Dutta Swarnalee, Choi Soo Yeon, Lee Yong Hoon
Division of Biotechnology, Jeonbuk National University, Jeonju, South Korea.
Crop Foundation Research Division, National Institute of Crop Science, Wanju-gun, South Korea.
Front Microbiol. 2022 Jul 22;13:877781. doi: 10.3389/fmicb.2022.877781. eCollection 2022.
Seed endophytes are of interest because they are believed to affect seed quality, and ultimately, plant growth and fitness. A comprehensive understanding of the assembly of the seed microbiome during seed development and maturation, the fate of microbes during storage, and the migration of microbes during seedling growth are still lacking. In this study, to understand the assembly and fate of endogenous bacteria in rice seeds from the ripening stage to the storage and seedling stages, we employed culture-dependent and metagenomic analyses. Bacterial communities in rice seeds were composed of a few dominant taxa that were introduced at the milky and dough stages, and they persisted during seed maturation. The culturable bacterial population gradually increased during the ripening stage, whereas there was a gradual decrease during storage. Bacteria that persisted during storage proliferated after imbibition and were distributed and established in the shoots and roots of rice seedlings. The storage temperature influenced the abundance of bacteria, which consequently changed the bacterial composition in the shoots and roots of seedlings. , and were consistently abundant from seed development to the germination stage. Some endogenous bacterial strains significantly promoted the growth of and rice plants. Overall, our results indicate that rice seeds are colonized by a few bacterial taxa during seed development, and their relative abundance fluctuates during storage and contributes significantly to the establishment of endophytes in the stems and roots of rice plants. The selected bacterial isolates can be used to improve the growth and health of rice plants. To the best of our knowledge, this is the first study to reveal the dynamics of bacterial populations during storage of rice seeds at different temperatures. The temporal dynamics of the bacterial community during seed storage provide clues for the manipulation of endogenous bacteria in rice plants.
种子内生菌备受关注，因为人们认为它们会影响种子质量，最终影响植物的生长和适应性。目前仍缺乏对种子发育和成熟过程中种子微生物组组装、储存期间微生物的命运以及幼苗生长期间微生物迁移的全面了解。在本研究中，为了解水稻种子从成熟阶段到储存和幼苗阶段内生细菌的组装和命运，我们采用了基于培养的分析方法和宏基因组分析。水稻种子中的细菌群落由少数在乳熟期和面团期引入的优势类群组成，它们在种子成熟过程中持续存在。可培养细菌种群在成熟阶段逐渐增加，而在储存期间逐渐减少。在储存期间持续存在的细菌在吸水后增殖，并分布并定殖于水稻幼苗的地上部分和根部。储存温度影响细菌丰度，从而改变幼苗地上部分和根部的细菌组成。从种子发育到发芽阶段始终丰富。一些内生细菌菌株显著促进了 和水稻植株的生长。总体而言，我们的结果表明，水稻种子在发育过程中被少数细菌类群定殖，它们的相对丰度在储存期间波动，并对水稻植株茎和根中内生菌的建立有显著贡献。所选的细菌分离物可用于改善水稻植株的生长和健康状况。据我们所知，这是第一项揭示不同温度下水稻种子储存期间细菌种群动态变化的研究。种子储存期间细菌群落的时间动态变化为调控水稻植株内生细菌提供了线索。
