longevity after mating. There was no significant difference in oviposition or egg hatchability. This indicates that non-lethal high temperature at 37 °C for 4 h can hinder development and allow control of B. odoriphaga. There is great potential for non-lethal high temperature to be applied in the field to control agricultural pests.

The Impact of High-Temperature Stress on the Growth and Development of Tuta absoluta (Meyrick)

“…This study demonstrates that the rate of pupal emergence gradually decreased as temperature and treatment time increased after pupal-stage exposure to high temperature. A significant reduction in emergence rate was observed after pupal-stage exposure to 44 °C for 6 h, which is consistent with a similar study [ 35 ]. The pupae of Grapholita molesta were exposed to high temperatures, which increased their longevity and reduced fecundity [ 36 ].…”

Effects of periodically repeated high‐temperature exposure on the immediate and subsequent fitness of different developmental stages ofPropylaea japonica

“…13 However, once the temperature exceeds their tolerance limits, it will lead to short (e.g., decreased survival rate or immediate death) and long-term adverse effects (i.e., potential carry-over effects on subsequent development stages and fecundity). [14][15][16][17] Most insect species suffer from temperature fluctuations in their dwelling environment throughout their ontogeny, which affects physiological processes and ecological functions. It is known that different developmental stages of insects have different thermal sensitivities, so high temperatures experienced in early ontogeny can affect biological characteristics and heat tolerance capacities in later development stages or the next generation.…”

“…In general, insects possess certain physiological self‐regulation functions in order to tolerate temperature changes 13 . However, once the temperature exceeds their tolerance limits, it will lead to short (e.g., decreased survival rate or immediate death) and long‐term adverse effects (i.e., potential carry‐over effects on subsequent development stages and fecundity) 14–17 …”

Effects of four constant temperatures on the development of two Bradysia (Diptera: Sciaridae) species

“…The responses of B. odoriphaga and B. impatiens to high temperatures have been reported (Gou, Guo, Wang, et al, 2020;Zhu et al, 2018). But previous studies focused mostly on lethal and sublethal short-term heat shocks and lacked the whole generation observations under constant high temperature exposure (Luo et al, 2017;Shi et al, 2020;Zhu et al, 2017Zhu et al, , 2018. Cheng et al reported negative effects of high temperatures (31, 33, 35 and 37°C) and exposure times (from 0 min to 120 min) on the survival, fecundity and offspring development of B. odoriphaga (Cheng et al, 2017).…”