东北黑土区大豆根际促生菌群落组成研究

为明确东北黑土区大豆根际促生菌的群落组成,选择内蒙古自治区鄂温克族自治旗、黑龙江省海伦市、黑龙江省克山县和黑龙江省农垦红兴隆农场4个采样点,分析了大豆根际自生固氮菌、解磷菌、溶磷菌和硅酸盐细菌的群落组成,解析了促生菌种与地域之间的对应关系。结果表明:东北黑土区的大豆根际土壤中存在大量促生菌,自生固氮菌达到104cfu.g 1,溶磷菌和解磷菌达到105cfu.g 1,硅酸盐细菌达到103cfu.g 1;分离得到具有自生固氮能力的菌株5株,溶磷菌6株,解磷菌7株,硅酸盐细菌4株;自生固氮菌多样性指数在0.94~1.60之间,溶磷菌多样性指数在0.83~1.52之间,解磷菌的多样性指数在1.07~1.67之间,硅酸盐细菌多样性指数在0.52~0.96之间,4个取样点大豆根际促生菌的多样性指数均大于2。采用对应分析确定了不同地区的典型促生菌,内蒙古鄂温克族自治旗的特征种为自生固氮菌LLN8(Azotobacter beijerinckia indica),黑龙江省海伦市的特征种为溶磷菌DHS13(Micrococcus),黑龙江省克山县的特征种为溶磷菌DHS19(Pseudomo-nas),黑龙江省红兴隆农场的特征种为自生固氮菌LLN1(A.chrooco-ccum)和溶磷菌DHS5(Azotobacter)。同时明确了LLN2(A.azomonas)、LLN6(Bacillus mucilaginosus)、DHS9(Arthrobacter)、DHSO2(Pseudomonas)、DHSO14(Erwinia)、DHSO17(Corynebacterium)和LSJ21(Bacillus)在东北黑土区大豆根际分布较为广泛,这些菌株为研发中国东北黑土区大豆专用型复合生物肥料提供了基础条件。

Community structure of soybean plant growth-promoting rhizobacteriain the black soil region of Northeast China

As the black soil area of Northeast China is major soybean producing areas, it is important for the sustainable development of agriculture to study the soybean plant growth-promoting rhizobacteria (PGPR). For explaining the community structure of soybean PGPR in the black soil region of Northeast China, we chose four sample stations including Ewenki Autonomous Banner in Inner Mongolia Autonomous Region, Hailun City in Heilongjiang Province, Keshan County in Heilongjiang Province and Hongxinglong Farms in Heilongjiang Province, analyzed community composition of nitrogen-fixing bacteria, phosphate-dissolving bacteria, phosphate-solubilizing bacteria and silicate bacteria in soybean rhizosphere, and interpreted correspondence relationship between PGPR strains and areas. The results showed a large number of PGPR in soybean rhizosphere. The quantity of nitrogen-fixing bacteria reached to 104 cfu·g^?1, these of phosphate-dissolving bacteria and phosphate-solubilizing bacteria reached to 105 cfu·g^?1, and that of silicate bacteria reached to 103 cfu·g^?1. Species groups of nitrogen-fixing bacteria, phosphate-dissolving bacteria, phosphate-solubilizing bacteria and silicate bacteria in soybean rhizosphere consisted of 5, 6, 7 and 4 species respectively. Shannon-Weiner biodiversity indices of nitrogen-fixing bacteria, phosphate-dissolving bacteria, phosphate-solubilizing bacteria and silicate bacteria were higher in soybean rhizosphere, which were in ranges of 0.94~1.60, 0.83~1.52, 1.07~1.67 and 0.52~0.96.Biodiversity indices of PGPR were more than 2 in sampling stations. Analysis on correspondence relationship between PGPR strains and areas indicated typical PGPR of different sampling stations. Nitrogen-fixing bacteria LLN8 (Azotobacter beijerinckia indica), phosphate-dissolving bacteria DHS13 (Micrococcus), phosphate-dissolving bacteria DHS19 (Pseudomonas), nitrogen-fixing bacteria LLN1 (A. chrooco-ccum) and phosphate-dissolving bacteria DHS5 (Azotobacter) were typical PGPR strains for Ewenki Autonomous Banner in Inner Mongolia Autonomous Region, Hailun City in Heilongjiang Province, Keshan County in Heilongjiang Province, Hongxinglong Farms in Heilongjiang Province, respectively. The paper cleared that some strains including LLN2 (A. azomonas), LLN6 (B. mucilaginosus), DHS9 (Arthrobacter), DHSO2 (Pseudomonas), DHSO14 (Erwinia), DHSO17 (Corynebacterium) and LSJ21 (Bacillus) were widespread in the black soil area of Northeast China through correspondence analysis, the strains could serve as an important foundation of special compound bio-fertilizer production.