为获得植物内生促生菌资源,本文从桑树(Morus alba L.)叶片中分离筛选促生细菌,进行分类鉴定,检测其促生特性,探讨其对小麦(Triticum aestivum L.)的促生机制。结果显示,常规平板法从四个桑树品种叶片中分离出13株内生细菌,其中品种970...为获得植物内生促生菌资源,本文从桑树(Morus alba L.)叶片中分离筛选促生细菌,进行分类鉴定,检测其促生特性,探讨其对小麦(Triticum aestivum L.)的促生机制。结果显示,常规平板法从四个桑树品种叶片中分离出13株内生细菌,其中品种9703中分离的编号AG-2菌株表现出良好的促生效果。结合形态学和16S rRNA序列分析鉴定菌株AG-2为多黏类芽孢杆菌(Paenibacillus polymyxa)。平板定性法和高效液相色谱–串联质谱法(HPLC-MS/MS)分析表明菌株AG-2具有产有机酸、蛋白酶、纤维素酶、铁载体以及吲哚乙酸(IAA)、异戊烯基腺嘌呤(IP)和异戊烯基腺嘌呤核苷(IPA)的促生特性。室内幼苗浇灌试验结果表明,与对照组相比,菌株AG-2处理小麦幼苗12 d后,苗鲜重、根鲜重和单株总鲜重显著增加(P P P P In order to obtain endophytic bacteria to promote plants growth, strains were isolated and screened from mulberry leaves. Based on identification of the strain and analysis of the growth-promoting characteristics, the growth-promoting mechanism on wheat was explored. Results showed that 13 endophytic bacteria were isolated from the leaves of four mulberry varieties using conventional plate method, in which strain AG-2 from variety 9703 showed excellent growth-promoting effects. Through morphology and 16S rRNA sequence analysis, strain AG-2 was identified as Paenibacillus polymyxa. Plate qualitative analysis and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis showed that strain AG-2 had the promoting properties of producing organic acid, protease, cellulase, siderophore, as well as indole-3-acetic acid (IAA), isopentenyladenine (IP), and isopentenyladenine nucleoside (IPA). Compared with the control group, after 12 days of irrigating wheat seedlings in greenhouse, shoot fresh weight, root fresh weight and total fresh weight per plant significantly increased (P P P P < 0.05), with the increase of 113.14%, 17.68%, and 68.24% compared to the control group, respectively. Above results indicated that strain AG-2 could effectively promote the growth of wheat seedlings and had the potential to be developed into agricultural microbial strain.展开更多
文摘为获得植物内生促生菌资源,本文从桑树(Morus alba L.)叶片中分离筛选促生细菌,进行分类鉴定,检测其促生特性,探讨其对小麦(Triticum aestivum L.)的促生机制。结果显示,常规平板法从四个桑树品种叶片中分离出13株内生细菌,其中品种9703中分离的编号AG-2菌株表现出良好的促生效果。结合形态学和16S rRNA序列分析鉴定菌株AG-2为多黏类芽孢杆菌(Paenibacillus polymyxa)。平板定性法和高效液相色谱–串联质谱法(HPLC-MS/MS)分析表明菌株AG-2具有产有机酸、蛋白酶、纤维素酶、铁载体以及吲哚乙酸(IAA)、异戊烯基腺嘌呤(IP)和异戊烯基腺嘌呤核苷(IPA)的促生特性。室内幼苗浇灌试验结果表明,与对照组相比,菌株AG-2处理小麦幼苗12 d后,苗鲜重、根鲜重和单株总鲜重显著增加(P P P P In order to obtain endophytic bacteria to promote plants growth, strains were isolated and screened from mulberry leaves. Based on identification of the strain and analysis of the growth-promoting characteristics, the growth-promoting mechanism on wheat was explored. Results showed that 13 endophytic bacteria were isolated from the leaves of four mulberry varieties using conventional plate method, in which strain AG-2 from variety 9703 showed excellent growth-promoting effects. Through morphology and 16S rRNA sequence analysis, strain AG-2 was identified as Paenibacillus polymyxa. Plate qualitative analysis and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis showed that strain AG-2 had the promoting properties of producing organic acid, protease, cellulase, siderophore, as well as indole-3-acetic acid (IAA), isopentenyladenine (IP), and isopentenyladenine nucleoside (IPA). Compared with the control group, after 12 days of irrigating wheat seedlings in greenhouse, shoot fresh weight, root fresh weight and total fresh weight per plant significantly increased (P P P P < 0.05), with the increase of 113.14%, 17.68%, and 68.24% compared to the control group, respectively. Above results indicated that strain AG-2 could effectively promote the growth of wheat seedlings and had the potential to be developed into agricultural microbial strain.
