应用指数选择法的原理,以林分的胸径、树高作数量指标,冠长与树高比、胸径与枝基径比为质量指标,对大小兴安岭的兴安落叶松天然优良林分进行了分级。在此基础上,划分了种子林。并对种子品质和子代林进行了测定,结果优良林分种子比一般林分千粒重大3.79～7.99%,发芽率高7.57～9.73%,活力指数高17.24～29.03%,5年生子代林树高育种增益7.35%。 Based on the principle of index selection, the natural stands of Larix gmelinii were classified according to the diameter at breast height, height of tree stand, crown length and tree height ratio, diameter at breast diameter and diameter at branch and shoot. . On this basis, the division of the seed forest. The seed quality and offspring of seedlings were determined. The results showed that the superior stand seed was 3.79-7.99% higher than the general stand, germination rate was 7.57-9.73%, and the vigor index was 17.24-29.3% 7.35%.