【作者】 林琳；

【导师】 杨景华； 张明方；

【作者基本信息】 浙江大学 ， 园艺（专业学位）， 2015， 硕士

【摘要】 甜瓜是世界十大水果之一,广泛种植于温带和热带地区,已作为一种重要的经济作物在世界各地普遍栽培。枯萎病、白粉病和蔓枯病是影响甜瓜产量和质量的三大主要病害,多年来一直成为限制甜瓜产业发展的障碍,造成甜瓜不同程度的减产和低质。物理防治、化学防治和生物防治是农业防治病害的三大举措,但都无法有效预防这三种病害的发生,而抗病种质鉴定与抗病品种选育可以从根本上为甜瓜抗枯萎病、白粉病和蔓枯病提供有效途径,从而有效防治这三大病害的发生。本论文基于实验室自主开发的甜瓜枯萎病分子标记和查找到的白粉病、蔓枯病分子标记,筛选鉴定了甜瓜抗枯萎病、白粉病和蔓枯病种质资源,在厚皮甜瓜与薄皮甜瓜亚种间远缘杂交及回交过程中,通过分子标记辅助选择,快速筛选抗病种质,加速育种进程,主要研究结果如下：1.抗病种质筛选基于甜瓜抗枯萎病生理小种0,1功能性分子标记、抗枯萎病生理小种0,2的SCAR标记SVO1s74、抗白粉病SCAR标记及抗蔓枯病基因分子标记,鉴定了17种甜瓜种质资源对三种病害的抗性。发现了对枯萎病生理小种0,2有抗性的种质14个,对枯萎病生理小种0,1有抗性的种质16个,对白粉病有抗性的种质13个,对蔓枯病有抗性的种质14个。2.甜瓜亚种间远缘杂交与回交以对三种病害具有不同抗性的厚皮甜瓜(哈密瓜类型)与薄皮甜瓜进行亚种间远缘杂交及回交,在F1、BC1、BC2回交世代中,采用抗枯萎病、白粉病和蔓枯病三种分子标记进行筛选,鉴定到了F1代17株单株含有对枯萎病生理小种0,1,2的抗性基因,其中1株单株兼具对白粉病的抗性基因；BC1代37株单株含有对枯萎病生理小种0,1,2的抗性基因；BC2代13株单株含有对枯萎病生理小种0,1,2的抗性基因兼具蔓枯病抗性基因。3.回交后代的田间表现和果实的考种对BC2代株系的田间生长发育进行了观察,发现筛选出的株系在田间的抗病性有了大大的提高,抗病性远远高于厚皮甜瓜亲本。并对其果实进行了考种,得知回交后代果实质量较受体亲本并没有降低,说明用分子标记辅助选择育种技术与传统育种技术相结合,能够有效地筛选出兼具抗病性和优良品质的新种质。更多还原

【Abstract】 Melon (Cocumis melo. L) is one of the most important horticultural crops which is widely cultivated in the temperate and tropical regions. Fusarium wilt, powdery mildew and gummy stem blight are three major diseases world-wide in melon, which have a huge impact on melon’s yield and quality. Physical, chemical and biological control of these diseases is ineffective. Therefore, identification of disease-resistant germplasms and breeding new varieties is the most effective and fundamental way to eliminate these diseases.This research was based on utilizing the molecular markers to identify fusarium wilt, powdery mildew and gummy stem blight disease resistant melon germplasms. During distant hybridization and backcross between thick-skin muskmelon and thin-skin muskmelon, disease-resistant melon germplasms were identified by marker-assisted selection(MAS). The main research results are as follows:1Identification of disease-resistant germplasms17varieties of melon germplasms have been identified based on a FMs which is resistant to race0,1of Fusarium oxysporum f.sp.melonis, an SCAR marker-SV04574which is resistant to race0,1of Fusarium oxysporum f.sp.melonis, a powdery mildew-resistant SCAR marker and a gummy stem blight-resistant ISSR marker. We got14materials resistant to race0,1of Fusarium oxysporum f.sp.melonis and16materials resistant to race0,2of Fusarium oxysporum f.sp.melonis,13materials resistant to powdery mildew,14materials resistant to gummy stem blight.2Distant hybridization and backcross of melonTwo thick-skin muskmelon species and a thin-skin muskmelon species were used to proceed distant hybridization and backcross. The four kinds of molecular markers have been used in screening resistant plants in F1， BC1,BC2groups. Through which,17Fi plants with fusarium wilt-resistant gene, include one plant resistant to powdery mildew,37BCi plants with fusarium wilt-resistant gene,13BC2plants with fusarium wilt and gummy stem blight-resistant gene have been identified. 3Observation of phenotype of backcross descendants and fruit testingVia observation of phenotype of backcross descendants in the field, we found the resistance has been greatly improved without any weakening in flavor compared to thick-skin muskmelon parents. The result illustrated that the MAS is an efficient way to select new cultivars possessing disease resistance and high quality.更多还原