毛新杨×毛白杨［（Ｐｏｐｕｌｕｓｔｏｍｅｎｔｏｓａ×Ｐ．ｂｏｌｅａｎａ）×Ｐ．ｔｏｍｅｎｔｏｓａ］异源三倍体无性系综合形态特征为偏毛白杨，部分近于新疆杨（如长枝叶），只有长枝叶、雄花序等表现出了较明显的巨大性．其花粉母细胞减数分裂进程较毛白杨、毛新杨约快８～１２ｈ，且极不同步．三倍体染色体联会和分离的行为复杂，在中期Ⅰ除了出现三价体、二价体、单价体外，还可见到四价体和五价体；在后期Ⅰ、后期Ⅱ亦可见到较高频率的落后染色体，遗传上属于部分异源三倍体．这些毛白杨异源三倍体表现高度不育，但存在着无性系差异．花粉部分可育三倍体（Ｂ３０２）的存在，为相关的遗传分析及倍性育种实践提供了极其有用的材料 Mao Yang Yang × Populus [Populustomentosa × P. boleana) × P. tomentosa] The morphological characteristics of allotriploid clonal hybrids are Populus tomentosa, part of which are close to Xinjiang poplar (long branches and leaves), and only the long branches and leaves, male inflorescence showed obvious obviousness. The pollen mother cell meiosis process more than poplar, Mao Yang new about 8 ~ 12h, and very not synchronized. Triploid chromosome association and separation behavior complex, in addition to the emergence of trivalent, bivalent, monovalent in vitro, but also can see the tetravalent and pentavalent body; in the late I, late Ⅱ can be seen higher The frequency of backward chromosomes, genetically belong to part of the allotraploid. These Populus tomentosa hybrids are highly sterile, but have clonal differences. The presence of pollen-partially fertile triploids (B302) provides an extremely useful material for related genetic analysis and ploid breeding practices