Unraveling the molecular basis of andromonoecy induction under heat stress conditions in Solanum melongena
Abstract
Climate change poses a significant challenge to global agriculture, and the Mediterranean region is particularly susceptible to its adverse effects. In this context, understanding plant responses to stress becomes imperative for mitigating yield losses. Several species of the genus Solanum, exhibit andromonoecy, a sexual system characterized by the coexistence of hermaphroditeand male flowers. Specifically, Solanum melongena displays functional andromonoecy, where“male” flowers possess a non-functional gynoecium because the reduced development of the stigma andthe style avoids the fertilization of the ovules. Under heat stress conditions, there is an observed increasein functionally-male flowers, suggesting that this increase is a mechanism to optimize resource allocationin response to environmental challenges. Our lab developed an early-flowering, dwarf eggplant variety,(“Micromel,”) more amenable for molecular studies. Utilizing Micromel plants, we performed transcriptomic and metabolomic analyses on pistils of flowers grown under control or heat stress conditions. Our findings reveal that heat stress induces autophagy, contributingto the increase of functionally-male flowers. Understanding the molecular mechanisms underlyingthe induction of functional andromonoecy in response to heat stress not only provides insights intoplant reproductive strategies but also offers avenues for enhancing stress tolerance in agricultural systems. By deciphering how plants allocate resources under stress, we can develop strategies to mitigate the impacts of climate change on plants both for agricultural and conservation purposes.