摘要
从甜罗勒(Ocimum basilicum)根际分离得到的28株细菌菌株,通过平板对峙试验筛选出对烟草赤星病菌(Alternaria alternata)抑制作用最强的菌株LL-16,其平均抑菌带宽度为7.77 mm。对LL-16菌株进行生理生化鉴定和16S r DNA序列分析,表明其与Bacillus subtilis(JQ978219)聚类成为一支,支持强度达到71%,同源性为98.9%,鉴定其属于枯草芽孢杆菌(Bacillus subtilis)。采用菌落直径法和凹玻片法测定不同浓度的菌液、无菌滤液和灭活滤液对烟草赤星病菌的菌丝生长和孢子萌发的影响。结果表明,一定浓度范围内,菌液、无菌滤液和灭活滤液均能抑制赤星病菌丝生长和孢子芽管伸长,形成泡状芽管,致使病菌丧失侵染能力。同一种处理随着其浓度的降低对赤星病菌的抑制作用减弱。相同浓度的3种处理抑制作用从强到弱依次为菌液、无菌滤液、灭活滤液。
28 rhizospeheric bacterial strains were obtained from sweet Ocimum basilicum roots, strain LL-16 was screened to have the strongest inhibition against tobacco brown spot through dual culture on PDA plates. The average antibacterial width was 7.77mm. Analysis on 16S rDNA sequence and physiological and biochemical characteristics of strain LL-16,showed that Bacillus subtilis （JQ978219） clustering and strain LL-16 became a branch, support strength reached 71% and the homology was 98.9%.SO, it was identified as Bacillus subtilis. Through diameter of the colony and the concave slide method, the effects on tobacco brown spot mycelial growth and spore germination of bacteria liquid, bacteria free filtrate and inactivated filtrate in different concentrations were determined. The results showed that in a certain range of concentration bacteria liquid, bacteria free fihrate and inactivated filtrate inhibited tobacco brown spot mycelial growth and spore germination strongly, resulting the formation of bubble germ tube and in loss of ability of pathogen infection. The same treatment as the concentration decreasing, the inhibition effects on Ahernaria alternate weakened. Three treatments of the same concentration, the inhibition effects performed as： bacteria liquid 〉 bacteria free filtrate 〉inactivated filtrate.
出处
《湖北农业科学》
2015年第8期1886-1891,共6页
Hubei Agricultural Sciences
基金
云南省烟草公司科技项目(2011YN58)
作者简介
张芬芬（1990-），女，湖南郴州人，在读硕士研究生，研究方向为烟草生理生化，（电话）15825252051（电子信箱）742938495@qq．com
通信作者，赵明富（1975-）男，副教授，主要从事微生物学研究，（电子信箱）zhaomintgfu@163．com。
通信作者，文国松（1969-），男，副研究员，主要从事分子生物学和微生物学技术研究，（电子信箱）wengs@163．com；
