Effects of agarwood formation induced by Fusarium sp. A2 on distribution and community composition of endophytic fungi in leaves of Aquilaria sinensis

The aim of the paper is to observe the distribution of the endophytic fungi in leaves of Aquilaria sinensis by using permanent paraffin-cut section, optical microscope photography and histochemistry. Total DNA was extracted with modified CTAB method and rDNA ITS regions of plant and endophytic fungi were amplified with eukaryotic universal primers. The rDNA ITS amplicon was characterized by RFLP analysis, sequencing of rDNA ITS library and phylogenetic analyses using PAUP by maximum parsimony. Fusarium sp. A2 was used to induce the formation of resinous in A. sinensis trees. As a result, endophytic fungi mainly distributed in spongy and phloem in leaf. Endophytic fungi distributed in the phloem in agarwood-producing tree and had a relatively high abundance. Phoma sp. and Collectrotrichum sp. were the absolute advantage species in the leaf tissues of non-resinous and agarwood-producing tree, respectively. Collectrotrichum sp. was the only fungal species detected both in the two types of A. sinensis with different levels of abundance. The culture-independent molecular method can be used to identify fungal species directly and rapidly from the plant tissues. Endophytic fungal communities in non-resinous and agarwood-producing A. sinensis leaf tissues were quite different.