【摘要】 土壤盐碱化是影响全球农业生产的主要非生物胁迫之一。在我国，盐碱化土壤分布广泛，严重限制了作物的产量和质量。棉花作为我国重要的经济作物，不仅在纺织工业中占有重要地位，其油脂和蛋白质也是重要的食品和工业原料。然而，土壤盐碱化导致的渗透压增加、营养元素缺乏以及土壤结构破坏等问题，严重制约了其生长和发育。为了应对这一挑战，本研究旨在筛选和利用棉花根际高抗盐碱芽孢杆菌，改善土壤理化性质，进而提升盐碱地棉花抗性和产量。研究团队从棉花根际土壤中分离出具有抗盐碱特性的菌株，并通过逐步提高培养介质的盐碱度，筛选出两株具有多功能的高抗盐碱芽孢杆菌A3-3和N-7。菌株A3-3能在15%NaCl和pH 9.0的高盐碱条件下生长，具备溶解无机磷、分解有机磷、溶解钾、产生蛋白酶、产生纤维素酶以及拮抗棉花枯萎病菌的功能，初步鉴定该菌株为耐盐芽孢杆菌（Bacillus halotolerans）。菌株N-7能在15%NaCl和pH 11.0的高盐碱条件下生长，并表现出类似菌株A3-3的功能，初步鉴定为海内氏芽孢杆菌（Bacillus haynesii）。盆栽试验结果表明，菌株A3-3和N-7对棉花植株在中重度盐碱条件下的生长具有显著的促进作用。菌株A3-3和N-7在棉花专用型抗盐碱菌剂的研发和应用上展现出巨大潜力，为盐碱化土壤的生物修复和棉花的可持续生产提供了新的策略。更多还原

【Abstract】 Soil salinization is one of the major abiotic stresses affecting global agricultural production. In China, widespread saline-alkali soils severely restrict crop yield and quality. Cotton, as an important economic crop in China, holds a significant position in the textile industry, and its oil and protein are also vital food and industrial raw materials. However, increased osmotic pressure, nutrient deficiency, and soil structure disruption caused by soil salinization severely limit cotton growth and development. To address this challenge, this study aims to improve the physicochemical properties of saline-alkali soils and thereby enhance the resistance and yield of cotton in saline-alkali lands through screening and utilizing Bacillus strains with high salt-alkali resistance from cotton rhizosphere. Our research team isolates strains with saline-alkali resistance from cotton rhizosphere soil and selects two multifunctional, highly saline-alkali-resistant Bacillus strains A3-3 and N-7 through progressive salinity-alkalinity acclimation. Strain A3-3 can grow under high saline-alkali conditions of 15% NaCl and pH 9.0, and possesses various bioactivities, including inorganic phosphorus solubilization, organic phosphorus decomposition,potassium solubilization, protease production, cellulase production, and antagonism against cotton wilt disease, preliminarily identified as Bacillus halotolerans. Strain N-7 can grow under high saline-alkali conditions of 15% NaCl and pH 11.0, and exhibits similar functions as strain A3-3, preliminarily identified as Bacillus haynesii. Pot experiments show that both strains significantly promote cotton growth under moderate to severe saline-alkali stress. Therefore, Strains A3-3 and N-7 have great potential in the development and application of cotton-specific saline-alkali-resistant microbial agents, providing new strategies for bioremediation of saline-alkali soils and sustainable cotton production.更多还原