Effect of Insect Damage on Seed Germination of Black Locust ( Robinia pseudoacacia )

ABSTRACT Black locust ( Robinia pseudoacacia ) exhibits cryptic seed heteromorphism, in that the seeds are morphologically uniform but vary in dormancy. To evaluate the influence of insect damage on seed dormancy, in this study, pods were either enclosed by insect‐proof nets or remained uncovered as a control. The bagged pods had significantly less insect damage, more mature seeds, and a higher seed germination rate. In contrast, the exposed pods had more damaged and immature seeds, and a higher proportion of seeds rotted during germination tests. Even after 8 years, dormant seeds from the bagged pods showed higher germination rates, suggesting that insect damage negatively impacts long‐term seed viability. This study indicates that insect activity, even if not visually obvious, may contribute to the seed dormancy of black locust. The results suggest that insect damage contributes to cryptic seed heteromorphism, as protected seeds displayed a higher frequency of dormancy.