【目的】对一株来源于广西甘蔗根际土壤的高效解无机磷细菌BS06的分类和解磷能力进行探讨,以期为解磷微生物在广西甘蔗生产上的开发和应用提供理论依据。【方法】通过形态观察、生理生化测定及16S r RNA基因序列同源性分析,进一步结合种特异的rec A基因序列分析对解磷菌BS06进行分类鉴定;通过改变无机磷培养基中的碳源、氮源对菌株解磷能力的影响,分析菌株的解磷特性;通过盆栽试验了解菌株对甘蔗品种粤糖00236、桂糖28磷素吸收的影响。【结果】分类鉴定结果表明菌株BS06属于洋葱伯克霍尔德菌(Burkholderia cepacia);菌株在以乳糖为碳源条件下具有较强的解磷能力,其发酵液中水溶性磷含量为262.71 mg/L;在以硝酸钠为氮源条件下有较强解磷能力,其发酵液中水溶性磷含量达到305.85 mg/L;接种BS06菌株显著促进甘蔗组培苗的生长并提高甘蔗植株的含磷量。【结论】解磷细菌BS06具有较大的开发利用潜力。
[Objective] The purpose of the present study was to investigate the phosphate-solubilizing ability of a bacterial stain BS06, for developing and applying effectively phosphate-solubilizing microbes in sugarcane production in Guangxi. [Methods] 16S rRNA gene sequence homology comparison, recA gene analysis as well as morphological, physiological and biochemical analyses were carried out to identify the bacterial strain BS06. The phosphate-solubilizing ability of BS06 was investigated under the conditions of changing the carbon and nitrogen source, separately in inorganic phosphate medium. [Results] The strain BS06 was identified as Burkholderia cepacia. The strain had high and efficient phosphate-solubilizing ability under the condition of carbon source with lactose and nitrogen source with sodium nitrate separately, and the concentration of water soluble phosphorus in fermentation solution was 262.71 mg/L and 305.85 mg/L, respectively. Compared with the uninoculated controls, BS06 significantly increased dry weights and phosphorus contents of micropropagated sugarcane seedlings. [Conclusion] The bacterial strain BS06 had high potential of exploitation.