马西利亚菌B260的分离鉴定及促进育苗的效果

Isolation and Identification of Massilia sp. B260 and Its Effect on Seedling Raising

马西利亚菌广泛分布于植物根际,但目前仍缺乏其促进育苗效果的研究。分析马西利亚菌株 B260 促进育苗效果,以期为该菌株的实践应用提供理论依据。以涂布划线分离培养根际细菌;基于 16S rRNA 基因序列同源性分析,对菌株进行初步分类鉴定;基于选择性培养基分析菌株的固氮、解植酸磷、解无机磷、产 ACC 脱氨酶、产铁载体和产 IAA 等植物促生性状和能力;设置 2 组处理(含基质中添加菌株 B260 的处理,pB260;不添加 B260 的空白处理,CK);采用穴盘育苗比较分析不同处理下番茄、黄瓜、甘草及黄芪的幼苗生长性状。菌株 B260 的 16S rRNA 与 Massilia plicata 76T 的相似性最高(99.85%),初步确定其为马西利亚菌;B260 具有含固氮、解磷、产激素、产铁载体和 ACC 脱氨酶在内的植物促生性状,其中固氮和解无机磷的能力较强;相比CK,pB260 提高了番茄、黄瓜、甘草和黄芪的发芽率、株高、根长、干重和鲜重,特别是根长分别提高了 6.71%、5.41%、12.28%和 15.79%。菌株 B260 为马西利亚菌(Massilia),具有多种植物促生性状,可促进育苗并作为育苗基质用菌种。

Massilia strain is widely distributed in the rhizosphere of plants;however,there is still a lack of research on its effect on promoting seedling. To analyze the effect of Massilia strain B260 on promoting seedling growth is aimed to provide theoretical basis for its practical application. Coating and scribing was used to isolate the rhizosphere bacteria. The homology analysis of 16S rRNA gene sequence was based to preliminarily classify and identify the strains. The selective medium was used to analyze the characters and abilities of strains fixing nitrogen,dissolving phosphorus phytic acid and inorganic phosphorus,producing ACC deaminase,iron carrier and IAA. Two groups of treatments(including pB260 of adding strain B260 in the matrix,CK without adding B260)were set up. The seedling growth characters of tomato,cucumber,licorice root and astragalus under 2 treatments in hole plate seedling raising were compared and analyzed. The 16S rRNA of strain B260 had the highest similarity(99.85%)with Massilia plicata 76T,which was preliminarily identified as Massilia. B260 demonstrated the plant growth-promoting character including nitrogen fixation,phosphorus release,hormone production,iron carrier production and ACC deaminase production,among which nitrogen fixation and inorganic phosphorus decomposition were the strongest. Compared with CK, pB260 increased the germination rate,plant height,root length,dry weight and fresh weight of tomato,cucumber,licorice and astragalus, especially root length increased by 6.71%,5.41%,12.28% and 15.79%,respectively. The B260 strain is Massilia,which has traits of plant growth-promoting,and can be used as seedling substrate.