School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China; Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
College of Agriculture, Northeast Agricultural University, Changjiang Road 600, Harbin 150030, China.
Microbiol Res. 2024 Nov;288:127886. doi: 10.1016/j.micres.2024.127886. Epub 2024 Aug 31.
Rhizobia interact with leguminous plants in the soil to form nitrogen fixing nodules in which rhizobia and plant cells coexist. Although there are emerging studies on rhizobium-associated nitrogen fixation in cereals, the legume-rhizobium interaction is more well-studied and usually serves as the model to study rhizobium-mediated nitrogen fixation in plants. Rhizobia play a crucial role in the nitrogen cycle in many ecosystems. However, rhizobia are highly sensitive to variations in soil conditions and physicochemical properties (i.e. moisture, temperature, salinity, pH, and oxygen availability). Such variations directly caused by global climate change are challenging the adaptive capabilities of rhizobia in both natural and agricultural environments. Although a few studies have identified rhizobial genes that confer adaptation to different environmental conditions, the genetic basis of rhizobial stress tolerance remains poorly understood. In this review, we highlight the importance of improving the survival of rhizobia in soil to enhance their symbiosis with plants, which can increase crop yields and facilitate the establishment of sustainable agricultural systems. To achieve this goal, we summarize the key challenges imposed by global climate change on rhizobium-plant symbiosis and collate current knowledge of stress tolerance-related genes and pathways in rhizobia. And finally, we present the latest genetic engineering approaches, such as synthetic biology, implemented to improve the adaptability of rhizobia to changing environmental conditions.
根瘤菌与土壤中的豆科植物相互作用，形成固氮根瘤，其中根瘤菌和植物细胞共存。尽管关于谷物中根瘤菌相关固氮的新兴研究不断涌现，但豆科植物-根瘤菌的相互作用研究得更为透彻，通常被用作研究植物中根瘤菌介导固氮的模型。根瘤菌在许多生态系统的氮循环中起着至关重要的作用。然而，根瘤菌对土壤条件和物理化学性质（如水分、温度、盐分、pH 值和氧气供应）的变化非常敏感。全球气候变化直接导致的这些变化正在挑战根瘤菌在自然和农业环境中的适应能力。尽管有一些研究已经确定了赋予根瘤菌适应不同环境条件的基因，但根瘤菌应激耐受的遗传基础仍知之甚少。在这篇综述中，我们强调了提高根瘤菌在土壤中生存能力的重要性，以增强其与植物的共生关系，从而提高作物产量并促进可持续农业系统的建立。为了实现这一目标，我们总结了全球气候变化对根瘤菌-植物共生关系的关键挑战，并整理了目前关于根瘤菌应激耐受相关基因和途径的知识。最后，我们介绍了最新的遗传工程方法，如合成生物学，用于提高根瘤菌对环境变化的适应能力。
