Comparing the reproductive biological characteristics of the alien invasive Coreopsis lanceolata to those of the non‐invasive alien congener Coreopsis tinctoria

Abstract

AbstractIt is important to determine the characteristics associated with the success of alien species. However, there is no universal syndrome of invasion reproductive characteristics to explain the success of invasiveness has not been identified. Comparative studies on congeneric successful or non‐successful alien species are beneficial for revealing the drivers of invasion success and predicting future distributions. Reproductive biological characteristics, including the mating system, phenology of flowering, floral syndrome, pollination biology and seed germination have been investigated in the invasive Coreopsis lanceolata and non‐successful congener alien species Coreopsis tinctoria. The results revealed that C. lanceolata significantly attracted insect visitors by 11.67 times more than its congener, and the corolla density of C. lanceolata was positively correlated with the number of visiting insects. The high attraction of local insect bees Apis cerana guarantees the reproductive success and high seed production of C. lanceolata. Nevertheless, there was no versatile mating system, because its congener non‐successful alien species C. lanceolata still successfully invaded due to the combination strategies of self‐compatibility and presence of rhizomes. Furthermore, the ability of seed germination of C. lanceolata was lower than that of C. tinctoria, especially under drought and Al3+ stress, suggesting that germination performance can serve as a reference indicator. However, this was not an absolute trait for invasiveness. Hence, these germination traits might slow down the invasiveness of C. lanceolata in south China. These present findings highlight that the combination of self‐incompatibility and rhizomes should be given attention in the risk assessment protocols for plant invasiveness.