Clone-specific phenotypic plasticity under constant darkness and competition reveals surprising aphid resilience

This preprint describes a striking clone-specific aphid resilience and survival in the absence of light as a Zeitgeber and under competition. Pea and black bean aphids reared on light-deprived faba bean host plant expressed differential reproductive and phenological plasticity that varied across the clones, especially when the target pea aphid clone (N116) was in competition with a conspecific or a heterospecific. Moreover, aphid responses to the complex stress applied varied on a molecular level whereby the expression of heat shock protein 70 (Hsp 70) peaked in the dark particularly in N116 alone and in intraspecific competition. Notable changes in fingerprint metabolites as well as C:N ratio differed across treatments and the conditions of the experiment. This work documents varying aphid resilience, underscoring counterintuitive survival on etiolated host plants that suffered from chlorosis in constant darkness. The insights we provide have implications for exploring previously unknown aspects of phenotypic plasticity and tolerance in aphids, which are crucial to survival in crunching anomalous environments.