甜菜新型雄性不育细胞质（K-5）线粒体基因结构及不育机制研究

Sugar beet(beta vulgaris) belongs to one of typical hybrid crops.Owen cytoplasm is sole cytoplasm for sugar beet hybrid seeds production at present. Germplasm is very single among sugar beet CMS resources. So some kind of disease pandemic in sugar beet planting is a potential risk. A new type sugar beet cytoplasm（K-5） male sterility material which was found recently in China will be used as experimental materials in this project research, and two research methods of molecular biology technology (primer design,probe sequence design,gene clone expression,molecular detection) and plant breeding process(flower season observation,pollen identification,plant choosing) will be applied in this project. Mechanism of male sterility for the novel cytoplasm and difference of fertility related gene locus in mitochondria between the new type cytoplasm and Owen type cytoplasm, S-2 type, S-3 type cytoplasm will be discussed in this program.we intend to illustrate structural features and function difference as well as RNA edit expression features of cox1,cox2,atp6 and atp9 gene.Anther preferential bHLH transcription factors genes related with CMS in K-5 line will be cloned and its expression feature key to male sterility will be studied.K-5 mitochondria male sterility mechanism will be further explained clearly.This study will provide theoretical foundation for applying the novel cytoplasm germplasm resources.

甜菜属于典型的异交作物。其Owen型细胞质是目前唯一应用于生产甜菜杂交种的细胞质,种质单一,存在着某些病害大流行的风险。本项目拟利用我国甜菜中新发现的新型细胞质（K-5）雄性不育材料为试材,采用分子生物学技术（引物、探针序列设计、基因克隆、分子检测）及作物育种学（花期观察、鉴定、选择）相结合方法开展研究。探讨新型细胞质雄性不育性的机制,寻找新型细胞质线粒体育性相关基因与S(Owen)型、S-2型、S-3型线粒体相关基因的差异。明确新型细胞质K-5线粒体与Owen型雄性不育线粒体不育相关基因的结构特点及功能差异。探明K-5型细胞质线粒体cox1、cox2、atp6、apt9基因结构、RNA编辑、表达翻译特点，克隆K-5型甜菜中与CMS 相关的bHLH蛋白家族中花药优势表达转录因子基因探究其表达特征及对育性的调控,从而进一步明确K-5线粒体雄性不育机制，为新型细胞质种质资源生产利用提供理论依据

甜菜是重要的糖料作物质之一，属于典型的异交作物。由于甜菜花粉器官的特殊结构，大规模去雄很难操作，选育不育系是甜菜应用于农业生产的主要瓶颈技术。Owen型细胞质是目前唯一应用于甜菜生产种的细胞质，种质单一，存在着某些病害大流行的风险。本课题组在进行甜菜种质资源遗传多样性研究中，从收集保存筛选的中国甜菜资源中发现了新的细胞质甜菜，K-5材料群体的指纹标记中发现新的条带,存在特殊细胞质单株个体。. 本项目利用新发现的新型细胞质(K-5)甜菜材料群体为研究对象，采用分子生物学技术（引物、探针序列设计，基因克隆、序列比对分析）及作物育种学（花期观察、育性鉴定、选择）相结合的方法，对新发现的甜菜材料的育性特点、花粉培养、多态性、线粒体上某些基因序列进行了详细分析与研究,并对开花及育性相关的转录子等进行了测试分析，克隆优势表达育性相关转录因子。探明甜菜新型细胞质材料品系及分离后代育性特点，明确新型细胞质线粒体育性相关基因与(Owen)型等线粒体相关基因在某些位点的差异。明确新型线粒体材料中的几种分离品系与Owen型雄性不育线粒体育性相关基因的结构特点及差异。获得新型甜菜材料线粒体某些基因序列标记甜菜育性特点数据。. 经过对亲本及配制的杂交组合后代植株的花期育性的细胞观察结合分子标记鉴定，从材料群体中选育出一对完全不育及其保持系株系，为进一步的甜菜生产利用提供理论依据及育种材料亲本。