高寒地区红豆草根瘤菌抗逆性研究

Research on stress resistence of sainfoin rhizobium in alpine region

从甘南合作、甘南夏河桑科的红豆草(Onobrychis vicilfolia)根系中分离培养得到28个根瘤菌菌株,针对各菌株的耐盐性、耐酸碱及其泌酸碱能力进行研究,结果表明:采集于桑科的红豆草根瘤编号STD111ⅠA、STD26ⅠB、STD411ⅠB、STF11ⅡA的菌株耐盐性极强,在10%NaCl培养基上正常生长;采集于合作的红豆草根瘤菌株HND26ⅠA、HND26ⅠB、HND26Ⅱ和桑科红豆草根瘤菌株STD111ⅠA、STD26ⅠB、STD411ⅠA、STD411ⅡA耐酸性最强,能在pH4.0的培养基上正常生长;耐碱性最强的是夏河地区菌株STF11ⅢA,可以在pH12.0的培养基上正常生长.进一步试验表明,菌株HND26ⅠA、HND26ⅠB、HND26Ⅱ、STD111ⅠA和STD26ⅠB既能抗pH 4.0的酸逆境,又能抗pH11.0的碱逆境.同时研究发现,菌株耐碱性的强弱与其泌酸能力相关.

28 rhizobia strains were isolated from sainfoin roots from Hezuo and Sangke in Gansu Province, the salt-resistance, acid-alkali resistance and acid-alkali secreting ability of each strains were studied. The results showed that sainfoin rhizobia strains numbered as STD111 I A, STD26 I B, STD411 I B, STFll 11 A which collected from Sangke area had the strongest salt-resistant ability, and all of them could regularly grow in 10 % NaC1 medium; sainfoin rhizobia strains numbered as HND26 I A, HND26 I B, HND26 I] which collected from Hezuo area and STD111 I A, STD26 I B, STD411 I A, STD411 II A from Sangke area had the strongest acid-resistant ability, and these strains could regularly grow in medium with pH value of 4.0;the strain numbered as STF11Ⅲ A from Xiahe area owns the strongest alkali-resistant ability,and it could regularly grow in medium with pH value of 12. 0. A further experiment indicated thatstrains numbered as HND26 I A, HND26 I B, HND26 Ⅱ, STD111 I A and STD26 I B could resist both acid stress with pH value of 4. 0 and alkali stress with pH value of 11.0. Meanwhile,the ability of alkali resis tenee was correlated to the ability of acid secreting.