桃是我国北方果树的主栽树种之一，仅河北省栽培面积就达130万亩，由于河北省所处地理位置的原因（桃树栽培北限），桃树冻害频繁发生，且具有规律性，给桃生产带来极大的影响。培育抗寒性品种成为桃树育种的主要目标之一，而桃树抗寒性机理的研究就成为育种学家关注的重要科学问题。本课题组长期从事桃育种工作，从2003年起，以抗寒品种（大久保桃）、不抗寒品种（21世纪桃）为亲本，分别进行了正交（大久保桃×21世纪桃）、反交（21世纪桃×大久保桃）试验。在寒害发生时，正交与反交两个组合在F1代的抗寒程度的加权平均值具有显著差异（冻害指数1.25/2.55），这意味着抗寒性状除了细胞核基因控制以外，细胞质基因也发挥着重要的作用，即细胞质遗传（或母性遗传），本项目拟通过对细胞质基因组的基因组学和蛋白组学的研究，揭示桃抗寒性与细胞质基因的内在关系，为果树细胞质基因与抗寒性的研究提供重要的理论支持。

Peach is one of the main cultivated fruit trees in northern China, cultivated area of which reached to 130 million mu in Hebei Province. Due to the geographical location, the stable and high yield of peach was influenced frequently by the freezing injury with regularity, leading serious impact on the peach's production. Breeding cold resistant variety has to become one of the main goals of peach breeding, and the mechanism study of cold resistance of peach has become an important scientific problem for breeders . In order to solve this problem,crossbreeding combinations between cold resistant varieties and not cold resistant varieties was performed respectively from 2003 . When chilling injury occurs, the orthogonal and back crossing combinations of two group in F1 generation has significant differences (freezing index 1.25/2.55), which means that the cold resistent is associated with cytoplasmic genes in addition to nuclear genes. namely the cytoplasmic inheritance (or maternal inheritance). This the project intends to study onStudy on cytoplasmic genome genomics and proteomics, revealing the inner relationship between cold resistent and cytoplasmic genes in peach， Which would support the important theory for cold resistent in furit tree.