| Research on endophytic fungi have been started in the late 19th century, the initial studies are focused on herb, and the relatively little studies on endophytic fungi of forest are limited to some important economic forests, the research on endophytic fungi of conifers are focused on yew, spruce, fir and yew which can produce palitaxel, but the systematic research on endophytic fungi of pinus has not been reported. Pestalotiopsis have long been studied as plant pathogens, but there are a large number of studies showing that pestalotiopsis are important groups of endophytic fungi. Meanwhile, in the study of endophytic Pestalotiopsis, some strains which can produce palitaxel have been isolated from yew. But the systematic research on endophytic Pestalotiopsis of pinus also has not been reported. In this paper, endophytic Pestalotiopsis are isolated from the healthy branches, needles, stems from Pinus elliotii, Pinus massoniana, Pinus yunnanensis, Pinus armandii, Pinus taeda, etc. in meishan, pujiang, mingshan, luding, yibin and lesahn. Identification of morphology and molecular biology,11 species of endophytic Pestalotiopsis are isolated from pine, and biodiversity is analyzed, the taxonomy and molecular phylogenetics are studied to discuss the basis for classification and relationships between pathogenic Pestalotiopsis and endophytic Pestalotiopsis. The results are as follows:1199 strains are isolated from the healthy branches, needles, stems of 2400 tissues of 6 pines,11 species of endophytic Pestalotiopsis are identified on the basis of morphology and molecular biology, the colonization rate is 8.29%. The experimental results show that there are abundant endophytic Pestalotiopsis in the tissues of pinus, the 11 species of endophytic Pestalotiopsis are first isolated from pines in Sichuan, and 2 species are first isolated from pines, P.uvicola and P. gaurae respectively. Besides, endophytic Pestalotiopsis of pines are mostly isolated from Pinus massoniana and Pinus armandii, a few from Pinus elliotii and Pinus densiflora in the published literature, but endophytic Pestalotiopsis of pines are first isolated from Pinus taeda and other Pinus massoniana.2 Biodiversity of endophytic Pestalotiopsis of pines is investigation and analyzed, the experiment results show that the diversity is an obvious difference between 6 species of pinus. By comparison in different plants, the colonization rate of Pinus elliotii, Pinus massoniana and Pinus taeda is obviously higher, and the result is yielded consistent in different altitude comparison. Research on the effect of different tissue on colonization rate shows that tissue specialization is quite obvious, the colonization rate of needles is higher than branches and stems. Research on the effect of different season on colonization rate shows that the colonization rate is highest in spring and autumn, next is summer, winter is minimum.3 By research on taxonomic characters of genus Pestalotiopsis, "PDA+ carnation tissue" is recommended as the identification medium under 25℃, because morphological character is more stable and distinguishing. The color of 3 median cells of conidia, the number of basal and apical appendages of conidia, color of colony, pigment deposition and ring back of the colony are the stable morphological characters. The length and width of conidia, length and width of median cells of conidia, length and width of basal and apical appendages of conidia vary greatly, these characters are not suitable to use as taxonomic characters to distinguish different species.4 A molecular phylogenetic tree is generated by neighbor-joining method in Mega4.0 with the ITS rDNA sequences of endophytic Pestalotiopsis, which are isolated from the healthy branches, needles, stems of 6 pines, and some sequences of pathogenic Pestalotiopsis are downloaded from NCBI, evolutionary relationship is discussed on the basis of molecular level, and the relationships between pathogenic Pestalotiopsis and endophytic Pestalotiopsis are analyzed.
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