火炬松自由授粉子代测定研究*

对４７个火炬松自由授粉家系进行了苗期和幼林测定。结果表明，家系间苗木保存率与高均差异显著，保存率与苗高呈正相关，但与幼树高生长不相关。家系间树高生长差异显著，有１／５以上明显优良，此外，还研究了统计分析方法与比较标准对选择效果的影响，以及苗期低强度淘汰的有效性。

Research on Open-pollination Progeny Test in Loblolly Pine(Pinus taeda)

An investigation was made on the seedling and juvenile stage of 47 open-polli-nation families in Pinus taeda L.. The results show that the variance of preservation percentand height of seedling between the families are significant. The perservation percent is corre-lated with seedling height, but the seedling height growth is not correlated with saplingheight growth.The differences of height growth between families are significant.There isover 1/5 of the 47 families superior in height growth.In addition,the influence of statisticanalysis method and selection critirion on selection effect were studied,effectiveness of elimi-nation of inferior seedlings was also investigated.