本文選題：致病疫霉 + 群體遺傳��； 參考：《內(nèi)蒙古大學(xué)》2017年碩士論文

【摘要】：馬鈴薯晚疫病是由致病疫霉[Phytophthora infestans(Mont.)de Bary]引起的馬鈴薯上最嚴(yán)重的病害之一。了解馬鈴薯晚疫病菌群體遺傳結(jié)構(gòu)的組成情況,對(duì)明確病害發(fā)生及流行規(guī)律具有重要意義,為馬鈴薯晚疫病的有效防控提供重要理論依據(jù)。本研究對(duì)中國(guó)馬鈴薯主產(chǎn)區(qū)采集的晚疫病病原菌致病疫霉菌樣品分離純化,從交配型、甲霜靈抗性和SSR分子標(biāo)記三個(gè)方面,描述群體結(jié)構(gòu)特征,分析群體多樣性。對(duì)2015年采自云南、四川、貴州、湖北、內(nèi)蒙古、黑龍江共六個(gè)主產(chǎn)區(qū)的樣本進(jìn)行分離純化,分離到213株P(guān).infestans菌株。同時(shí),利用FTA采樣卡采集91株樣品。利用皿內(nèi)對(duì)峙法對(duì)213株菌株的交配型進(jìn)行檢測(cè),結(jié)果表明內(nèi)蒙古地區(qū)菌株均是A1交配型,其他地區(qū)菌株以A2交配型為主,其中貴州、黑龍江、四川的晚疫病菌中A1、A2兩種交配型同時(shí)存在。在甲霜靈抗性檢測(cè)中,甲霜靈高抗菌株占25.82%、中抗菌株占72.77%、敏感菌株占1.41%。中度抗性和高度抗性菌株在所有地區(qū)所占比例都超過(guò)80.00%,其中內(nèi)蒙古地區(qū)無(wú)敏感性菌株,高度抗性菌株超過(guò)80.00%。選用4種熒光標(biāo)記的12對(duì)SSR引物對(duì)213株樣品基因型進(jìn)行鑒定,共鑒定出73個(gè)不同的基因型,北方地區(qū)以MLG 50、MLG 71基因型為主;南方地區(qū)無(wú)明顯優(yōu)勢(shì)型。僅有少量基因型同時(shí)出現(xiàn)在南北方,如MLG 20基因型出現(xiàn)在黑龍江和湖北,MLG 50出現(xiàn)在云南和黑龍江,MLG 61出現(xiàn)在云南、四川和黑龍江�；赟SR多態(tài)性的聚類分析結(jié)果顯示,南方和北方晚疫病群體菌株間的親緣關(guān)系較遠(yuǎn),遺傳背景存在顯著差異�；赟SR測(cè)序數(shù)據(jù),進(jìn)行主成分分析(PCA)和分子方差分析(AMOVA)。分子方差分析結(jié)果表明不同省份間晚疫病菌基因型差異顯著,變異主要來(lái)源于省份間而非省份內(nèi)部。主成分分析結(jié)果顯示所有菌種樣本分為三個(gè)類群(Group)。Group Ⅰ主要包含湖北地區(qū)樣品,GroupⅡ主要包含內(nèi)蒙古地區(qū)樣品,GroupⅢ主要包括云南、四川、貴州地區(qū)樣品。以上結(jié)果表明菌種類群與地域來(lái)源相關(guān)。
[Abstract]:Potato late blight is one of the most serious potato diseases caused by Phytophthora infestans [Phytophthora infestans(Mont.)de Bary]. Understanding the composition of population genetic structure of potato late blight fungus is of great significance to clarify the occurrence and epidemic law of potato late blight and provide important theoretical basis for the effective prevention and control of potato late blight. In this study, samples of Phytophthora infestans collected from the main potato producing areas in China were isolated and purified. The population structure and diversity were described and analyzed from three aspects: mating type, metalaxyl resistance and SSR molecular markers. Two hundred and thirteen strains of P.infestans were isolated from six main producing regions of Yunnan, Sichuan, Guizhou, Hubei, Inner Mongolia and Heilongjiang in 2015. At the same time, 91 samples were collected by FTA sampling card. The mating type of 213 strains was detected by in-dish confrontation method. The results showed that all the strains in Inner Mongolia were A1 mating type, while the other strains were A2 mating type, including Guizhou, Heilongjiang, Heilongjiang. There are two mating types of A _ 1 A _ 2 in late blight bacteria in Sichuan. In the detection of metalaxyl resistance, the percentage of high resistant strains was 25.82, the antibacterial strain was 72.77 and the sensitive strain was 1.41%. The proportion of moderately resistant and highly resistant strains in all regions was more than 80.00.Among them, there were no sensitive strains in Inner Mongolia region, and more than 80.00g strains with high resistance strains in Inner Mongolia. A total of 73 different genotypes were identified by using 12 pairs of SSR primers with four fluorescent markers. The dominant genotype of MLG 50 MLG71 was found in the northern region, but there was no obvious dominant genotype in the southern region. Only a few genotypes appeared in the south and north, such as the MLG 20 genotype appeared in Heilongjiang and Hubei Province, the MLG50 appeared in Yunnan and Heilongjiang, Sichuan and Heilongjiang appeared in Yunnan, Sichuan and Heilongjiang. The results of cluster analysis based on SSR polymorphism showed that the relationship between the strains of late blight in the south and the north was far away, and the genetic background was significantly different. Based on SSR sequencing data, principal component analysis (PCA) and molecular variance analysis (AMOV A) were performed. The results of molecular variance analysis showed that the genotypes of late blight bacteria were significantly different among different provinces, and the variation was mainly from different provinces rather than from within provinces. The results of principal component analysis showed that all the samples were divided into three groups, Group.Group 鈪，

本文編號(hào)：1939553