【作者】 邹燕；

【导师】 程智慧；

【作者基本信息】 西北农林科技大学 ， 园艺植物种质资源学， 2009， 硕士

【摘要】 大蒜紫斑病是大蒜的主要真菌性病害之一,药物防治存在农药残留问题,选育抗紫斑病且高产的优良大蒜品种具有重要意义。本研究首次对大蒜紫斑病[Alternaria porri (ELL.) Cif.]的抗病性鉴定方法及大蒜种质资源的抗病性进行了研究,并运用灰色关联理论分析了蒜头产量与其构成性状的关系,为大蒜品种资源评价及育种和大蒜栽培中的品种选择提供参考。以G087(抗病)、G064(中抗)、G073(感病)为鉴别品种,对大蒜紫斑病的侵染途径,抗性鉴定的接种叶龄、接种浓度、接种部位,接种后培养温度及调查时期等进行了研究。结果表明,苗期紫斑病菌通过伤口和自然孔口均可浸染大蒜植株,而花芽鳞芽分化期只可通过伤口侵入。抗病性鉴定最适接种叶龄为5叶期;最适接种浓度为106孢子·ml-1;离体接种法较活体接种法更简便快捷。离体接种鉴定时,叶面接种和叶背接种鉴定结果无显著性差异;接种后最适培养温度为21℃;最适调查时期为接种后第6 d。以G057(抗病)、G103(中抗)、G083(感病)为大蒜验证品种,离体接种鉴定结果显示,建立的大蒜紫斑病抗病性鉴定方法可行,能如实反映品种的真实抗性。用所建立的鉴定方法对45个大蒜品种进行了鉴定和评价。供试品种中没有发现对大蒜紫斑病免疫的品种;G104、南欧蒜(G093)、G097等3个为高抗品种;G095、G057、G087、G102、G039、G015、G075、G100、G007、G026等10个为抗病品种;G059、G004、G098、G064、G094、G101、G087抽薹、G005、G103、G020、G084等11个为中抗品种;G029、G096、G099、G008、G018、G088、G091、G074、G090、G073、G022、G083、G089、G024-x、G085等15个为感病品种;高感品种有6个,为G074-x、G023、G086、G009、G025、G092。运用灰色关联分析理论对与蒜头产量相关的11个大蒜主要产量性状进行关联度评价。认为与蒜头亩产量关系最密切的是1层蒜瓣重,关联度为0.851;其次是单头重,再次依次为2层瓣重、假茎粗、蒜头周长、蒜头直径、2层瓣数、蒜头高、1层瓣数、株高、叶数;关系最远的是叶数,关联度是0.755。因此,要培育高产品种,应从提高1层瓣重、单头重、2层瓣重等性状入手进行选择,并注意选择生殖生长初期假茎粗的材料。更多还原

【Abstract】 The garlic violet leaf spot [Alternaria porri (ELL.) Cif.] is one of the main fungal diseases of the garlic, medicine prevention has disadvantages due to existing drug residual, therefore, it is important significance to select and breed fine garlic cultivars which are resistant to garlic violet leaf spot and also have high yield. The research focuses on the resistance identification method, the germplasm resources resistance to garlic violet leaf spot, the relationship between bulb yield and its component traits by grey correlation thoery for the first time, which provides reference for the garlic germplasm evaluation, breeding and the varietal selection in the cultivation.The infection path of garlic violet leaf spot and resistance identification of inoculation leaf stages, inoculation spore concentration, inoculation position, culture temperature after inoculation and time to survey etc were studied by using the identification cultivars G087 (R), G064 (MR), and G073 (S). The results revealed that, the pathogen of violet leaf spot infects garlic plants through both the wound and the natural orifices at seedling stage however, at flower bud differentiation stage it only invades through the wound. For disease resistance identification, the optimal leaf stage is 5-leaf stage.the optimal spore concentration is 106 spore ? ml-1. Inoculation in vitro is more simple and rapid as compared to inoculation in vivo. For in vitro inoculation, there is no significant difference between leaf face surface inoculation and leaf back surface inoculation. the optimal culture temperature after inoculation is 21℃and the optimal time to survey disease index is the 6th day after inoculation. Using G057 (R), G103 (MR), and G083 (S) as the verification cultivars, the results showed that the established method is practicable to reflect the true resistance of garlic cultivars to violet leaf spot.45 garlic cultivars were identified and evaluated by the method which had been established. There is no one which is immune to the garlic violet leaf spot amongst the tested cultivars. G104, Southern Europe Garlic (G093), G097 etc, 3 cultivars are high-resistant; G095, G057, G087, G102, G039, G015, G075, G100, G007, G026 etc, 10 cultivars are resistant; G059, G004, G098, G064, G094, G101, G087 bolting, G005, G103, G020, G084 etc, 11 cultivars are mid-resistant and G029, G096, G099, G008, G018, G088, G091, G074, G090, G073, G022, G083, G089, G024-x, G085 etc, 15 cultivars are sensitive. The 6 high-sensitive cultivars are G074-x, G023, G086, G009, G025, G092.Gray relational analysis theory was applied to evaluate the 11 garlic main yield characters which related to bulb yield by relational degree. It is considered that the 1st layer clove weight showed the closer relationship with bulb yield per 667㎡, the relational degree is 0.851 fallowed by the bulb weight, however the remaining next the order of the relational degree is the 2nd layer clover weight, stem diameter, bulb girth, bulb diameter, 2nd layer clove number, bulb height, 1st layer clove number, plant height, leaf number and the leaf number has the farthest correlation to it having the relational degree is merely 0.755. Therefore, it is concluded that if high bulb yield is demanded for cultivation, we should start with the characters of the 1st layer clove weight followed by the bulb weight, the 2nd layer clover weight etc and pay more attention to the materials that have thicker pesudostem in the process of the cultivar selection.更多还原