甘蓝种质资源根肿病抗性鉴定及CRa、Crr1a同源基因分析

利用来源于湖北长阳、陕西太白、河南新野3个地方的根肿病菌对22份不同甘蓝材料进行抗病性鉴定。采用同源比对的方法,对甘蓝基因组中的大白菜抗根肿病同源基因CRa和Crr1a进行分析;同时对不同抗、感根肿病甘蓝材料中的CRa和Crr1a同源基因序列进行了扩增、测序和比对分析。结果表明:供试22份甘蓝材料对3份根肿病菌存在较大的抗感差异,推测来源于3个地区的菌种可能不是同一个生理小种;筛选出的抗性品种BDH3、Chou hybride Tekila、SW-110、CGL-8、先正达品种、SW-109将来可用作根肿病抗源和抗性基因挖掘;在甘蓝7号染色体上存在3个预测基因为CRa的同源基因,分别是Bo7g107710、Bo7g107730和Bo7g107740,其中,Bo7g107730基因在抗病材料SW-110存在较大的序列变异,推测可能与根肿病抗性相关;在甘蓝3号染色体上存在1个预测基因Bo3g164040为Crr1a的同源基因,所分析的抗、感病材料中Bo3g164040基因序列一致性极高,没有发现与抗根肿病有关的位点,说明甘蓝中Bo3g164040基因可能没有根肿病抗性功能。

Identification of Cabbage Germplasms Resources with Resistance to Clubroot and Sequence Analysis of CRa and Crr1a Homologous Genes from Cabbage

Three pathogenic samples of Plasmodiophora brassicae from Changyang in Hubei Province, Taibai in Shanxi Province, and Xinye in Henan Province were used for inoculation to evaluate the clubroot disease resistance of 22 cabbage materials, respectively. The homologous genes of CRa and Crr1a in Brassica oleracea genome were analyzed by sequence homology analysis and then were amplified, sequenced and alignment for analysis. The results showed that 22 cabbage materials showed different resistance spectrum to three P. brassicae samples, indicating that three pathogenic samples were different physiological races. Screened resistant materials BDH3, Chou hybride Tekila, SW-110, CGL-8, Syngenta varieties, SW-109 could be used as clubroot-resistant breeding materials and mining new resistance gene in the future. Three genes (Bo7g107710, Bo7g107730 and Bo7g107740) on chromosome 7 of B. oleracea genome were identified as homologues of CRa, and the DNA sequence of Bo7g107730 gene showed relatively high variation in resistant material SW-110, which may be related to clubroot resistant. In addition, only one gene Bo3g164040 homologue to Crr1a were identified on chromosome 3 of B. oleracea genome, and we speculated that this gene was not resistant to clubroot disease because of this gene showed high sequence identity between resistant and susceptible material.