关于杨树多倍体育种的几点认识

Some understandings on polyploid breeding of poplars

诸多杨树多倍体实例表明,基于有性多倍化的多倍体育种,可以通过一轮次的育种过程实现杨树多目标性状综合改良,获得生长快、纤维长、木素低、纤维含量高以及抗逆性强等性状表现突出的杨树品种。在具体杨树多倍体育种工作中,掌握配子或合子染色体加倍有效处理时期的即时判别方法,有助于提高杨树多倍体育种效率和效果;而多倍体品种表现优劣与其杂合性密切相关,通过杂交亲本选配以及适宜的配子染色体加倍途径选择等,可以增进多倍体的杂合性,在利用基因剂量效应带来的倍性优势同时,充分利用异源配子结合产生的杂种优势,最大限度地发挥杨树多倍体育种的技术潜力。

Many instances of polyploid poplars indicate that it is probable to achieve multi-objective and integrated improvement of poplars and to produce varieties characterized by fast growth,long fiber length,low content in lignin,high content in fiber and strong adversity resistance through one round of polyploid breeding process based on sexual polyploidization.In practice of polyploid breeding of poplars,it is helpful for increasing the efficiency and effect of polyploid production to master the methods for instant determination of effective treating period of gametic and zygotic chromosome doubling.Furthermore,because phenotype of one polyploid is associated with its heterozygosity,it is important to select suitable parents,mating individuals and approaches for gametic chromosome doubling.Maximization of the heterozygosity in polyploids can carry out advantages of both ploidy vigor from gene dosage effects and heterosis from union of heterologous female and male gametes,leading to maximize the potential of techniques for polyploid breeding of poplars.