Investigation of chromosome numbers of cultivars and four cultivated species of Mains in China

摘要

Chromosome numbers of 50 cultivars, 9 types, and 4 cultivated species of Malus in China were studies by wall degradation hypotonic treatment method. It was found that M. pumila Mill., M. domestica subsp. chinensis Li., and M. prunifolia Borkh. have two ploidies which are diploid (2n=2x=34) and triploid (2n=3x=51); M. asiatica Nakai has three ploidies which are diploid (2n=2x=34), triploid (2n=3x=51), and tetraploid (2n=4x=68). It was first found that 'Xiangguo', 'Yuanxiangguo', and 'Hushalai' of M. domestica subsp. chinensis Li. are triploids (2n=3x=51); 'Daqiuguo', 'Hongnaizi', 'Huangnaizi', and 'Huangtaiping' of M. prunifolia Borkh. are triploids (2n=3x=51); 'Matinaizi' and 'Xiangbinri' of M, asiatica Nakai are triploids (2n=3x=51); 'Miguo', 'Huangtianguo', and 'Dashaguo' of M. asiatica Nakai are tetraploids (2n=4x=68). It has been proved that 'Jonagold', 'Stayman Winesap', and 'New Jonagold' of M. pumila Mill, are triploids (2n=3x=51). The other cultivars are all diploids (2n=2x=34).