CROSS-GENERATIONAL PLASTICITY: PARENTAL ENVIRONMENT MODULATES OFFSPRING FITNESS EVIDENCE FROM LIFE-HISTORY TRADE-OFFS IN Mythimna separata (WALKER) - Abdul waheed Solangi; Yunxia Cheng; Lei Zhang; Xingfu Jiang (Journal of Animal and Plant Sciences, 2026)
Cross-generational plasticity, defined as non-genetic parental influences on offspring life history traits, represents a critical but underexplored mechanism in insects’ life-history adaptation. Current study was conducted to investigate how parental temperature (TP), offspring developmental temperature (TD), and offspring adult temperature (TA) interact to influence the offsprings performance in Mythimna separata. Offsprings from low-TP parents showed slower development at low TD, longer pre-oviposition periods, and the highest (331.92±8.04 mg) pupal mass compared with offsprings from high-TP parents 261.11±9.6 mg with significant differences (P≤.0.001). Furthermore, females whose parents were reared at low temperature were heavier, more fecund and had weaker flight abilities than females whose parents were reared at high temperature indicating a trade-off between reproductive investment and dispersal ability with significant differences (P≤0.001). In contrast, progeny from warm parental environments developed more rapidly, matured earlier, and exhibited stronger flight performance with less fecundity. Low TA consistently constrained fecundity and weaker flight ability across treatments, highlighting the importance of within-generation effects of low temperature. Overall, findings revealed that cooler environments favor phenotypes with delayed development (64.98 ± 6.58 Days), higher fecundity (556.96 ± 23.58), and weaker dispersal capacity, whereas warmer conditions promote faster development (30.88 ± 5.36 days), enhanced dispersal, but lower (410 ± 31.56 eggs) reproductive output with significant differences (P≤0.002). These results suggest that cross-generational plasticity mediates adaptive trade-offs between reproduction and dispersal, thereby determining population dynamics and migratory potential. By aligning offspring traits to the thermal conditions experienced by parents, cross-generational temperature effects can strengthen pest survival in changing climates.
Keywords: journal article; Cross generational effects; offspring; temperature; life history traits; flight performance