甘薯属高温短日照作物,在温带地区一般不能自然开花。进行有性杂交育种必须预先诱导开花,其开花迟早和数量,固属品种特性,但也受温光等条件的影响。而且,由于品种间杂交亲和力有异,不同组合的结蒴率相差很大;即使组合相同,不同季节的气温条件对结蒴 Ipomoea high-temperature short-day crops, temperate areas in general not natural flowering. For sexual hybrid breeding must be pre-induced flowering, the flowering sooner or later, the number of solid species characteristics, but also by temperature and other conditions. Moreover, due to differences in hybridization between varieties of different combinations of the junction of the bolt rate vary greatly; even if the combination of the same season, the temperature conditions of the knot capsule