马铃薯疮痂病拮抗菌JYC1217的鉴定及其生防促生特性

为获得防治马铃薯疮痂病的优良微生物资源，从健康马铃薯根际土壤中分离获得菌株JYC1217，采用平板对峙培养法和抑菌圈法测定其抑菌活性，结合形态学特征、生理生化特性和分子生物学方法对该菌株进行鉴定，并测定该菌株的生防能力、促生能力及对马铃薯疮痂病的防效。结果显示，菌株JYC1217及其培养液均能显著抑制酸性疮痂链霉菌Streptomyces acidiscabies和肿痂链霉菌S. turgidiscabies的生长；经鉴定菌株JYC1217为多黏类芽胞杆菌Paenibacillus polymyxa；该菌株对马铃薯疮痂病的相对防效为35.12%，对晚疫病菌Phytophthora infestans和早疫病菌Alternaria alternata有抑制作用，抑制率分别为62.96%和64.24%；该菌株能产生β-1，3葡聚糖酶、纤维素酶、蛋白酶和嗜铁素，还可形成复杂生物膜结构，具有固氮、产1-氨基环丙烷-1-羧酸脱氨酶特性，能显著提高马铃薯叶片内苯丙氨酸解氨酶、多酚氧化酶和过氧化物酶活性；该菌株能溶解磷酸钙、大豆卵磷脂和碳酸镁，可显著增加马铃薯株高、叶绿素相对含量、茎粗和单株产量，表明菌株JYC1217是一株生防促生性状优良的生防菌，具有良好的开发应用潜力。

Identification of the antagonistic strain JYC1217 against potato common scab and its biocontrol and growth-promoting properties

To provide excellent microbial resources for the prevention and control of potato common scab disease, strain JYC1217 was isolated from the healthy rhizosphere, and its antimicrobial activity was screened and verified with plate culture and inhibition zone method. Its taxonomic status was determined by combining morphological, physiological and biochemical characteristics, and polygene sequence analysis. Its biocontrol ability, growth promoting ability, and control efficacy against potato common scab were measured. The results showed that the strain JYC1217 and its culture medium could significantly inhibit the growth of Streptomyces acidiscabies and S. turgidiscabies. The strain JYC1217 belongs to the bacterium Paenibacillus polymyxa, the prevention and treatment efficacy of this strain on potato common scab disease was 35.12%; it had inhibitory activity against Phytophthora infestans and Alternaria alternata, with inhibition rates of 62.96% and 64.24%, respectively. This strain could produce β-1,3-glucanase, cellulase, protease, and ferritin, and form complex biofilm structures; it showed the characteristics of nitrogen fixation and 1-aminocyclopropane-1-carboxylic acid deaminase production, and significantly enhanced the activities of phenylalanine ammonia-lyase, polyphenol oxidase, and peroxidase in potato leaves. This strain could dissolve calcium phosphate, soybean lecithin, and magnesium carbonate, and significantly increased potato plant height, relative chlorophyll content, stem diameter, and single plant yield. Thus, the strain JYC1217 should be a biocontrol bacterium with excellent growth promoting properties and has promising potential for development and application.