Host specificity of endophytic Pestalotiopsis populations in mangrove plant species of South China

Abstract

For the fact that mangrove plant species are a valuable reservoir of useful metabolites, their endophytes have received increasing attention. We examined the distribution of endophytic Pestalotiopsis associated with mangrove forest from three locations (Guangdong, Fujian, and Hainan province) in South China. Colonization frequencies ofendophytic Pestalotiopsis varied with the place of mangrove plants and host plants. A total of 41, 34, and 76 Pestalotiopsis isolates were obtained and 18, 12, and 27 species were identified from Fujian, Guangdong, and Hainan, respectively. The most common species of endophytic Pestalotiopsis in plants of Fujian province were Pestalotiopsis virgatula,Pestalotiopsis gracilis, and Pestalotiopsis flavidula. The dominant taxa in Guangdong were Pestalotiopsis disseminata; P. flavidula, and Pestalotiopsis sinensis, and the dominant Pestalotiopsis species in Hainan were P. gracilis, Pestalotiopsis crassiuscula, and Pestalotiopsis paeoniae, respectively. The assemblages and dominant species of endophytic Pestalotiopsis varied with the surrounding vegetation and environment. Theisolates, abundance indexes, and Shannon-Weaver diversity index of endophyticPestalotiopsis in Kandelia candel were higher than the others, which were 2.1570, 1.6127, and 2.3368, respectively. However, its evenness index was not the supreme. TheShannon-Weaver diversity index of endophytic Pestalotiopsis showed a positive correlation with abundance indexes, but independent of evenness index. Key words: Endophytic Pestalotiopsis, mangrove, colonization frequencies, diversity, host preference.