Artificially selected starvation-resistant lines of Pachycrepoideus vindemmiae with multiple beneficial traits: Shedding new light on stress resistance mechanisms and biological control applications of natural enemies

Abstract

Artificial selection for stress resistance in natural enemies is a promising approach to enhance their effectiveness in biological control. However, documented cases regarding artificial selection for starvation resistance in natural enemy insects are lacking. This study addresses this gap by selecting starvation-resistant lines of the parasitoid wasp Pachycrepoideus vindemmiae, including food deprivation resistance lines and food and water deprivation resistance lines. Our results demonstrate that all selected lines exhibited significantly improved survival abilities compared to non-selected lines. Moreover, resistance to starvation persisted across generations without artificial selection under starvation conditions, indicating stable inheritance of this trait. We also observed extended lifespan in female adults and enhanced resistance to desiccation and low temperature in both males and females from the resistance lines. Additionally, we conducted preliminary exploration of the mechanisms underlying starvation resistance in these resistant lines through transcriptome sequencing for the first time. The analysis revealed that, under starvation stress, pathways such as amino acid metabolism and nucleotide metabolism exhibited consistent expression patterns in both resistant and non-resistant lines. However, specific pathways including arachidonic acid metabolism in lipid metabolism, and glyoxylate and dicarboxylate metabolism as well as glycolysis/gluconeogenesis in carbohydrate metabolism, were upregulated only in the resistant lines. These findings suggest that starvation resistance in the resistance lines involves multiple molecular pathways. This study represents the first successful artificial selection for starvation-resistant natural enemy lines, offering valuable insights for utilizing natural enemies effectively and understanding stress resistance mechanisms for potential genetic modification of beneficial traits.