随着张掖国家级玉米杂交制种基地的建立,国内外大型种子企业纷纷落户张掖,玉米制种产业也随之成为张掖农民增收致富的支柱性产业。很多种子企业为了保证当年制种亲本的质量和数量,往往会委托当地合作公司为其繁殖大田用玉米自交系,为了保证玉米自交系的质量,就需要在该自交系的繁殖过程中时刻注意防杂保纯工作。玉米亲本自交系的混杂和退化及其表现一个优良的玉米自交系在生产过程中,往往会由于多种原因而发生混杂、退化,丧失了其原有的特征特 With the establishment of Zhangye’s state-level maize hybrid seed production base, large-scale domestic and foreign seed enterprises have set up Zhangye one after another, and the seed production industry of maize has also become a pillar industry for increasing income of farmers in Zhangye. Many seed companies often entrust local cooperative companies to breed maize inbred lines in order to ensure the quality and quantity of their progeny parents. In order to ensure the quality of maize inbred lines, Always pay attention to prevent miscellaneous pure work. Hybridization and Degradation of Maize Parental Inbreds and Their Performance An elite maize inbred line tends to be mixed, degenerated and lost its original characteristics during production