【作者】 芦燕；

【导师】 张鲁刚；

【作者基本信息】 西北农林科技大学 ， 园艺植物种质资源学， 2008， 硕士

【摘要】 大白菜黑腐病是我国大白菜日益严重的主要病害之一。为加快大白菜抗黑腐病的新品种选育和种质创新步伐,方便、快速、准确的鉴定种质资源的抗病性就成为迫切需要解决的问题。本研究在对陕西省大白菜主产区黑腐病菌采集分离鉴定的基础上,进行了菌致病型的分化,研究进一步以致病力强的黑腐病病菌株做菌源,进行了幼苗期抗病性鉴定方法,室内快速鉴定方法等研究,同时还对不同大白菜品种和种质进行了抗病性鉴定研究,主要研究结果如下:1、从陕西省大白菜主产区采集分离35个大白菜黑腐病菌株,根据抗、感反应一致性将35个大白菜黑腐病菌株划分为I、II、III、IV、V、VI 6个致病型,其中III型致病力最强;II型为典型的致病型;I、IV、V型的致病专化性强,品种间抗感差异最大;I、V型的致病力相当;VI型的致病力与其他菌株差异最大。2、大白菜黑腐病6个致病型在陕西省大白菜主产区发病程度有明显差异,其中I、V致病型在陕西省4个大白菜主产区均有发生,研究确定I致病型是陕西省大白菜黑腐病的主要菌原。同时发现黑腐病病菌致病力与其淀粉水解能力和明胶液化程度呈正相关。3、建立了优化的大白菜黑腐病苗期人工接种鉴定方法,即接种方法采用喷雾法,接种菌量为1.0×108 cfu/mL,接种时期为4~5叶期,发病温度控制26℃,病程过程为12d。4、建立了活体子叶、离体子叶和离体叶片人工接种鉴定方法,活体子叶接种鉴定中以22℃,1.0×1010 cfu /mL浓度下喷雾法接种最好;离体子叶接种鉴定以22℃,1.0×1010 cfu/mL浓度下滴接法接种最好;离体叶片接种鉴定中,以26℃,1.0×108 cfu /mL浓度下滴接法接种最好;三种简易接种方法比较得出以离体叶片法最能真实反映抗病性。5、对344份大白菜材料进行了抗病性鉴定结果表明,没有免疫品种;有12份高抗材料,分别是:秦白2号♂、秦白3号♂、金冠1号、06S317、06S1692、07S11、07S12、07S140、07S544、07S544、06S40、99S26-M;52份抗病材料;156份耐病材料;121份材感病料;4份高感材料,分别为:07S158、06S658、06J30、06S49。更多还原

【Abstract】 Chinese cabbage black rot disease is growing increasingly as one of the main diseases in China, Therefore, an urgent problem is to setup a convenient, rapid and exact method for identify the resistance of germplasm resources Chinese cabbage (Brassica campestris L. ssp penkinsis) to black rot, which will promote the step of germplasm and new varity breeding. In this research, the pathogenic bacteria was isolated from the disease samples of shaanxi Chinese cabbage field and its pathotype differentiation has been done with various resistance Chinese cabbage varities. then the methods of identification of black rot disease resistance were optimized at seedling stage, cytoledon stage,in vitro cytoledon or seedling leaf respectively. Lastly, the resistance of germplasm resources and hybrids of Chinese cabbage were tested in seedling stag. the major results were as follows:1. First, The 35 Chinese cabbage black rot strains were isolated from the disease samples collected from the major Chinese cabbage production area of Shaanxi Province. The 6 black rot strains with different pathogenicity on Chinese cabbage had been distinguished by the resistance or susceptibility in host-pathogen interaction, which is coded as I, II, III, IV, V and VI, thereinto, type III had the strongest infection capacity, type II was the typical pathogenic strain, type I, IV and V had high host specificity, type I and V had the similar infection capacity and type VI was obviously different with others bacteria strains in infection capacity.2. It was obvious differences that the 6 kinds of pathogenicity occur at Chinese cabbage production area of Shaanxi Province, such as type I and V occurred at four Chinese cabbage production areas, and type I was the major pathogenic bacteria in all areas. In addition, it was found that there was a positive correlation between the pathogenicity and ability of hydrolyzing starch and extent of gelatin liquefaction in bacteria.3. The optimal artificial inoculation and identification method for black rot of Chinese cabbage at seedling stage was established. The key procedures is that inoculating by spray method with 1.0×108 cfu/mL bacteria quantity on the seedling of 4~5 true leaves stage, then kept at 26℃for 12 days.4. The inoculation and identification method at cotyledon stage , in vitro cotyledon or seedling leaf also established. Spray method with 1.0×1010cfu/mL bacterium liquor at 22℃was suitable for cotyledon stage identification, dirpping method with 1.0×1010cfu/mL of bacterium liquor at 22℃was suitable for in vitro cotyledon identification, dirpping method with 1.0×108cfu/mL of bacterium liquor at 26℃aslo was suitable for in vitro seedling leaf identification. It was noted that the method of in vitro seedling leaf identification was best to reflect the truth of resistance to black rot.5. The resistance of 344 germplasms of chinses cabbage were identified at seedling stage, its result showed that there was no immune accession, there was 12 accessions with high resistance, 52 with resistance, 156 with tolerance, 121 with susceptivity and 4 with high susceptivity. The high resistance accessions were Qinbai No2♂, Qinbai No3♂, Jinguan No1, 06S317, 06S1692, 07S11, 07S12, 07S140, 07S544, 07S544, 06S40 and 99S26-M. The high susceptivity accession were 07S158, 06S658, 06J30 and 06S49.更多还原