棉花解盐促生菌的筛选及其作用机理的初步研究

采用平板稀释法从盐碱环境植物根围土样中分离得到263株细菌,从中筛选出15株在盐胁迫下对棉种的发芽率和胚根生长有促进作用的菌株,而且对不同浓度的氯化钠有一定的耐受性.其中Rs15-4菌株效果显著,发芽率提高了11.8%,平均根长和茎长分别提高了27.33%和17.77%,平均单株鲜重和干重提高了14.92%和7.2%.同时对Rs15-4菌株的作用机理进行了初步研究,结果发现：通过菌株处理后棉花子叶细胞膜透性比对照减小26.15%,在一定程度上促进了根系对N、P、K元素的吸收.

Preliminary Study on Action Mechanism and Isolation of Strains for Relieving-salt-stress and Promoting Growth of Cotton

263 strains of plant rhizobacteria were isolated with the plate dilution in selected media containing the given concentration of NaCl, and 15 strains of that which could increase the germinating rate, promote growth of cotton, and tolerate stress of the different concentrations of NaCI. The effect of Rs15-4 strain on the germinating rate and promoting growth of cotton were investigated. The results showed that the germinating rate of cotton with treatment with Rs15-4 strain enhanced 11.8% .The average root and stem length of cotton increased 27.33% and 17.7%, respectively.The average fresh weight and dry weight of cotton increased 14.92% and 7.2% respectively. At the same time, the action mechanism of Rs15-4 strain to cotton was studied. It indicated that the cell membrane permeability of cotton treatment by Rs15-4 strain was of 26.15% lower than that of cotton without treatment by Rs15-4 strain. The absorption of N,P and K in cotton cell was promoted after treatment with Rs15-4 and the absorption of Na was significantly decreased.