【摘要】 应用Ｔｎ５转座子对粪产碱菌野生型菌株Ａ１５０１进行诱变处理，用荧光增白剂及ＴＴＣ为标记筛选，分别获得胞外多糖缺陷型和丰富型突变株。激光共聚焦观察证实，ＥＰＳ突变株确实具有与野生型不同的表面特性，贴根试验表明，突变株贴根菌数均少于野生型，胞外多糖生成过多或过少均影响菌体与根表的有效结合更多还原

【Abstract】 Using Tn5-mutagenesis, the Alcaligenes faecalis mutants showing reduced (A1531)andincreased (A1532)synthesis of EPS were isolated. A1531 synthesized 61%of EPS, while the A1532 syn-thesized 201%of EPS in comparison with the wild type (A1501). The difference of cell surface of A. fae-calis and its mutants were observed using Laser Confocal Micrographs (LCM).The attachment of associa-tive diazotroph A. faecalis and its mutants A1531 and A 1532 to intact rice plants was examined. EPS-(A1531)and EPS￣++(A1532)mutants were only defective in anchoring. The results indicated the EPSplay rather important role in the association between host plant and bacteria.更多还原