Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India.
Department of Agricultural Microbiology, Agricultural College and Research Institute, Madurai, Tamil Nadu, India.
J Appl Microbiol. 2021 Nov;131(5):2448-2465. doi: 10.1111/jam.15112. Epub 2021 May 11.
This study aimed at determining the distribution, colonization and growth promoting nature of Methylobacterium spp. in tissue culture banana plantlets.
Leaf samples from different field grown banana cultivars were used for Methylobacterium spp., isolation. Metabolic profile and functional characterization for plant growth-promoting traits of the isolates were assessed. The isolates were confirmed using 16S rRNA gene sequencing analysis, which resulted in six distinct species of Methylobacterium namely M. radiotolerans, M. salsuginis, M. thiocyanatum, M. rhodesianum, M. rhodinum and M. populi. Methylobacterium spp. inoculation experiment was conducted under hydroponic system in tissue culture banana plantlets (germ free) with eight selected isolates. A significant increase in growth parameters of Methylobacterium treated plantlets compared to uninoculated control was observed. Methylobacterium salsuginis TNMB03-gfp29 was developed and colonization micrograph was obtained using confocal laser scanning microscopy (CLSM) and scanning electron microscopy in different parts of banana plantlets (root, stem and leaves).
Field grown banana plants found to harbour diverse endophytic Methylobacterium population. Our finding suggests that endophytic Methylobacterium species may provide significant plant growth promoting compounds/nutrients to the banana plants. The experimental results demonstrated the efficacy of Methylobacterium spp. as a potential bioinoculant and can be exploited as a phyllosphere and rhizosphere based bioinoculant for the initial establishment and growth of tissue culture banana plantlets.
This study extended our knowledge on the distribution of Methylobacterium spp. in banana plants and endophytic colonization nature of this particular genus in plants. In addition, efficient isolate (M. salsuginis TNMB03) identified in this study may be promoted as bio-inoculants for banana plants after field evaluation.
本研究旨在确定甲基杆菌属（Methylobacterium spp.）在组织培养香蕉苗中的分布、定殖和促生长特性。
从不同田间生长的香蕉品种叶片中分离甲基杆菌属。评估了分离株的代谢谱和促进植物生长的功能特征。通过 16S rRNA 基因测序分析鉴定分离株，结果确定了 6 种不同的甲基杆菌属，即甲基杆菌（M. radiotolerans）、甲基杆菌（M. salsuginis）、甲基杆菌（M. thiocyanatum）、甲基杆菌（M. rhodesianum）、甲基杆菌（M. rhodinum）和甲基杆菌（M. populi）。在组织培养香蕉苗（无菌）的水培系统中进行了甲基杆菌属接种实验，使用了 8 个选定的分离株。与未接种对照相比，接种甲基杆菌属的植物苗的生长参数显著增加。开发了甲基杆菌（M. salsuginis）TNMB03-gfp29 并使用共聚焦激光扫描显微镜（CLSM）和扫描电子显微镜在香蕉苗的不同部位（根、茎和叶）获得了定植微观图像。
田间生长的香蕉植物被发现含有多样化的内生甲基杆菌属种群。我们的发现表明，内生甲基杆菌属物种可能为香蕉植物提供重要的植物生长促进化合物/养分。实验结果表明，甲基杆菌属作为一种潜在的生物接种剂具有功效，可以作为一种叶际和根际的生物接种剂，用于组织培养香蕉苗的初始建立和生长。
本研究扩展了我们对香蕉植物中甲基杆菌属分布的了解，以及该属在植物中的内生定殖特性。此外，本研究中鉴定的有效分离株（M. salsuginis TNMB03）可能在田间评估后被推广为香蕉植物的生物接种剂。
