白榆是我国平原地区重要的用材树种.分布广、栽培历史悠久。据调查,任新乡地区白榆总株数达4743万株,占全区林木总株数的51%,在孟县、温县、武陟、获嘉等县,白榆占四旁树的70%以上,因而被誊为“白榆之乡”。但在长期的栽培实践中,利用的是天然群体,干低、干弯、生长慢、病虫严重。急需进行遗传改良,提高其经济和 White elm is an important timber species in the plain of our country, which has a wide distribution and a long history of cultivation. According to the survey, the total number of white elm in Ren Xinxiang reached 47.43 million, accounting for 51% of the total number of trees in the region. In Mengxian County, Wenshen County, Wuhu County and Huaxia County, white elm accounted for more than 70% Thus 誊 as “elm township ”. However, in long-term cultivation practice, the use of natural populations, dry low, dry bend, slow growth, serious pests. Urgent need for genetic improvement, improve their economy and