[Objective] The diversity and community structure of endophytic actinobacteria of Melia Toosendan collected from Sichuan and Chongqing were studied for exploring the microbial resources from Chinese medicine Melia Toosendan. [Method] Denaturing gradient gel electrophoresis (DGGE) was employed to analyze endophytic actinobacteria diversity and community structure of Melia Toosendan collected from Wanzhou (Chongqing), Ziyang and Suining, respectively. [Result] The result of DGGE showed the diversity of endophytic actinobacteria that obtained from whether different tissues of Melia Toosendan in one plant or the same tissues collected from different sampling sites were existed different, the main reason was environmental deviation or metabolic differences among plants. The richest diversity of endophytic actinobacteria of Melia Toosendan was observed in bark and the fruit was fewest. The recovery of DGGE strip series showed the 16S rRNA gene sequence similarity between the 24 stronger bands and the typical strains published in Genbank was 91% to 100%，and those sequences belonged to eleven genera, Streptomyces was dominant genera accounting for 25% of all sequences, the remainder belonging to genera Blastococcus, Aeromicrobium, Nakamurella, Mycobacterium, Corynebacterium, Rhodococcus, Cryobacterium, Microbacterium, Nocardioides, Leifsonia, which account for 75%. [Conclusion] This result revealed the endophytic actinobacteria community structure and diversity were different and abundant in different samples.
