关键词: 胡杨, 负向演替, 良种选育, 无性繁殖, 人工林

Abstract: Populus euphratica Oliv.is in its declining stage of negative succession in Gansu Province.There are 73 0% declining and mature forest which grow sparsely,5% young forest less than 15 years and rare seedings between 1 and 5 years in the 14 590 hm² populus forest.The main restrictive factors of development lie in both the deterioration of water-soil environment and the disadvantages in artificial forest resulted from the difficult propagation and not uniform seedlings of Populus euphratica Oliv.The development strategies of P.euphratica.had been suggested that only with the combination of successive vegetative propagation and breeding desirable varieties,afforestation with improved varieties in a large scale could be practical.

Key words: Pouplus euphratica Oliv., Negative succession, Vegetative propagation, Breed selection, Artificial forest