杨梅园土壤优势放线菌的分离及其防病促生功能  

Isolation of Dominant Actinomycetes from Soil of Waxberry Orchards and Its Disease Prevention and Growth-Promotion Function

作　　者：王炫栋 宋振 兰赫婷 江樱姿 齐文杰 刘晓阳 蒋冬花[1] WANG XuanDong;SONG Zhen;LAN HeTing;JIANG YingZi;QI WenJie;LIU XiaoYang;JIANG DongHua(College of Chemistry and Life Science,Zhejiang Normal University,Jinhua 321004,Zhejiang)

机构地区：[1]浙江师范大学化学与生命科学学院,浙江金华321004

出　　处：《中国农业科学》2023年第2期275-286,共12页Scientia Agricultura Sinica

基　　金：浙江省基础公益研究计划(LGN22C140004);浙江省大学生科技创新活动计划(新苗人才计划)(2022R404B052)。

摘　　要：【目的】分离、筛选杨梅园植物根系和根际土壤优势放线菌,探究放线菌种群数量与分布的季节性特征,分析其在生物防治与促进植物生长上的应用潜力。【方法】采集不同季节杨梅园内植物根系及根际土壤样品,采用稀释平板法进行优势放线菌的分离纯化。采用选择培养基分析优势放线菌固氮、溶磷、解钾等植物根际促生菌(PGPR)特性,CAS平板检测铁载体产生能力,Salkowski显色法检测吲哚乙酸(IAA)产生能力,比色法检测ACC脱氨酶活性。对具备优良促生特性的菌株进行试管促生效应鉴定,并采用平板对峙法和发酵液牛津杯法分析其抗菌活性。最后,对特性良好的菌株通过形态观测、生理生化试验和16S rDNA序列分析确定其分类地位。【结果】从不同海拔的两个杨梅园中共分离到优势放线菌127株,其中植物根系32株、根际土壤95株。与春、夏季相比,秋、冬季分离到的放线菌数量较多种类较丰富,抑菌和促生能力较强。且高海拔地区分离的优势放线菌数量在春、夏两季显著多于低海拔地区,而秋、冬季低海拔地区分离到的放线菌数量超过高海拔地区,并且远超该地区春、夏两季分离到放线菌的总数。最终得到46株不同种类放线菌,经过PGPR特性分析,35株放线菌具有明显的促生特性。其中菌株Sz-11具备固氮、溶无机磷、溶有机磷、产生铁载体、产生IAA及产生ACC脱氨酶6种促生特性,试管鉴定结果显示其能有效促进水稻幼苗生长发育,接种菌株Sz-11的幼苗株高及根长增幅分别为36.08%和22.70%。同时,菌株Sz-11对多种植物病原细菌均表现出较好的拮抗活性,对水稻白叶枯病菌(Xanthomonas oryzae pv.oryzae,Xoo)、水稻细菌性条斑病菌(Xanthomonas oryzae pv. oryzicola,Xooc)拮抗作用较为显著且稳定。通过一系列观测、试验结合测序分析结果,初步鉴定为沙阿霉素链霉菌(Streptomyces zaomyceticus)。【结论【Objective】The objective of this study is to isolate and screen the dominant actinomycetes from plant roots and rhizosphere soils in waxberry orchards, explore the seasonal characteristics of the number and distribution of actinomycete populations, and to analyze its application potential in biological control and plant growth promotion.【Method】Samples of plant roots and rhizosphere soils were collected in different seasons from waxberry orchards, and the dominant actinomycetes were isolated and purified by the dilution plate method. Selective media were used to analyze the plant growth-promoting rhizobacteria(PGPR) characteristics of dominant actinomycetes such as nitrogen fixation, phosphorus solubilization, and potassium solubilization.The CAS plate assay was used to detect siderophore production capacity. The Salkowski assay was used to detect IAA production capacity. The colorimetric method was used to detect ACC deaminase activity. The strains with excellent growth-promoting characteristics were identified by test tubes for pro-biogenesis, and their antibacterial activity was analyzed by the flat-confrontation method and the Oxford cup method. Finally, the taxonomic status of the strain with good characteristics was identified by morphological observation, physiological and biochemical tests, and 16S rDNA sequence analysis.【Result】A total of 127 strains of dominant actinomycetes were isolated from two waxberry orchards at different altitudes, including 32 from plant roots and 95 from rhizosphere soils. Compared with those isolated in spring and summer, the actinomycetes isolated in autumn and winter had greater quantity and variety, stronger inhibition and promotion ability. The number of dominant actinomycetes isolated at higher altitudes was significantly higher than at lower altitudes in spring and summer, while in autumn and winter the number of actinomycetes isolated at lower altitudes exceeded that of higher altitudes and far exceeded the total number of actinomycetes isolated in spring an

关 键 词：杨梅 放线菌 植物根际促生菌 生物防治制剂 生物肥料 

分 类 号：S667.6[农业科学—果树学] S154.383[农业科学—园艺学]