J Syst Evol ›› 2008, Vol. 46 ›› Issue (3): 391-395.DOI: 10.3724/SP.J.1002.2008.08023

• Research Articles • Previous Articles     Next Articles

Molecular evidence for natural hybridization between Sonneratia alba and S. griffithii

1Suo QIU, 1Ren-Chao ZHOU, 2Yun-Qin LI, 3Sonjai HAVANOND, 3Chanop JAENGJAI, 1Su-Hua SHI*

  

  1. 1(State Key Laboratory of Biocontrol and Key Laboratory of Gene Engineering of the Ministry of Education, Sun Yat-Sen University, Guangzhou 510275, China)

    2(Experimental Center of Fundamental Teaching, Zhuhai Campus, Sun Yat-Sen University, Zhuhai 519802, China)

    3(Department of Marine and Coastal Resources, Phayathai, Bangkok 10400, Thailand)
    lssssh@zsu.edu.cn
  • Received:2008-02-20 Published:2008-05-18

Abstract: Interspecific hybridization has been frequently observed in the mangrove genus Sonneratia. However, no natural hybridization has been reported between Sonneratia alba and S. griffithii to date, despite their overlapping distribution in the coast of Andaman Sea. In this study, cysteine proteinase inhibitor gene (cpi) from the nuclear genome, and two intergenic spacers (trnL-trnF and trnV-trnM) from the chloroplast genome, were sequenced to determine whether natural hybridization took place between the two species. Our results revealed two distinct types of cpi sequences from the putative hybrid matching those acquired from S. griffithii and S. alba, respectively. Sequencing of the chloroplast trnL-trnF and trnV-trnM regions showed that S. alba differed from S. griffithii by one nucleotide in each region, and the putative hybrid had the identical sequences with S. griffithii. Molecular data demonstrated clearly that there indeed existed natural hybridization between S. alba and S. grif-fithii, and that S. griffithii was the maternal parent in this hybridization event.

Key words: chloroplast DNA, mangroves, natural hybridization, nuclear gene, Sonneratia