Biodiv Sci ›› 2017, Vol. 25 ›› Issue (8): 856-863.DOI: 10.17520/biods.2016348

• Original Papers: Microbial Diversity • Previous Articles     Next Articles

Diversity of Bacillus-like species isolated from potato rhizosphere soils in Yili, Xinjiang

Guohong Liu1, Bo Liu1,*(), Jianmei Che1, Qianqian Chen1, Naiquan Lin2, Weidong Cui3   

  1. 1 Agricultural Bio-Resource Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350003
    2 College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002
    3 Institute of Applied for Microorganism of Xinjiang Academy of Agricultural Sciences, Urumqi 830000
  • Received:2017-03-08 Accepted:2017-06-06 Online:2017-08-20 Published:2017-08-31
  • Contact: Liu Bo

Abstract:

This study aims to understand the diversity of Bacillus-like species found in potato rhizosphere soils in Xinjiang, and provide a basis for mining new resources. Bacillus-like bacteria were isolated from potato rhizosphere soils using the cultivable method and preliminarily identified based on the 16S rRNA gene sequences. The spatial distribution pattern of the Bacillus-like bacteria was analyzed using frequency distribution and number. A total of 349 Bacillus-like isolates were obtained from 30 soil samples, and identified as 66 species belonging to 9 genera and 2 families (Bacillaceae and Paenibacillaceae) within Bacilli by 16S rRNA gene sequences. Sixty six selective strains were chosen to be further analyzed based on colony morphology and 16S rRNA gene sequences, and 14 strains were potential novel species based on the lower similarities found between 93.0-98.5% in their closed references type strains. The species numbers of each genus were 41 for Bacillus (41/66, 62.1%), 9 for Paenibacillus (9/66, 13.6%), 6 for Lysinibacillus (6/66, 9.1%), 4 for Pscychrobacillus (4/66, 6.1%), 2 for Fictibacillus (2/66, 3.0%), and 1 for Brevibacillus, Oceanibacillus, Rummelibacillus and Aneurinibacillus, respectively. In the potato rhizosphere soils, the content range of Bacillus-like species were 2.20-8.86×104 cfu/g. The highest colony content and Bacillus-like species, e.g. 8.86×104 cfu/g and 37 species, respectively, occurred in the Mongolian township of Tekes, while the lowest colony content was found in a stud-farm in Nilka County and the lowest Bacillus-like species (9 species) were found in Xigou Village of Fukang City and on the way from Tekes to Zhaosu County. There was large difference in the distribution of Bacillus-like species in the potato rhizosphere soils, but each site was characterized by the same dominant species, Bacillus simplex and Bacillus aryabhattai. Based on their occurrence frequency, the Bacillus-like species could be discriminated as high frequency species including Bacillus simplex, middle frequency species including Bacillus endophyticus, and low frequency species including Bacillus mycoides. Based on the number of Bacillus-like species, 9 collecting sites were divided into two groups, namely high content and richness and low content and richness. Moreover, there was no significant correlation between the distribution of Bacillus-like species and altitude. Thus, there were many Bacillus-like species in potato rhizosphere soils, which provide rich resources for exploring functional strains.

Key words: Bacillus species, potato rhizosphere soil, diversity