根际溶磷伯克霍尔德菌Paraburkholderia spp.对马尾松苗的促生作用  

Growth Promoting of Pinus massoniana Seedlings Regulated by Rhizosphere Phosphate-solubilizing Paraburkholderia spp.

作　　者：徐红云 吕俊 于存[2] XU Hong-Yun;LV Jun;YU Cun(College of Eco-Environment Engineering,Guizhou Minzu University,Guiyang 550025;College of Forestry,Guizhou University,Guiyang 550025)

机构地区：[1]贵州民族大学生态环境工程学院,贵阳550025 [2]贵州大学林学院,贵阳550025

出　　处：《生物技术通报》2023年第6期274-285,共12页Biotechnology Bulletin

基　　金：国家自然科学基金项目(32160375);贵州省科技计划项目(黔科合基础[2022]一般210)。

摘　　要：为筛选溶磷效果较好的根际细菌(phosphate-solubilizing rhizobacteria,PSB),并明确其对马尾松苗的促生效果和作用机制。利用土壤稀释平板法进行PSB菌株的分离和纯化,通过形态学和16S rDNA分子测序等方法进行PSB菌株的鉴定,最后将PSB菌株接种至马尾松苗,培养60 d后测定马尾松苗生长、生理、苗根际土壤理化性质和根际细菌群落结构和组成。结果表明:由马尾松根际土中分离获得溶磷能力较强的3个PSB菌株WJ10、WJ25和WJ41均为伯克霍尔德菌Paraburkholderia spp.;3个PSB菌株对磷酸铝的增溶能力最强,其次是磷酸三钙、磷酸氢钙和磷酸铁;盆栽试验表明,3个PSB菌株均可促进幼苗的生长,其中WJ25对苗高、根长的促进效果最明显,WJ41和WJ10次之。3个PSB菌株对苗促生的主要机制包括,PSB提高了马尾松苗的根系活力、叶绿素b、可溶性蛋白等生长指标及氮、磷和钾等养分含量;同时,提升了根际土有效磷、速效钾、活性氮、土壤养分含量、土壤酶活性;此外,3个PSB菌株的添加还影响了马尾松苗根际细菌群落的组成和多样性,促进了Bacillus、Nitrosospira、Gemmata和Cytophaga等有益菌在根际土壤中的显著富集。综上,本研究筛选获得的3个溶磷伯克霍尔德菌,它们能够通过调控植物生理及改变根际微环境从而促进马尾松苗的生长。通过本研究,为马尾松根际溶磷细菌菌肥的开发和应用提供了理论依据。It is aimed to screen phosphate-solubilizing rhizobacteria(PSB)and to clarify its growth-promoting effect on Pinus massoniana seedlings and the mechanism.The soil-dilution plate method was used to isolate and purify the PSB strains.The PSB strains were identified by morphology and 16s rDNA sequencing methods.Finally,the masson pine seedlings were inoculated with PSB strains for 60 d,then the seedling growth and physiological indexes,soil physical and chemical properties,and rhizosphere bacterial community were determined.The results showed that three PSB strains(WJ10,WJ25 and WJ41)with strong phosphate-solubilizing abilities were isolated from the P.massoniana rhizosphere soil and belonged to Paraburkholderia spp.The three PSB strains had the strongest phosphate-solubilizing abilities to aluminum phosphate,followed by tricalcium phosphate,calcium monophosphate and ferric phosphate.Based on the pot experiment,the three PSB strains effectively promoted seedlings growth,with the best effects on the seedling height and root length promotion for WJ25,followed by WJ41 and WJ10.The main mechanisms of seedling promotion of the three PSB strains include:1)The PSB strains increased the root activity,chlorophyll b,soluble protein,nitrogen,phosphorus and potassium contents in masson pine seedlings;2)meanwhile,PSBs enhanced the contents of available phosphorus,available potassium,active nitrogen,soil urease and phosphatase in rhizosphere soil;3)in addition,the addition of three PSB strains also affected the composition and diversity of the rhizosphere bacterial community,and promoted the significant enrichment of beneficial bacteria such as Bacillus,Nitrosospira,Gemmata and Cytophaga in the rhizosphere soil.In conclusion,the three Paraburkholderia spp.strains could promote masson pine seedlings growth by regulating plant physiology and changing rhizosphere microenvironment.This study provides a theoretical basis for the development and application of rhizosphere PSB fertilizer of P.massoniana.

关 键 词：根际溶磷细菌 促生 伯克霍尔德菌 马尾松 根际微生物 

分 类 号：S791.248[农业科学—林木遗传育种]