Intra-Individual Floral Variation in Tropical Andromonoecious Tree

Intraindividual variation in floral traits is central to plant reproductive dynamics, yet within-crown patterns in tropical andromonoecious trees remain underexplored. We used dwarf cashew (Anacardium occidentale L.) as a model to test three predictions: (i) floral output and sex ratio differ among crown quadrants due to microenvironmental gradients; (ii) male and hermaphroditic flowers show divergent phenological dynamics; and (iii) flowering abundance does not necessarily predict fruit set. We monitored 120 panicles per bloom across two flowering flushes in two years. Flowering intensity clustered early within the reproductive cycle and varied little between years, indicating stronger effects of within-flush timing than of broad seasonal context. Emission patterns of male and hermaphroditic flowers diverged, with male flowers requiring longer to reach anthesis. The north quadrant exhibited more hermaphroditic flowers, consistent with greater solar exposure, whereas fruit production peaked in the east and west quadrants, revealing a spatial decoupling between flowering and fruiting. We also observed protandrous dichogamy. These results show that within-crown microclimate and architectural position structure intraindividual floral variation and that post-floral filters help determine fruit set. Consequently, flowering alone is a poor proxy for reproductive success, underscoring the need to integrate positional, temporal, and post-floral processes when evaluating reproductive performance.