【摘要】 利用环境扫描电镜观察了苹果属17个原生种和25个观赏海棠品种的花粉形态特征,采用类平均法(UPGMA)进行聚类分析,探讨其花粉的主要特征及差异,研究了亲缘关系及类群。结果表明,苹果属植物花粉为N3P4C5型,呈两侧对称的长球形或超长球形,赤道面具3条孔沟,沿极轴方向延伸至两极,萌发沟内有内孔,花粉表面为条状纹饰,有穿孔;各种或品种间花粉粒大小及外壁纹饰差异明显。聚类分析表明,佛罗伦萨海棠等2个苹果属原生种以及‘罗宾逊’等7个观赏海棠品种聚为第一类群;山荆子等9个苹果属原生种以及‘霍巴’等3个观赏海棠品种聚为第二类群;赛威士苹果等4个苹果属原生种以及‘道格’1个观赏海棠品种聚为第三类群;野香海棠等2个苹果属原生种以及‘凯尔斯’等14个观赏海棠品种聚为第四类群。25个观赏海棠品种起源于北美洲基因中心,并通过与欧洲、亚洲基因中心的苹果种间杂交形成亲缘关系复杂的品种。更多还原

【Abstract】 Pollen morphology of 17 original Malus species and 25 ornamental crabapple cultivars were observed using environment scanning electron microscope.The results indicated that the apple pollen belonged to the N3P4C5 type,bilateral symmetry,prolate sphericity or ultra prolate sphericity,with three germinal furrows extending almost to the full length of the grain.The exine surface had a striate pattern and some small pores.From the UPGMA cluster analysis,the 42 taxa could be classified into four groups.The first group contained M.florentina,M.sylvestri,M.’Robinson’ and other 6 cultivars.The second group included M.baccata and other 8 species and 3 crabapple cultivars,like M.’Hopa’.The third group consisted of M.sieversii and 3 more species and cultivar M.’Dolgo’.The last group comprised of M.coronaria,M.platycarpa,M.’Kelsey’ and 13 more crabapple cultivars.Twenty-five ornamental crabapple cultivars originated from a very complicated genetic complex,which could be stated as cross-hybrids from species from North America,Europe,and Asia.更多还原