杨树抗寒抗旱育种的进展

系统地回顾了国内外杨树抗寒抗旱育种的成果和进展。可得出以下结论：（１）杨树抗寒抗旱性改良基本上有两个途径：即选择天然杂种和进行人工杂交育种，而且人工杂交的育种成果远远多于选择随机存在的天然抗寒抗旱杂种。（２）白杨派树种的研究和进展远远落后于青杨及黑杨派树种。主要表现在杂交方式简单，以单交方式为主；选用的亲本有银白杨、新疆杨和山杨；在青杨及黑杨派树种的改良中，小叶杨是一个很好的抗寒抗旱亲本；（３）在杂交方式上由简单到复杂、从单交到多交（三交、四交），抗寒抗旱改良和综合改良的效果随着杂交方式的不断复杂而愈来愈好。同时认为：在遗传工程、生物技术蓬勃发展的今天，杂交育种这一古老的方法仍是杨树抗寒抗旱育种最有效和最基本的手段；在已有的抗寒抗旱种质资源基础上，采用杂种作亲本，进行更复杂的杂交方式是创造杨树抗寒抗旱品种的一个重要方向

Progress in Cold- and Drought-resistant Breeding of Poplars

Poplars are generally planted in many countries,and the cold and drought-resistant breeding is a very important field in poplar improvement and culture.Achievements and progress in this field in China and other countries are systematically reviewed.Although the genetic engineering and the biotechnology have been quickly developed today,the cross breeding,a traditional method,has still been the most effective and essential approach. It would be a promising way to do complicated cross patterns using available hybrids as parents.