甘肅省定西市馬鈴薯瘡痂病新病原Streptomyces galilaeus的分離、鑒定及生物學特性研究

崔凌霄 楊成德 魏立娟 薛莉 張俊蓮

摘要

對甘肅省定西市安定區的馬鈴薯瘡痂病病原進行了分離、鑒定和生物學特性研究。結果表明，菌株5T-1具有較強致病性，菌落表面呈灰色，有金屬光澤，平均直徑為4.68 mm，可產生黃褐色素，孢子圓形或圓柱形，孢子絲松散，革蘭氏染色呈陽性。5T-1的16S rDNA序列與加利利鏈霉菌Streptomyces galilaeus菌株的相似度為99%，結合形態特征將菌株5T-1鑒定為Streptomyces galilaeus，為甘肅省新報道病原菌。菌株5T-1生長最適溫度為30℃，最適光照條件為全黑暗，最適pH為8.5，最佳碳源和氮源分別為肌醇和天冬氨酸。該研究結果為甘肅省馬鈴薯瘡痂病診斷和綜合防治提供了依據。

關鍵詞

馬鈴薯瘡痂病; 病原; 16S rDNA序列分析; 鑒定; 生物學特性

中圖分類號：

S 435.32

文獻標識碼： A

DOI： 10.16688/j.zwbh.2018109

Isolation， identification and biological characterization of Streptomyces galilaeus，

a new pathogen of potato scab in Dingxi City， Gansu Province

CUI Lingxiao YANG Chengde WEI Lijuan XUE Li ZHANG Junlian2

（1. Laboratory of Biocontrol Engineering of Crop Pests and Diseases in Gansu Province， College of

Plant Protection， Gansu Agricultural University， Lanzhou 730070， China; 2. Gansu Key Lab of

Crop Improvement & Germplasm Enhancement， Lanzhou 730070， China）

Abstract

The pathogen of potato scab from Anding District of Dingxi City in Gansu Province was isolated and identified， and its biological characteristics were also determined. The results showed that the strain 5T-1 was highly pathogenic. The colony was gray with a metallic luster and the average diameter of 4.68 mm， which could produce yellow brown pigment. The spores were round or cylindrical and spores silk was loose. Gram staining is positive. The similarity of 16S rDNA sequence of 5T-1 to that of Streptomyces galilaeus was 99%. Combining with the morphological characteristics， the strain 5T-1 was identified as S.galilaeus. It is a newly reported pathogen in Gansu Province. The optimal temperature for strain growth was 30℃. The optimal illumination conditions were darkness and the optimal pH value was 8.5. The best carbon source and nitrogen source were inositol and aspartic acid， respectively. The results provide a basis for the diagnosis and integrated control of potato scab in Gansu Province.

Key words

potato scab; pathogen; 16S rDNA sequence analysis; identification; biological characteristics

馬鈴薯為繼玉米、小麥和水稻之后的世界第四大糧食作物[1]，分布廣，種植便捷，產量高，是備受人們喜愛的經濟作物之一。甘肅省是國內馬鈴薯種植大省，尤其定西馬鈴薯更是世界聞名。但是，隨著種植面積擴大，重茬嚴重，致土傳病害嚴重發生，特別是馬鈴薯瘡痂病近年來成為甘肅省定西市薯塊主要病害之一。馬鈴薯瘡痂病在世界各地馬鈴薯種植區普遍發生[2]，其在薯塊上形成褐色木栓化病斑，發病嚴重時，病斑成片，嚴重影響薯塊品質和商品性。據報道，引起馬鈴薯瘡痂病的病原為鏈霉菌，國內外報道的種主要有Streptomyces scabies、S.acidiscabies、S.turgidiscabies、S.europaeiscabiei、S.bobili、S.reticuliscabiei和S.griseus等[2-6]，其中S.scabies發現最早，分布最廣。我國不同省份報道的瘡痂鏈霉菌存在差異，內蒙古自治區有S.scabies、S.galilaeus和S.bobili[7]，甘肅省有S.scabies和S.griseus[8]，黑龍江省有S.scabies、S.turgidiscabies和S.acidiscabies[9]。……