Effects of predation risks of bats on the growth, development, reproduction, and hormone levels of Spodoptera litura

Abstract

Predation is a powerful selection pressure that shapes predator–prey interactions. Due to long-term interactions, moths have developed hearing to detect the echolocation calls of bats. This allows bats to impose the non-consumptive effects of predation on moths. However, information on the changes in the growth, development, reproduction, and hormones of moths that are vulnerable to bat predation is limited. In this study, we used Spodoptera litura (Lepidoptera: Noctuidae) to determine the effects of the predation risks of bats on their growth, development, reproduction, and hormone titers. Our results showed that the larvae of S. litura increased food intake, accelerated the development of the larval stages, increased mortality and metamorphosis failure, and had a smaller body size under the risk of predation by bats. Additionally, the reproductive activity and fecundity decreased in the adults of S. litura, but the juvenile hormone titers and 20-Ecdydysone hormone titers increased. These results suggested an adaptive response in S. litura under bat predation risks at the cost of lower survival and reproduction. Finally, we found that S. litura moths showed different responses to different predation risk cues, which suggested that they might assess the magnitude of different predation risks to make the most suitable decision for survival and reproduction. Our results highlight the importance of the predation risk imposed by bats to negatively regulate the population dynamics of moths. Our findings indicated that the biological control of bugs using bats is a promising strategy.

Non-Consumptive Effects of Harmonia axyridis on the Reproduction and Metabolism of Spodoptera frugiperda

“…Additionally, exposure to cadmium changed the larval body size and weight of D. melanogaster , prolonged the pupation and eclosion time, and disrupted the level of JH and 20E [ 38 ]. Meanwhile, Spodoptera litura (Lepidoptera: Noctuidae) exposed to non-consumptive effects showed elevated levels of JH and 20E to varying extents, and the increase in the JH titers enhanced the reproductive activities of adults, while the increase in 20E titers promoted the immune activities of adults [ 39 ]. Vitellogenin synthesis is fundamental for vitellogenesis, egg maturation, and embryonic development, directly impacting insects’ fertility, and vitellogenin also plays non-nutritional roles by functioning as immune-relevant molecules and antioxidant reagents [ 40 ].…”

“…An increase in immune function could lead to a decrease in reproductive activity due to the allocation of lesser energy to reproduction, and conversely, infection and activation of the immune system could reduce reproductive output [ 61 ]. There was a tradeoff between reproduction and immunity in S. litura when exposed to non-consumptive effects, and energy was preferentially allocated to immunity, resulting in decreased reproductive activity and fecundity [ 39 ]. In our study, non-consumptive effects led to increased antioxidant enzyme activity, heightened carbohydrate consumption, and decreased fecundity.…”

Don’t Leave the Past Behind: How Larval Experience Shapes Pupal Antipredator Response inAedes aegypti

“…risk in complex life cycles(McCauley et al, 2011;Pechenik, 2006;Roux et al, 2021;Zhang et al, 2023). We highlight the importance of early predation experience in shaping the evolution of behavioural traits in a complex life cycle with extreme metamorphosis.…”