Genome Duplication Reshapes Leaf Structure and Trait Coordination in Mangoes (Mangifera indica L.)

Polyploidy is increasingly recognized as a mechanism enhancing physiological resilience in woody fruit crops, yet its functional consequences remain poorly understood in mangoes (Mangifera indica L.), a major tropical species expanding into water-limited environments. Because leaf structure underpins plant water relations and gas exchange, this study evaluated how genome duplication alters foliar traits by comparing diploid and autotetraploid individuals of three polyembryonic cultivars (Gomera-1, Gomera-3, and Kensington Pride). Morphological and anatomical analyses revealed consistent ploidy-related modifications. Autotetraploids exhibited enlarged stomatal guard cells, increased leaf thickness, and changes in mesophyll organization, indicating greater structural investment in leaf tissues. These features are commonly associated with structural strategies that may contribute to water retention and hydraulic regulation, although their direct physiological consequences were not evaluated in the present study. Overall, our results indicate that genome duplication substantially modifies leaf structural traits in mangoes, although the magnitude and direction of these responses were cultivar-dependent. This study provides new insights into how polyploidy reshapes leaf morphology and anatomy in mangoes and advances our understanding of polyploid-induced structural variation in perennial fruit crops.