火炬松建园无性系球果产量研究

STUDIES ON CLONAL CONE YIELD OF ESTABLISHMENT SEED ORCHARD IN LOBLOLLY PINE

对火炬松８～１２年生的２２７个无性系的球果结实量，连续作了３年观察分析，结果表明，无性系间、年度间差异显著或极显著；多数无性系结果量偏低；对无性系产果量再选择建成的高一级种子园与供选群体相比，增产达８５％～１３７％，甚至更高。按球果丰歉波动状态可划为６种类型，其中以“Ｖ”

Two hundred and twenty seven 8 to 12 years old clones of loblolly pine were three years continuously for their cone yield. The results showed that there were significant differences between clones and between years at 5% or 1% level .Most of the clone obcerved produced low cone yield. Re-selection by cone yield provided high gain. When the high cone yield clones were re-selected to establish advanced seed orchard, the gain of cone yield could be 85%～137% or higher. The clones could be grouped into six types according to bumper or few seed year during these three years. Clones of type 'v' accounted for the largest proportion.