苹果优良砧木资源—小金海棠

MALUS XIAOJINENSIS CHENG ET JIANG—A PROMISING STOCK FOR APPLE TREES

小金海棠分布在沿岷江上游和大渡河中上游流域之间 ,称为岷江一大渡河带。该地区有陇东海棠系等 10多种苹果属植物的分布 ,种类间的汇集 ,表现为地理亲缘。不同物种汇集地 ,无疑是物种分化及种质渗入十分活跃的地带 ,而小金海棠则有可能是物种分化及种质渗入形成的多倍体杂种。小金海棠幼苗的叶形与陇东海棠近似 ,其分布区与陇东海棠系表现为地理亲缘 ,因此 ,小金海棠应归属于陇东海棠系。小金海棠是在全球范围内筛选出的第一个抗缺铁黄叶病苹果基因型 ,对潜隐病毒也有较强的抗性 ,是极重要的苹果种质资源。作苹果砧木利用 ,其综合性状优于M7。

Malus xiaojinensis is distributed in Mingjiang-Daduhe Strand,the area stretching from the upper reaches of the Mingjiang River to the middle and upper reaches of the Daduhe River. This area is also inhabited by a dozen species of the genus Malus ,including Ser. kansuensis Rehd. They grow together and show some geographic affinity and are likely to have originated from evolution and introgression. M. xiaojinesis is probably a polyploid hybeid arising from specific differentiation and germplasmic introgression. The shape of its leaves is similar to that of M. kansuensis and its distributing suggests a geographic affinity with Ser.kansuensis indicating that it falls into the series Ser. kansuensis taxonomically. The experiment ducuments available show that M. xiaojinensis is resistant to latent virus and the first apple genotype selected for resistance to Fe deficiency. As a stocks, it performed better than M 7. It is believed that this species is a very promising semi-dwarf stock for apple trees.