Abstract:[Background] Nujiang Prefecture (Nujiang Grand Canyon), which possess unique geographic conditions and abundant flora and fauna diversity, making great value to study its biodiversity. However, little research have been done to investigate the actinomycetal diversity in this area. [Objective] Research the diversity of soil actinomycetes in Nujiang Grand Canyon. [Methods] High throughput sequencing (Illumina HiSeq platform) was employed to investigate the actinomycetal culture-independent diversity of soil samples. We used several bioinformational figures to making comparison of the differences in actinomycetes composition structure among the seven samples. Meanwhile, the suited culture-dependent isolation methods were determined by tested different pre-treatment methods, undesired bacteria inhibitors and multiple isolation media. [Results] A total of 474 203 bacteria genes and 15 671 OTUs were obtained, the results distributed in 47 phyla, 90 classes, 170 orders, 320 families, 561 genera. Specific to the actinomycetal phylum, high throughput sequencing detected 9 classes, 53 families, 80 genera. The analysis of the diversity between different samples showed that the samples, which called BS, F-G, F-L, L, exhibited better condition than BB，BT，BH. The results showed that 351 actinomycetal strains were obtained from seven soil samples. It belonged to 8 orders, 14 families, 26 genera. YIM171 medium showed the greatest isolation results. The sample of BH exhibited the most rich actinomycetal diversity obviously. [Conclusion] Abundant actinomycetal diversity in this area was mined out by this research. Further bioactivity potential should be tested to offer much more actinomycetal strains for the exploitation of secondary metabolite.
