【摘要】 植物根际促生菌(PGPR)具有促进植物生长和提高重金属吸收的能力。因此,将PGPR作为土壤修复菌接种到具有较大生物量的植物根际,对提高植物修复效率具有重要意义。从镉污染地区的植物根际土壤中分离得到30株耐镉菌株,根据其分泌吲哚乙酸(IAA)、溶磷、产1-氨基环丙烷-1-羧酸(ACC)脱氨酶、铁载体及促生试验结果,选取2株具有PGPR特性的菌株接种到耐镉性不同的两种一年生黑麦草品种IdyⅡ和Wasehope中,测定它们对黑麦草生长和镉吸收积累的影响。当土壤镉含量为(19.5±0.42)mg·kg-1时,分别接种Pi01和Ma02,结果表明:镉处理下,接种2种菌株后两种一年生黑麦草的生物量和镉积累量均显著提高(P<0.05);叶绿素含量增加;光合作用增强;根际土壤镉有效态含量增加。因此,接种筛选出的2种PGPR能够促进黑麦草生长,增加其对镉的积累。更多还原

【Abstract】 Some plant growth-promoting rhizobacteria(PGPR)have the ability to promote plant growth and increase heavy metal absorption. Therefore,there is an opportunity to improve the efficiency of phytoremediation by inoculating the rhizosphere of plants which accumulate a large biomass with relevant strains of bacteria. In this study,30 cadmium(Cd)-tolerant PGPR strains were isolated from soil of the plant rhizosphere in cadmium-contaminated areas. Based on the results of indole-3-acetic acid secretion,phosphorus dissolution,1-aminocyclopropane-1-carboxylate deaminase production,iron carrier and growth promotion experiments,two PGPR strains designated Pi01 and Ma02 were selected and inoculated onto two cultivars of annual ryegrass with contrasting cadmium tolerance,Idy Ⅱ and Wasehope,and the effects on the growth and cadmium accumulation of ryegrass were measured. A pot culture test was carried out using soil contaminated with Cd at a concentration of(19. 5±0. 42)mg·kg-1,and the two PGPR strains,Pi01 and Ma02,were inoculated onto the two cultivars of annual ryegrass.The biomass and Cd accumulation of both ryegrasses were significantly increased by inoculation with Pi01 and Ma02. In addition, inoculation with PGPR increased chlorophyll content, photosynthetic parameters, and extractable Cd concentration in the rhizosphere. Therefore,the two selected PGPRs,Pi01 and Ma02,can promote the growth of annual ryegrass and increase its accumulation of cadmium.更多还原