对苹果属植物２２个种类进行自交和种间杂交表明，大多数种类自交不亲和，种间易于杂交，但其杂交亲和程度各异，有同系不同种间＞系间＞组间的趋势。金县山荆子与山荆子亲缘关系极远，不一定是山荆子的变种。毛山荆子与湖北海棠、小金海棠与马尔康海棠的亲缘关系极近。珠眉海棠可能是山荆子和三叶海棠的杂交种。 Inbred and interspecific hybridization of 22 species of apple genus showed that most of the species were self-incompatible and interspecific hybrids were easy to cross, but their hybridization affinity were different, the trend of. Jinxian Shan Jing Zi and Shan Jing Zi kinship far-reaching, may not be a variant of Shan Jing Zi. Maoshan Jing and Hubei Begonia, Begonia and Malcolm Begonia very close genetic relationship. Begonia Begonia may be a cross between a mountain tree and a cauliflower.