杉木苗期抗寒性的遗传变异和家系选择

近20年来,我国杉木遗传改良工作进展很快,但杉木育种目标多局限于速生丰产,过于单一。目前杉木的栽培区域不断从中心产区向边缘产区扩展延伸,出现了对不良气候、土壤条件的适应性问题。例如,1987年冬浙江各地苗圃遭受早霜冻害十分严重,使上百万株杉苗

GENETIC VARIATION AND FAMILY SELECTION ON COLD HARDINESS OF CHINESE FIR SEEDLINGS

Seeds selected from 73 Chinese Fir families in ten provinces or regions were tested at Fuyang of Zhejiang and Yantai of Shandong for investigation on cold hardiness of Chinese Fir seedlings and selection of the families with cold resistance. The results are as follows: (1) Variations in the rates of freeze and terminal bud, and height of seedlings were very significant among families, and it was found that there were evident interactions between the two experimental sites on the three traits. There was a high negative genetics correlation between the rates of freeze injury and terminal bud, and both characters were slightly corrlated with the height growth of seedlings. (2) There were evident variations in the rates of freeze injury and terminal bud among zones, in which the rate of freeze injury was gradually reduced from the south to the north, whereas the rate of terminal bud was to the contrary; the genetic variance component of provenances outweighed that of families within provenances in the two properties. (3) There was a comparatively high heritability in the rates of freeze injury and terminal bud of seedlings. (4) By means of selecting the rates of freeze injury and terminal bud, 15 families with better cold hardiness were obtained, which mostly came from the north of central subtropical zone.