1972 金花苔（原始不育株） 48A X 金花苔（何育株） 48B ⑧ 48A(不育株率62.5%) ×金花苔48B 1973 F (选不育株率高的株系回交) 、⑧ 48A(不育株率71.7%) BC 金花苔48B 1974 (选全不育的株系回交，其余淘汰) 、图 48A(不育株率88.9%) BC2 金花苔48B 1975 (选全不育的株系回交，其余淘汰) ⑧ 48A(不育株率94.5%) BC3 金花苔48B 1976 (选全不育的株系回交，其余海汰) ⑧ 48A(不育株率稳定在95%以上) 金花苔48B×金花苔48B 1977 (选全不育的株系回交，其余淘汰) 不育系 保特系 4) 金花苔不育系和保持系选育过程 Chapter 5 Self-incompatibility Self-incompatibility denotes the inability of a plant to set seeds upon self-pollination, despite the fact that both ovule and pollen development are normal and viable.This is due to some physiological hindrance to fertilization,for example slow pollen tube growth.Self-incompatibility differs from male sterility. The important differences are given in Table 5.1 Table 5.1 Differences between male sterility and self-incompatibility Male sterility self-incompatibility 1.Due to failure of processes such as pollen Due to some physiological hindrance to development fertilization.Failure to obtain seeds is due to slow pollen tube growth. 2.Pollen are non-functional(abortive) Pollen and ovule are normal and functional. 3.Genetic,cytoplasmic or both cytoplasmic Genetic and physiological factors and genetic factors control the expression of control the expression of male sterility self-incompatibility 1.Systems of Self-incompatibility Factors such as genetics,physiology and floral morphology determine the system of self-incompatibility. 1616 4) 金花苔不育系和保持系选育过程 Chapter 5 Self-incompatibility Self-incompatibility denotes the inability of a plant to set seeds upon self-pollination, despite the fact that both ovule and pollen development are normal and viable. This is due to some physiological hindrance to fertilization, for example slow pollen tube growth.Self-incompatibility differs from male sterility. The important differences are given in Table 5.1 Table 5.1 Differences between male sterility and self-incompatibility Male sterility self-incompatibility 1.Due to failure of processes such as pollen development 2.Pollen are non-functional(abortive) 3.Genetic,cytoplasmic or both cytoplasmic and genetic factors control the expression of male sterility Due to some physiological hindrance to fertilization. Failure to obtain seeds is due to slow pollen tube growth. Pollen and ovule are normal and functional. Genetic and physiological factors control the expression of self-incompatibility 1.Systems of Self-incompatibility Factors such as genetics, physiology and floral morphology determine the system of self-incompatibility