monosomic

(2) it was difficult to obtain alien disomic addition lines from alien monosomic and double monosomic additions;

(2)在建立小-二体附加系的研究中，体和双体附加系并非好的基础材料；

(2)在建立小-二体附加系的研究中，体和双体附加系并非好的基础材料；

(2) it was difficult to obtain alien disomic addition lines from alien monosomic and double monosomic additions;