Improvement of nitrogen-fixing ability and survivability of nitrogen fixers in the rhizoshere of rice.

提高水稻根际固氮能力和固氮剂生存能力。

• 批准号: 12460048
• 负责人: UOZUMI Takeshi
• 金额: $ 8.96万
• 依托单位: Meiji University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12460048/
• 关键词: Nitrogen-fixing bacteria; Paenibacillus; Pantoea; Klebsiella; Oryza sativa; Miscanthus sinensis; Gramineae; Antibiotic; 生育促進; 根圏; 接種効果; nitrogen fixation; rice; 窒素固定; イネ根圏; 窒素肥料; バクテリオシン; ピオシアニン; Azospirillum

To obtain nitrogen-fixing bacteria with a high survivability in the rhizosphere of rice, bacteria were isolated from roots and rhizosphere soils of graminaceous plants, using N-free media. Among 4 Gram-negative facultatively anaerobic bacterial strains, 3 strains were identified as Klebsiella pneumoniae by API20 test. One strain (E-1030)was judged to be Pantoea sp. Strain E1030 had a broad spectrum antibiotic activity, but the activity was lost during culture preservation. Two motile, spore-forming and facultatively anaerobic bacterial strains were isolated, and they were identified to be Paenibacillus sp. by physiological properties and 16S rDNA sequence. As the sequence homologies were 96〜97% to the nearest Paenibacillus species, they were judged to be new species, and named Paenibacillus fujiensis sp. nov. Br1 (DDBJ Accesion No.AB092351, Taxonomy ID 208550), and Paenibacillus abekawaensis sp. nov. MG1 (DDBJ Accession No.AB119649, Taxonomy ID 244733), respectively.Nitrogen-fixing ability of P. fujiensis Br1 was 7〜15 times as large as those of commonly used Klebsiella, Azospirillum and Herbaspirillum strains. Inoculation test to rice plant aseptically cultured on an N-free medium in a glass cylinder showed that strain Br1 had greater growth promoting effects than Klebsiella pneumoniae M5a1 and Azospirillum lipoferum COC8, in terms of length and/or dry weight.

为了获得在水稻根际具有较高存活率的固氮细菌，采用无氮培养基从禾本科植物根际土壤和根际土壤中分离细菌。4株革兰氏阴性兼性厌氧菌中，API20检测3株为肺炎克雷伯菌。其中1株菌株E-1030为Pantoea sp.菌株，菌株E1030具有广谱抗菌活性，但在培养保存过程中活性丧失。分离得到两株运动性、产孢性和兼性厌氧菌株，经生理特性和16S rDNA序列鉴定为Paenibacillus sp.。由于序列与最接近的芽孢杆菌种同源性为96 ~ 97%，判定为新种，并命名为芽孢杆菌fujiensis sp. nov. Br1 （DDBJ加入号）。AB092351，分类号208550)和阿贝卡瓦芽孢杆菌sp. 11 . MG1 (DDBJ登记号：AB119649，分类号244733)。福建P. fujiensis Br1的固氮能力是常用的克雷伯菌、偶氮螺旋菌和Herbaspirillum菌株的7 ~ 15倍。在玻璃筒无氮培养基上无菌培养水稻植株的接种试验表明，菌株Br1在长度和（或）干重方面均比肺炎克雷伯菌M5a1和脂质偶氮螺旋菌COC8具有更强的促生长作用。