桉树多树种无性系在川南地区生长比较

为选择出适合在川南地区造林的桉树无性系，对17个桉树新无性系在川南地区的宜宾市进行了造林对比试验。结果表明：以 SC-GU2、SC-GU1和 GR-6三个无性系生长表现好，4年生的胸径、树高、单株材积和蓄积均高于对照 DH32-29，其中单株材积分别比 DH32-29高出9.51%、4.53%和4.94%；其次是 G5，在川南地区也生长较好，生长量仅次于 DH32-29。4个桉树无性系 SC-GU2、SC-GU1、GR-6、G5的胸径、树高、单株材积和蓄积均均极显著高于5个赤桉无性系(H1,、H2,、H3、 H4和 H10)，年均胸径、树高、蓄积分别达3 cm、4 m、31.72 m3·hm-2以上，表现了速生丰产的特性，可作为下一批优良桉树无性系在川南地区推广造林。

Growth Variation of Eucalyptus Clones in Southern Sichuan

A clonal plantation field trial was conducted between seventeen Eucalyptus clones in order to select superior Eucalyptus clones for plantation establishment in southern Sichuan. Growth of the clones at age 4-years showed that: three clones SC-GU2, SC-GU1 and GR-6 had the best growth; diameter at breast height (DBH), tree height and volume increment of these three clones were higher than DH32-29; and, compared with DH32-29, the volume increment of the three clones were 9.5%, 4.5% and 4.9% greater respectively than that of DH32-29. A fourth clone, G5, also grew well in southern Sichuan, and was slightly better than DH32-29. The annual average increments for DBH, tree height and volume per hectare were over 3 cm, 4 m and 31.72 m3·hm-2 respectively, and these four clones all had significantly higher growth than five Eucalyptus camaldulensis clones (H1, H2, H3, H4, H10) included in the trial. From the trial it was concluded the four superior clones showed the characteristics of fast growing and high yielding varieties and they will be suitable for deployment in commercial plantations in southern Sichuan.