MOLECULAR EVIDENCE FOR NATURAL HYBRIDIZATION IN THE MANGROVE GENUS AVICENNIA

摘要

Hybridization has been observed in several multi-species genera of mangroves; however, there has been no report onhybridization in Avicennia in the Indo-West Pacific region. In this study, we sequenced 5 low-copy nuclear genes ofAvicennia marina, A. rumphiana and 2 individuals of their putative hybrid in the Southeast Asia region to test the hypothesisof natural hybridization between these 2 species. We demonstrated that both putative hybrid individuals possessed two typesof sequences at each of the 5 genes, perfectly corresponding to those of A. marina and A. rumphiana, confirming thehybridization between these 2 Avicennia species, and the 2 hybrid individuals are most likely F1 hybrids. Sequencing of thechloroplast trnH-psbA regions indicated that A. marina was the maternal parent of the two hybrid individuals.