马尾松半同胞子代苗期与幼林生长变异分析及家系选择

为探讨马尾松改良种子园半同胞家系子代的生长变异情况，测定分析了26个家系1 年生苗高、地径和0.5年生、1.5 年生及2.5 年生幼林的树高、地径、胸径、材积和冠幅等生长指标。结果表明，各性状在家系间均存在极显著差异，参试群体的树高、胸径、材积和冠幅的家系遗传力大于0.8，且前三个性状的单株遗传力大于0.4，说明上述性状是遗传力较高的性状。2.5年生材积生长量显著高于普通生产种的优良家系有19个，入选率为73%，树高、胸径和材积的遗传增益分别为2.76%、3.60%和8.49%，与初级种子园混合种和普通生产种相比，其材积分别提高55.28%和218.28%。

Variation Analysis and Family Selection on Half-sib Progenies of Pinus massoniana

To understand variation of growth traits of height(HT), diameter at breast height(DBH), volume of individual tree (VOL) and crown width(CW), 26 half-sib progenies from improved seed orchard of masson pines were planted at Xinyi. Investigation was conducted at 0.5, 1.5, and 2.5 years-old pines to study inheritance and early selection efficiency for HT, DBH, VOL and CW. The results showed that every trait studied had significant differences among families. Heritability of HT, DBH, VOL and CW was higher than 0.8, individual heritability of HT, DBH and VOL were higher than 0.4. 19 superior families were selected out under the selection ratio of 73% with the genetic gain of HT, DBH and VOL of 2.76%, 3.60% and 8.49% respectively, and VOL of 19 superior families was 55.28% higher than the primary seed orchard cultivar and 218.28% higher than common varieties.