1.退化原因 (1)长期的无性繁殖是引起大蒜退化的内在因素。一般来说,生物界通常是经过有性繁殖才能产生生命力强的后代,而大蒜在生长发育过程中,没有经过有性杂交,也不能产生具有较强生命力的种子。作为播种材料的蒜瓣,是大蒜母体的组成部分,大蒜的生育周期只能是从蒜瓣到蒜瓣。如此下去,不论繁殖多少代,依然是同一世代,所以,大蒜品种的退化现象是长期无性繁殖的必然结果。 (2)大蒜病毒病是世界性的普遍感染的病害,是导致大蒜种性退化,产量降低的重要原因。我省大蒜退化 1. Degradation causes (1) Long-term clonal propagation is the internal factor that causes garlic degradation. In general, the biological world is usually after sexual reproduction to produce strong offspring, and garlic in the process of growth and development, no sexual hybridization, can not produce a strong vitality of the seeds. Garlic clove as sowing material is an integral part of the garlic matrix. The growth cycle of garlic can only be from garlic cloves to garlic cloves. So go on, no matter how many generations of reproduction, is still the same generation, so the phenomenon of degradation of garlic varieties is the inevitable result of long-term asexual reproduction. (2) Garlic virus disease is a worldwide disease of common infection, and is an important reason for the degeneration of garlic and the decrease of yield. Garlic degradation in our province