辣椒根际促生菌的分离筛选及生物育苗基质研制.

[Objectives] The paper aimed at combining plant growth-promoting rhizobacteria (PGPR) with ordinary nursery substrates to develop bio-nursery substrates which can effectively promote rhizosphere colonization and plant growth abilities of the strains. [Methods] Indole acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase production abilities were employed to isolate pepper rhizosphere functional strains. Comparation on the seedling culture effects from bio-nursery substrates produced by these strains and the subsequently growth characters for these seedlings after transplanting were used to screen the most efficient strain. [Results] Six strains which produced more than 5 mg·L-1of IAA were first screened,and 3 strains among which including strain NJAU-G10, NJAU-N5 and NJAU-N1 possessed stronger ACC deaminase activity. Two seasons seeding cultivation experiments showed that the functional strain NJAU-G10 with the best addition amount of 5% in the bio-nursery substrate showed the best root colonization and growth promotion abilities compared to the other strains. Pot experiments showed that the seeding cultured from bio-nursery substrate produced by strain NJAU-G10 had significantly best growth characters and the functional strain effectively colonized on the pepper root after transplanting. Finally, based on the phylogenetic analysis of 16S rDNA and morphological and biochemical characteristics, strain NJAU-G10 was identified as Bacillus subtilis. [Conclusions] One PGPR strain, Bacillus subtilis NJAU-G10, which had growth-promoting and root colonization abilities in bio-nursery substrate,was isolated in this study. Results could provide the theoretical and technical support for exploring the novel PGPR products. [ABSTRACT FROM AUTHOR]

[目的]将根际促生菌(plant growth-promoting rhizobacteria,PGPR)与普通育苗基质联合,研制成生物育苗基质,进而促进功能菌株苗期的根际定殖和移苗后促生功能的发挥.[方法]利用从辣椒根际分离筛选的产IAA和ACC脱氨酶菌株,保活添加至普通育苗基质研制成生物育苗基质,通过比较育苗效果筛选出生物育苗基质的最佳配伍菌株.[结果]从辣椒根际分离获得6株IAA产生量大于5 mg·L-1的菌株,其中菌株NJAU-G10、NJAU-N5和NJAU-N1同时能产ACC脱氨酶,且能力高于其他菌株;两季苗盘育苗试验结果表明,添加菌株NJAU-G10的生物基质,表现出较其他菌株更为突出的根际定殖和促进幼苗生长的能力,并确定其最佳接种量为5%;盆栽试验结果表明,菌株NJAU-G10在移苗后对辣椒的生长仍具有显著的促进作用,且能够有效地在根际定殖;结合形态、生理生化特征和16S rDNA基因序列分析,初步鉴定菌株NJAU-G10为枯草芽孢杆菌.[结论]分离获得一株枯草芽孢杆菌NJAU-G10,添加其研制的生物育苗基质能够有效促进辣椒苗盘期种苗及其移栽后的生长,研究结果能够为含PGPR蔬菜育苗基质的开发提供理论支撑,同时为PGPR新产品的开发提供新的思路. [ABSTRACT FROM AUTHOR]