Energy Metabolism-Mediated Heat Acclimation Enhances Reproductive and Migratory Capacities of Cnaphalocrocis...

Migrants rely on habitat shifts to adapt to changing environments, yet how migratory insect populations cope with global warming remains elusive. Here, we illustrated changes in heat tolerance, reproduction, flight performance, and energy metabolism pathways of a migratory insect Cnaphalocrocis medinalis, a serious pest of rice, induced by heat acclimation, which enhance the capacity to buffer further warming. Compared to natural populations, adults from the heat-acclimated strain exhibited longer heat knockdown time, higher critical thermal maxima, shorter pre-oviposition period, extended oviposition period, and increased fecundity under heat stress. Heat acclimation promoted the take-off behavior at an extremely high temperature and flight distance of adults at normal temperature, and induced a greater number of differentially expressed genes of larvae when exposed to high temperature, particularly genes associated with energy metabolisms. Gene sets related to glycolysis/gluconeogenesis, tricarboxylic acid cycle, oxidative phosphorylation, and pentose phosphate pathway were markedly upregulated in the heat-acclimated larvae. The insulin receptor gene of adults was downregulated in the heat-acclimated strain at normal temperature but significantly upregulated under heat stress which may be involved in energy regulation for migration, reproduction, and heat tolerance. Collectively, our findings demonstrate that migratory populations have an extraordinary capacity to buffer heat stress through energy metabolism-mediated acclimation driven by global warming.