内蒙古乌兰察布市马铃薯致病疫霉分离鉴定及特征分析

Isolation,Identification and Characteristic Analysis of Phytophthora Infestans on Potatoes in Ulanqab,Inner Mongolia

内蒙古乌兰察布市是我国重要的马铃薯产地,为研究该地区的晚疫病病原菌发生情况及特性,在该地田间采集患病马铃薯叶片并分离纯化致病疫霉菌株,进行分子鉴定、交配型鉴定、生长特性分析、耐药性检测和毒力测定。结果显示,从该地6个区分离到15株菌株,分离得率为41.7%,且分离到的菌株以菌丝生长速率一般型为主,占比73.00%。多数菌株生长耐受温度范围在10℃~24℃、26℃之间。该地以弱致病型性菌株占比最高,其次是一般型菌株。该地鉴定到13株A1交配型菌株,2株A2交配型菌株。针对精甲霜锰锌和银法利的耐药性,对精甲霜锰锌的高抗型菌株占比86.67%,对银法利的高抗型菌株占比60.00%,以高抗型菌株占比最高。分离到的菌株弱致病性菌株比例最高,占比达46.67%,强致病性菌株比例最少,占比20.00%。研究揭示了乌兰察布市致病疫霉的特征特性,为马铃薯晚疫病的防治提供了思路。

Ulanqab is an important potato producing place in China.To study the occurrence and characteristics of late blight patho-gens in this area,diseased potato leaves were collected in the fields,and Phytophthora infestans strains were isolated and purified.The molecular and mating type identification,growth characteristics analysis,drug resistance detection,and pathogenicity test were conducted.The results showed that,15 strains were obtained from six regions,the isolating frequency were 41.7%.The strains iso-lated were mainly medium growth type of mycelial,accounting for 73.00%.The growth temperature range of most strains was be-tween 10℃ and 24℃ or 26℃.In this area,the weak pathogenic strains made up the highest proportion,followed by the general pathogenic strains.A total of 13 strains of Al mating type,and 2 strains of A2 mating type,were identified.For the drug resistance to Metalaxyl mancozeb and Infinito,highly resistant strains were the majority.The highly resistant strains to Metalaxyl mancozeb ac-counted for 86.67%,and the highly resistant strains to Infinito accounted for 60.00%.Whereas,for the pathogenicity,the propor-tion of weak pathogenic strains was the highest,accounting for 46.67%,and that of strong pathogenic strains was the lowest,ac-counting for 20.00%.The research revealed the properties of Phytophthora infestans strains in Ulanqab,and provided ideas for the prevention and treatment of late blight on potato.