植物根际土壤细菌的分离与鉴定

Isolation and Identification of Bacteria in the Plant Rhizosphere Soil

为了揭示不同植物根际土壤细菌的群落结构和多样性,以期为更好地利用植物根际土壤细菌奠定基础。笔者采用稀释分离法,对12种不同植物的根际土壤细菌进行了分离,并采用16S r DNA序列测定与系统发育分析法初步确定了细菌的分类地位。结果表明,不同种类植物的根际土壤中,可培养细菌的多样性不同,重茬地和多年生植物的根际土壤中细菌的种类和数量较多;12种植物的根际土壤中共分离得到芽孢杆菌属(Bacillus)、假单胞菌属(Pseudomonas)、短杆菌属(Brevibacterium)、节杆菌属(Arthrobacter)、沙雷氏菌属(Serratia)、类芽孢杆菌属(Paenibacillus)、不动杆菌属(Acinetobacter)和Massilia等8个属的137株细菌,其中,芽孢杆菌属为优势属,占81.0%。芽孢杆菌属内占主要比例的有:B.megaterium、B.aryabhattai、B.subtilis、B.amyloliquefaciens等种,其中B.subtilis,B.amyloliquefaciens等细菌种类据文献报道为有益微生物,可以在今后的研究中进行开发和利用。植物根际土壤中的可培养细菌种类丰富多样,有望成为有益微生物资源库进行开发利用。

This study aimed to reveal the community structure and diversity of bacteria in the rhizosphere soilof different plants, and lay the foundation for better utilization of the bacteria in the rhizosphere soil. Thebacteria in the rhizosphere soil of 12 kinds of plants were isolated by dilution method. Based on 16 SrDNA sequence determination and phylogenetic analysis, the taxonomic positions of the bacteria were preliminarydetermined. The results showed that the diversity of culturable bacteria was different in the rhizosphere soil ofdifferent plants. The quantity and species of the bacteria were richer in continuous cropping soil and perennialplant rhizosphere soil. 137 bacteria were isolated from rhizosphere soil of 12 kinds of plants and classified into8 genusis, including Bacillus, Pseudomonas, Brevibacterium, Arthrobacter, Serratia, Paenibacillus,Acinetobacter, and Massilia. The dominant genus was Bacillus, accounting for 81.0%, among which, B.megaterium, B. aryabhattai, B. subtilis and B. amyloliquefaciens accounted for the major proportion. Bacteriaspecies like B. subtilis and B. amyloliquefaciens were reported as profitable soil microorganism, could bedeveloped and utilized in future research, culturable bacteria in plant rhizosphere soil were various and rich in species, and were expected to become a beneficial microorganism pool for future use.