两株生防菌对烟草黑胫病的抑制活性及其鉴定.pdf

两株生防菌对烟草黑胫病的抑制活性及其鉴定 王晶晶，蒋士君，常淑娴，王拥军，申顺善 河南农业大学植物保护学院，郑州市文化路 95 号 450002 摘 要: 为测定烟草黑胫病生防菌 K9-3 和 L14-2 两菌株的生防潜力，通过对峙培养法、孢子萌发试验和盆栽试验测定对烟草黑胫 病病原菌的抑制能力，以双层滤纸法和盆栽检测法测定在烟草根际定殖能力，并根据形态特征、生理生化特性和 16S rDNA 序列分 析，鉴定 K9-3 和 L14-2 两株生防菌。结果表明: 在室内试验中，这两株生防菌可抑制烟草黑胫病病原菌菌丝的生长、游动孢子囊的 形成、游动孢子的释放和休止孢子的萌发; 在盆栽试验中，有效防治烟草黑胫病，L14-2 对烟草黑胫病的防治效果达到 96. 29%，K9-3 的防治效果为 77. 78%。同时，K9-3 和 L14-2 均具有良好的根际定殖能力，以双层滤纸法测定其在烟草根部的定殖密度分别为 1. 30 × 10 5 cfu·cm -1和 7. 00 × 104 cfu·cm-1，在盆栽试验中两菌株在烟草根际土壤和烟草根部保持一定的定殖密度，在烟草根际土壤中 的定殖密度随着时间经过有所下降，但在烟草根部定殖密度均稳定保持在 105 cfu·g －1 以上。另外，两菌株的鉴定结果，K9-3 鉴定 为普城沙雷菌，L14-2 鉴定为绿针假单胞菌。 关键词: 生防菌; 烟草黑胫病; 抑菌活性; 根际定殖; 鉴定 doi: 10. 3969 / j． issn． 1004-5708. 2011. 06. 018 中图分类号: S476 文献标识码: A 文章编号: 1004-5708( 2011) 06-0089-05 Antifungal activity of two biocontrol strains against tobacco black shank and their identification WANG Jing-jing，JIANG Shi-jun，CHANG Shu-xian，WANG Yong-jun，SHEN Shun-shan Henan Agricultural University，Zhengzhou 450002，China Abstract: Inhibitory ability of two biocontrol strains ( K9-3 and L14-2) against tobacco black shank was investigated with petri-dish，spore germination and pot experiments． The strains colonization capacities were determined with double layer filter paper method and pot experiment while their identification with morphological and physiological characteristics and 16S rDNA sequence analysis． In vitro experiments showed that the two strains can inhibit mycelial growth，germination of cystospores，and formation of zoospore and zoosporangia of Phytophthora nicotianae． Pot experiment showed that inhi- bition rate of K9-3 and L14-2 were 96． 29 % and 77． 78 %，respectively． The two strains showed good colonization ca- pacities，and their colonized concentration maintained at about 106 cfu·g －1 in root and over 5 × 104 cfu·g －1 in rhizo- sphere soil． Identification showed that K9-3 was Serratia plymuthica，L14-2 was Pseudomonas chlororaphis． Key words: biocontrol strain; tobacco black shank; antimicrobial activity; colonization; identification 作者简介: 王