苜蓿根瘤菌抗逆生物学特性研究

Resistance Biological Characteristics of Rhizobium meliloti

为能够筛选抗逆性强、高效共生固氮、有实际应用前景的苜蓿根瘤菌菌株，进行了苜蓿根瘤菌的盐耐受性、温度适应性、酸碱（pH值）耐受性、抗生素抗性、氮素耐受性等抗逆性生物学特性试验。结果表明：苜蓿根瘤菌的耐受的盐浓度为0．5％～2．0％，生长温度范围为18～43℃，酸碱耐受性（pn值）范围为5．0～8．0，抗生素抗性为抗氨苄青霉素、氯霉素、链霉素、四环素，氮素耐受性为NH4NO，浓度100—300mM，苜蓿根瘤菌具有较强的环境适应性。

In order to select the Rhizobium meliloti strains with strong resistance, efficient symbiotic nitrogen fixation and practical application prospects, this paper experimented the salt tolerance, adaptability of temperature, pH（pH） tolerance resistance, antibiotic resistance, and nitrogen tolerance of Rhizobium meliloti. The results showed that： Its salt tolerance was 0.5% to 2.0%, the growth temperature range was 18-43℃, the pH tolerance range was 5.0-8.0, the antibiotic resistance was for ampicillin, chloramphenicol, streptomycin and tetracycline, the nitrogen tolerance was for the NH4NO3 with a concentration of 100 to 300mM, Rhizobium meliloti had a strong environmental adaptability.