Crop Protection Division, ICAR-National Rice Research Institute, Cuttack, 753006, India; Department of Botany, Utkal University, Bhubaneswar, India.
Crop Protection Division, ICAR-National Rice Research Institute, Cuttack, 753006, India.
Microb Pathog. 2024 Dec;197:106966. doi: 10.1016/j.micpath.2024.106966. Epub 2024 Sep 19.
Utilizing beneficial microorganisms associated with plants, particularly endophytes, is becoming more and more prevalent since it supports the physiological health and evolutionary adaption of the host. The range of enhanced endophytic bacteria found in wild rice makes it a promising resource for sustainable agriculture. Current study focused on benefits of bacterial endophytes isolated from tissues of wild rice plants' roots, stems, and leaves for managing the health and development of rice (Oryza sativa L.) plants. Bacterial endophytes were characterized using 16 S rRNA. Treatments with Priestia megaterium (NRRI EB 1) and Priestia aryabhattai (NRRI EB 2) outperformed the other isolates in rice growth enhancement activities significantly. The biocontrol efficacy of bacterial endophytes was tested against Xanthomonas oryzae pv. oryzae and Rhizoctonia solani and percentage of inhibition was higher in NRRI EB 1 by 79.32-80.83 % and in NRRI EB 2 by 79.69-80.45 %. Bio-priming the seeds with specific endophytic bacterial strains led to a decrease in average germination time, an increase in seedling vigor, and total chlorophyll content. Additionally, they generated greater amounts of soluble phosphate (40.91-83.70 μg/mL) and indole acetic acid (28.10-60.18 μg/mL), which are in the midst of encouraging more plant development. Higher expressions of defense enzymes in comparison to the control, including catalase (>220 % in root and shoot), peroxidase (>200 % in shoot and root), and superoxide dismutase (>150 % in shoot and root) illustrates the rice crop's resilience to withstand stress. The activity of the mentioned enzymes was further validated through the activation of corresponding defense genes such as DEFENSIN (>2-fold), PAL (>3-fold), PR-3 (>2-fold), POX (>2-fold) and LOX (>1-fold) in relation to the untreated plants. The possibility exists to extract advantageous endophytic bacteria from wild rice species, potentially rewilding the microbiome of cultivated rice cultivars and fostering their deployment.
利用与植物（特别是内生菌）相关的有益微生物，越来越受到重视，因为它支持宿主的生理健康和进化适应。从野生稻中发现的增强型内生细菌种类繁多，这使其成为可持续农业的有前途的资源。本研究主要关注从野生稻植物根、茎和叶组织中分离的细菌内生菌对管理水稻（Oryza sativa L.）植物健康和发育的益处。使用 16S rRNA 对内生细菌进行了特征描述。与其他分离株相比，Priestia megaterium（NRRI EB 1）和 Priestia aryabhattai（NRRI EB 2）在促进水稻生长方面的表现明显更好。内生细菌的生物防治效果针对 Xanthomonas oryzae pv. oryzae 和 Rhizoctonia solani 进行了测试，NRRI EB 1 的抑制率为 79.32-80.83%，NRRI EB 2 的抑制率为 79.69-80.45%。通过特定的内生细菌菌株对种子进行生物引发处理，可减少平均发芽时间，提高幼苗活力和总叶绿素含量。此外，它们还产生了更多的可溶性磷酸盐（40.91-83.70μg/mL）和吲哚乙酸（28.10-60.18μg/mL），这有助于促进更多的植物发育。与对照相比，防御酶的表达更高，包括过氧化氢酶（根和茎中超过 220%）、过氧化物酶（根和茎中超过 200%）和超氧化物歧化酶（根和茎中超过 150%），这表明水稻作物具有抵御压力的弹性。通过激活未处理植物中相应的防御基因，如 DEFENSIN（超过 2 倍）、PAL（超过 3 倍）、PR-3（超过 2 倍）、POX（超过 2 倍）和 LOX（超过 1 倍），进一步验证了这些酶的活性。有可能从野生稻种中提取有益的内生细菌，潜在地重新野化栽培稻品种的微生物组并促进其应用。
