Growth determination and selection of introduced Populus nigre clones in seedling stage

Growth character of 59 Populus nigre clone in seedling stage is determined.Results show that seedling height and collar diameter among clones has significant correlation,and plentiful base of genetic variation.Parameter estimation of quantitative inheritance showed,broad heritability of seedling height of clones is 84.79%,genetic variation coefficient is 10.55%,broad heritability of collar diameter is 79.22%,genetic variation coefficient is 11.8%.13 Clones of PN is selected by method of comprehensive multi-character evaluation,when seedling height and growth quantity of collar diameter are viewed as indice.The genetic gain of seedling height is 12.3%,and 12.2% of collar diameter. The behaviors of N8,N51,and N48 are prominent and their synthetic determination exceeds or approaches the reference species,P.euramericana.If the above 3 clones are selected the genetic gain of seedling height will reach 18.5%,and 23.5% of collar diameter.