土壤微生物介导植物抗盐性机理的研究进展

土壤盐渍化是农业可持续生产面临的严重威胁之一。利用高效、低成本和适应性强的方法对盐渍区进行修复是一个具有挑战性的目标。土壤微生物在调节植物根际环境、调控生长发育和提高系统生产力等方面具有重要作用。近年来,由微生物驱动的植物胁迫耐受性受到了广泛关注。通过识别和利用能与植物相互作用的土壤微生物来减轻盐胁迫,为盐渍区改良提供了一种新策略,也为与胁迫耐受相关新机制的发现开辟了新途径。了解不同微生物介导的胁迫耐受性的潜在生理机制对有效利用这些微生物促进农业可持续生产至关重要,本文从植物养分吸收、渗透平衡、激素水平、抗氧化功能等方面论述了国内外关于土壤微生物介导植物耐盐性的作用机理,评估了目前关于土壤微生物参与调节植物耐盐性相关研究的有益作用和不足之处,提出了未来研究的发展方向。目前通过提高养分及水分吸收效率维持盐胁迫下植物离子稳态,提高生长素的合成、降低乙烯的释放调控植物激素水平是土壤微生物改良植物耐盐性的目标过程,然而单个外源微生物接种时会与土著微生物组竞争,导致许多微生物菌株不能在土壤或植物根系中定殖或存活,致使微生物在大规模农业生产应用中仅取得了有限的成功。未来微生物介导植物抗盐性的研究应突破单一微生物接种的研究方式,进一步在群落水平上阐明植物-微生物的相互作用介导植物抗盐性的机制,解决农业微生物利用的关键问题。

Research Progress of Soil Microbial Mechanisms in Mediating Plant Salt Resistance

Soil salinization has seriously hindered the sustainable agricultural production. Remediation of salt affected areas with efficient, low cost and adaptable method is a challenging goal for scientists. Soil microorganisms play important roles in regulating rhizosphere environment of plants, enhancing plant development and productivity. Adaptation of plants to stress driven by soil microbes has been attracted extensive attention. The identification and exploitation of soil microorganisms that interact with plants in alleviating salt stress provides a new strategy for the improvement of saline area, as well as new approaches to discover mechanisms involved in stress tolerance. Knowledge of the underlying physiological mechanisms by which diverse microbes mediate stress tolerance, is critical to the effective use of these microbes to assure sustained agricultural production. This paper reviewed the recent studies about the mechanisms of soil microorganisms mediated in plant salt stress tolerance from the aspects of plant nutrient absorption, osmosis balance, hormone levels and antioxidant function. The beneficial effects and lack of current researches related to soil microorganism in the regulation of plant salt tolerance were evaluated, and the directions of the future research were also proposed. At present, improving nutrient and water uptake efficiency to maintain plant ion homeostasis under salt stress, increasing auxin synthesis and reducing ethylene release to regulate plant hormone levels seem to be promising target processes for soil biota-improved plant salt tolerance. However, limited success has been obtained in application of microorganism to large-scale agricultural production, due to the competition of introduced single microbial strains with native soil microbial communities which resulted in many bacterial strains has little colonization efficiency. The researches related to microbial mediated plant salinity tolerance should break through the single microbial inoculation, further clarify the mechanism of plant-microbial interaction at the community level, and solve the key problems of microbial utilization in agricultural production.