西葫芦抗白粉病遗传分析及基因定位初步分析

发布时间：2018-03-05 18:32

本文选题：西葫芦　切入点：白粉病　出处：《河北工程大学》2017年硕士论文　论文类型：学位论文

【摘要】：白粉病是瓜类作物普遍发生的世界性真菌病害,流行性强,而且频繁侵染植物,其潜育周期较短。在西葫芦的生产上,因感染白粉病常常造成极大的经济损失。学者专家们也多次研究防治白粉病的方法,传统上多采用化学药剂防治白粉病,但化学药剂对环境造成极大的污染,并且成本也高,尤其是还会影响西葫芦的品质,食用安全性降低。因此,选育具有白粉病抗性的西葫芦品种是至关重要的。本研究以具有抗性的西葫芦自交系BS6(P1)和感病自交系BS11(P2)为亲本构建六世代遗传分离群体(F_1、F_2、BC1P1、BC1P2),通过对各群体单株进行白粉病抗性分析,明确西葫芦白粉病抗性遗传规律,并对抗病基因进行了遗传定位。研究结果如下:(1)根据鉴定结果对西葫芦抗白粉病基因进行遗传分析,结果显示BS6×BS11的F_1均表现为抗病,在F_2群体中,抗病与感病植株的分离比例符合3:1;BC1P1群体60株,均表现为抗病性,在BC1P2群体中,抗病与感病植株的分离比例符合1:1。表明,西葫芦白粉病抗性由一对显性抗病基因控制,命名为Pm-1。(2)利用743对SSR标记筛查亲本间多态性分子标记,其中有68对在双亲间表现出多态性,结合BSA方法,在抗、感病基因池间有5对标记表现为多态性。(3)进一步利用F_2群体的抗性鉴定结果,对获得的5对分子标记进行分析,其中分子标记SSR14和SSR237与抗病基因连锁最为紧密,抗病基因Pm-1被定位在标记SSR14和SSR237之间,距离两侧翼标记的遗传距离分别是8.7和5.2cM。(4)为进一步验证遗传定位结果,以F_1与抗病亲本回交获得BC1P2群体为试验材料,应用分子标记SSR237进行基因分析,分子标记的基因型结果与单株的抗性表型结果非常符合,表明SSR237与抗病基因紧密连锁,可以用于分子标记辅助选择育种。
[Abstract]:Powdery mildew is a worldwide fungal disease commonly occurring in melon crops. It is highly epidemic and infects plants frequently, and its latent breeding period is relatively short. In the production of zucchini, Since powdery mildew infection often causes great economic losses, scholars and experts have also studied the methods of preventing powdery mildew many times. Traditionally, chemical agents have been used to control powdery mildew, but chemical agents have caused great pollution to the environment, and the cost is also high. In particular, it will affect the quality of zucchini and reduce the food safety. The breeding of squash varieties with powdery mildew resistance is very important. In this study, we constructed a six-generation genetic segregated population of Cucurbita squash (BS6P1) and susceptible inbred line BS11P _ 2 (BS11P _ (2)) to construct a six-generation genetic segregated population, which was constructed by means of single plant of each population. Analysis of powdery mildew resistance, The genetic rules of resistance to powdery mildew of squash were clarified and genetic mapping of resistance genes was carried out. The results were as follows: 1) genetic analysis of powdery mildew resistance genes of squash was carried out according to the identification results. The results showed that F1 of BS6 脳 BS11 showed resistance to powdery mildew. In FStu2 population, the segregation ratio of resistant and susceptible plants was consistent with that of 3: 1 BC1P1 population (60 plants). In BC1P2 population, the segregation ratio of disease-resistant and susceptible plants was 1: 1.The results showed that the segregation ratio of disease-resistant and susceptible plantlets was 1: 1.The results showed that the segregation ratio of disease-resistant and susceptible plants was 1: 1. The resistance of squash powdery mildew was controlled by a pair of dominant resistance genes, named Pm-1.2.) 743 pairs of SSR markers were used to screen polymorphic molecular markers among parents, 68 of which showed polymorphism between parents. Five pairs of markers among susceptible gene pools were polymorphic. (3) five pairs of molecular markers were analyzed by using the results of F-2 population resistance identification. The molecular markers SSR14 and SSR237 were most closely linked to disease resistance genes. The resistance gene Pm-1 was located between the marker SSR14 and SSR237, and the genetic distance between the two flanking markers was 8.7 and 5.2 cm. 4) in order to further verify the genetic location results, the BC1P2 population was obtained by backcrossing FAP1 with disease-resistant parents. The results of genetic analysis with molecular marker SSR237 showed that the genotypes of molecular markers were in good agreement with the results of resistance phenotypes of individual plants, indicating that SSR237 was closely linked to resistant genes and could be used in molecular marker-assisted selection breeding.
【学位授予单位】：河北工程大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S436.429

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