生物技术通报 ›› 2020, Vol. 36 ›› Issue (8): 45-52.doi: 10.13560/j.cnki.biotech.bull.1985.2020-0114

• 研究报告 • 上一篇    下一篇

巨大芽孢杆菌ZS-3溶无机磷机制及其对樟树的促生作用

钱婷, 叶建仁   

  1. 南方现代林业协同创新中心 南京林业大学林学院,南京 210037
  • 收稿日期:2020-02-08 出版日期:2020-08-26 发布日期:2020-08-27
  • 作者简介:钱婷,女,硕士研究生,研究方向:微生物学;E-mail:1837843671@qq.com
  • 基金资助:
    国家林业行业公益项目(201304404),江苏林学优势学科资助项目

The Mechanism of Dissolving Inorganic Phosphorus by Bacillus megaterium ZS-3 and Its Growth Promotion of Cinnamomum camphora

QIAN Ting, YE Jian-ren   

  1. Co-Innovation Center for Sustainable Forestry in Southern China,College of Forestry,Nanjing Forestry University,Nanjing 210037
  • Received:2020-02-08 Published:2020-08-26 Online:2020-08-27

摘要: 旨在探究巨大芽孢杆菌ZS-3菌株溶无机磷特性和相应的溶磷机制,为利用和提高其改善土壤中难溶磷资源的利用率提供理论依据和技术途径。通过NBRIP培养基、钼锑抗比色法、稀释涂布法、酸碱滴定法等方法测定菌株的溶磷量、菌落生长情况和可滴定酸度,通过扫描电镜(SEM)观察Ca3(PO42表面形态特征,通过高效液相色谱法和对硝基苯磷酸二钠法测定发酵液中有机酸种类、含量和磷酸酶活性,选择2种不同类型的土壤,通过盆栽实验测定菌株ZS-3对樟树生长及土壤理化性质的影响。结果显示,菌株ZS-3在连续培养168 h期间最大溶磷量出现在培养96 h时,为188 µg/mL;菌体数量最大达2.34×109 CFU/mL,出现在培养72 h时;培养初期24 h内pH下降速度最快,从初始8.06降至5.14,可滴定酸度呈缓慢上升趋势。SEM实验表明菌株ZS-3与Ca3(PO42作用后能使其表面变得凸凹不平。ZS-3的溶磷过程中酸性磷酸酶和碱性磷酸酶活性较低。ZS-3在培养过程中会产生大量有机酸,以外泌乙酸和甲酸为主,含量分别为484.12 ng/μL和255.1 ng/μL;施菌处理对2种不同类型土壤栽种的樟树都具有促生作用,土壤速效磷含量均提高且低磷土壤速效磷含量增长量更显著。菌株ZS-3能够高效溶解无机磷,促进樟树生长,有望为溶磷微生物肥料的开发提供物质资源。

关键词: 巨大芽孢杆菌, 溶磷微生物, 有机酸, 促生作用

Abstract: The purpose of this study is to explore the inorganic phosphorus-dissolving characteristics and corresponding phosphorus-dissolving mechanism of Bacillus megaterium ZS-3,and to provide a theoretical basis and technical approach for utilizing and improving the utilization rate of poorly soluble phosphorus resources in soil. NBRIP medium,molybdenum anti-colorimetric method,dilution coating method,and acid-base titration method were applied to determine the amount of phosphorus solubilized,colony growth and titratable acidity of the strain. Scanning electron microscope(SEM)was used to observe the surface morphology of calcium phosphate Ca3(PO42. High performance liquid chromatography and p-nitrophenyl phosphate disodium were adapted to measure the types of organic acids,content and activity of phosphatase in the fermentation broth. Selecting 2 different types of soil for pot experiments,the effects of strain ZS-3 on the growth of Cinnamomum camphora and the physicochemical properties of soil were checked. As results,the maximum amount of dissolved phosphorus by strain ZS-3 occurred at 96 h with 188 μg/mL when it was continuously cultured for 168 h. The maximum number of cells reached 2.34×109 CFU/mL at 72 h. The pH dropped the most quickly at early 24 h from initial 8.06 to 5.14. The titratable acidity was slowly increasing. SEM experiment showed that the strain ZS-3 caused the calcium phosphate surface uneven and rough after interacting with it. The activities of acid phosphatase and alkaline phosphatase were low during the dissolution by ZS-3. A large amount of organic acids were generated during the ZS-3 culturing,mainly acetic acid and formic acid,their contents were 484.12 ng/μL and 255.1 ng/μL,respectively. The application of strain ZS-3 promoted the growth of C. camphorain planted in two different types of soil. The soil available phosphorus content increased and there was more significant increase of available phosphorus content in low phosphorus soil. In sum,the strain ZS-3 can efficiently dissolve inorganic phosphorus and promote the growth of C. camphora,and is expected to provide resources for the development of phosphorus-solubilizing microbial fertilizer.

Key words: Bacillus megaterium, phosphorus-dissolving microorganism, organic acid, growth-promoting effect