耐酸铝根瘤菌的筛选及其对大豆-根瘤菌共生体系的影响  

Screening for Al-tolerant Rhizobium and Its Effects on Soybean-Rhizobium Symbiosis System

作　　者：李秀平[1,2] 陈淑珍[2] 黄琮斌 年海[2] 梁诗华 程艳波[2] 牟英辉[2] 

机构地区：[1]广东农工商职业技术学院,广东广州510507 [2]华南农业大学农学院/国家大豆品种改良中心广东分中心,广东广州510642

出　　处：《大豆科学》2018年第1期105-111,共7页Soybean Science

基　　金：国家自然科学基金(31371642);广东省高等职业教育教学改革项目(GDJG2015100);广东农工商职业技术学院重点课题(xyzd1205)

摘　　要：为解决华南大豆种植所面临的土壤酸化问题,筛选出耐酸铝高效根瘤菌,通过回接试验找出适合华南酸性土壤环境的根瘤菌及其共生固氮体系。利用菌株活化培养法分离来自广东增城和惠州地区的20个栽培大豆上的根瘤菌,通过分光光度计检测在酸铝条件下的培养的菌株,筛选出耐性菌株YX30号,并对其生长特性以及接种后对大豆生长的影响。结果表明:在p H4.5及p H6.0条件下含一定浓度铝的营养液中,接种YX30号根瘤菌后,铝浓度为200μmol·L^(-1)时耐酸铝品种华夏1号、PI416937仍能结瘤,桂夏1号和Young不能结瘤。在p H4.5和p H6.0条件下,营养液铝浓度达到100μmol·L^(-1)时,大豆地上部干重均为负增长,铝明显的抑制了大豆的生长;低铝浓度(25和50μmol·L^(-1))条件下,结瘤数均、固氮酶活性、地上部干重及氮含量均高于对照,酸性环境中低浓度的铝能促进结瘤,提高地上部干重和含氮量。In order to solve the soil acidification problem of soybean planting in south China, the superior aluminum-tolerant rhizobia strains were screened by inoculation test, and find the special suitable rhizobial strains or Legume-rhizobium symbiotic nitrogen （ N2 ） fixation （SNF） for acid soil in south China. The nodules of 20 cultivation soybeans which grew in Zengcheng and Huizhou of Guangdong province were isolated by using technique of strains activated culture method. The tolerance of alu- minum was detected by spectrophotometer. The growth characteristics of aluminum-tolerant rhizobium were analyzed by using the method of inoculation. The effects of acid on growth and nodulation of the cultivated-soybean were explored by inoculating with aluminum-tolerant strains. The growth of YX30 strain on pH6. 0 group was faster than the pH4. 5 group under the same A1 concentration. Four soybean genotypes inoculated with rhizobium of YX30 were cultured with different A1 concentration at pH6. 0 and pH4. 5, respectively. Results indicated that when the A1 concentration reached 200 μmol·L-1, the resistant geno- type could nodulate while the sensitive genotype failed. As the concentration of A1 increased, the number of nodules de- creased. A concentration of 100 μmol.L-1 A1 in the medium led to the negative growth of the dry weight of the plant shoots at both pH4. 5 and pH6. 0. In the medium with lower A1 concentration（25 and 50 μmol.L-1 ）, nodule numbers were more than their controls at both pH4. 5 and 6. 0, activity of the N fixation enzyme, dry weight and N content of the shoots were higher than their corresponding controls. Although A1 is an inhibited factor in acid environment, low concentration of A1 could enhance nodulation, and increase the dry weight and N content of the shoots.

关 键 词：大豆 酸铝 根瘤菌 共生 固氮 

分 类 号：S565.1[农业科学—作物学] S157.4