【摘要】 【目的】研究解盐促生细菌Rs-5和Rs-198的生理特性及其在盐胁迫下对棉花发芽的影响,并进一步探讨两株菌的促生性能。【方法】利用钼锑抗比色法和Salkowski法分别测定细菌培养液中可溶性磷和IAA(吲哚-3-乙酸)的含量,并通过盆栽试验检测两株菌对棉花发芽的影响。【结果】经菌株的生理生化初步鉴定,菌株Rs-5和Rs-198分别归属克雷伯氏菌属(Klebsiella sp.)和假单胞菌属(Pseudomonas sp.)。两株菌处理棉花种子后,种子在含盐土壤中的发芽率分别比对照提高了26.3%和34.4%。在无机磷培养基中菌株Rs-5和Rs-198都具有溶解磷酸三钙的性能,可溶解磷的最大含量分别达到了73.38和82.41mg·L-1,培养基的pH分别由7.48降到5.22和4.54。在测定IAA的分泌试验中,菌株Rs-5和Rs-198培养液中的IAA含量在96h分别达到了7.09和10.77mg·L-1,并一直保持较高水平。【结论】两株菌的产酸溶磷与分泌生长素的性能是在盐胁迫下提高棉花发芽和出苗率的主要原因。更多还原

【Abstract】 【Objective】 The physiological characters of two bacteria strains, Rs-5 and Rs-198, were studied. 【Method】 Cotton seeds germination were tested in a pot experiment. Spectrophotometrically with Mo-Sb-VC method and Salkowski method were used to determine content of solubilizing tricalcium phosphate and IAA, respectively. 【Result】 The two bacteria strains Rs-5 and Rs-198 were classified as Klebsiella sp. and Pseudomonas sp., respectively. The germination rates of cotton seeds treated by the two strains were improved by 26.3 % and 34.4 % compared with the control. During seven days fermentation, the soluble phosphate contents dissolved by the strains Rs-5 and Rs-198 in fermentation broth reached to 73.38 mg·L-1 after incubating for 24 hours and 82.41 mg·L-1 after 48 hours, respectively. The pH value in fermentation broth of the two strains decreased from 7.48 to 5.22 and 4.54, respectively. IAA secreted by Rs-5 and Rs-198 in cultures were accumulated following the incubation time. The content of IAA were accumulated to 7.09 mg·L-1 and 10.77 mg·L-1 at 96 hours of fermentation. 【Conclusion】 Phosphate solubilizing, organic acids production and IAA secretion by strains Rs-5 and Rs-198 might be the reasons for promoting cotton germination under salt stress.更多还原