【作者】 刘洁；

【导师】 张明方； 杨景华；

【作者基本信息】 浙江大学 ， 园艺（专业学位）， 2019， 硕士

【摘要】 西瓜(Citrulluslanatus)是葫芦科(Cucurbitaceae)西瓜属中的栽培种,重要经济作物之一,属于世界十大水果之列。随我国农业产业结构的调整和优化,西瓜的种植面积和产量已居世界首位。黄瓜绿斑驳花叶病毒(Cucumber green mottle mosaic virus,CGMMV)是侵染西瓜主要病毒病之一,是典型的种传病害,近几年田间发病较严重。西瓜植株受到CGMMV病毒侵染后会出现花叶、畸形叶、植物生长受阻、果实瓤色变紫等症状,导致产量降低和商品品质下降,严重时甚至绝产。本研究以抗CGMMV的野生西瓜种质’PI595203’和高感的栽培种’M1511-3’为亲本获得的F2遗传分离群体,分析了 CGMMV抗性遗传规律,利用基于全基因重测序的BSA方法初步定位了西瓜抗CGMMV的候选基因。主要结果如下:1)野生西瓜种质’PI595203’和栽培种’M1511-3’的抗性鉴定经机械摩擦接种CGMMV,通过调查’PI595203’和’M1511-3’病情指数、病毒基因的表达和ELISA检测分析,结果表明’P1595203’对CGMMV表现为抗性,’M1511-3’对CGMMV表现为高感。2)西瓜抗CGMMV基因的遗传分析以西瓜抗、感自交系’PI595203’和’M1511-3’为亲本,构建F2群体。对Fi(30株)、F2(320株)群体进行CGMMV机械摩擦接种鉴定抗性,Fi群体植株表现为感病,F2群体表型出现性状分离且呈正态连续分布,结果表明西瓜CGMMV抗性为数量性状,由多对隐性基因控制。3)西瓜抗CGMMV基因定位选取F2群体中感抗样品构建感病池和抗病池,并对其进行重测序。关联分析获得了 1个与抗病性状相关1.01Mb的候选区域,对该区域进行功能注释,共获得56个编码基因。更多还原

【Abstract】 Watermelon(Citrullus lanatus)belongs to Cucurbitaceae,as an important economic crop,is one of the top ten fruit crops.With the adjustment and improvement of agricultural structure,the planting area of watermelon in China has ranked the first in the world.Cucumber green mottle mosaic virus disease is a main disease affecting watermelon production,which is transmitted through seeds.Watermelon seedlings infected by CGMMV display some typical disease symptoms,such as mosaic patterns,abnormal leaves,stunting,abnormal fruit,necrosis,reduction in yield anddecline in quality.In this study,a wild type watermelon with resistance to CGMMV,’PI595203’,and a cultivar with high susceptibility to CGMMV,’M1511-3’,were used as parent lines to construct Fi and F2 population by hybridization and self-cross to analyse the inheritance of resistance to CGMMV.The resistant genes for CGMMV were preliminarily mapped by BSA method based on the whole genome sequencing.The main results were shown as follows:1)Resistance identification of ’PI595203’ and ’M1511-3’.’PI595203’and ’M1511-3’ were inoculated with CGMMV,and then symptoms investigation,CGMMV gene ex:pression analysis and ELISA test were performed.We found that ’PI595203’,was resistant.to CGMMV,while ’M1511-3’ was highly sensitive to CGMMV.2)Genetic analysis of CGMMV-resistance gene.The F2 population was deduced from the cross of the CGMMV resistance line’PI595203’and susceptible line’ M1511-3’.F1(30 individuals)and F2(30 individuals)were inoculated with CGMMV,respectively.We found that F1 progenies were susceptible.The traits were separated in hybrids F2 generation and showed Gaussian distribution,indicating that CGMMV-resistance phenotype is controlled by mulhi-recessive genes in watermelon.3)CGMMV-resistance gene mappingResistant individuals and susceptible individuals in the F2 population were selected for geneome-sequencing.One candidate region related to disease resistance traits was obtained,with the total interval of 1.01 Mb.Association analysis of genome sequences and resistance phenotype provide us 56 candidate genes.更多还原