伞房属4个树种/亚种在广东德庆的早期生长表现

本文分析了引自澳大利亚东部的桃金娘科伞房属4个树种或亚种在广东省德庆试验点的早期生长表现。结果表明：10年生时,4个树种或亚种生长量最大的是斑皮柠檬桉,其次是大叶斑皮桉(Corymbia henryi)、柠檬桉和斑皮桉,平均单株材积分别为0.2026、0.1748、0.1634和0.0526 m3;与8年生时比较,4个树种或亚种在10年生时仍保持较快的增长速度,材积增长均在15%以上。方差分析结果表明：试验组Ⅰ内,柠檬桉和大叶斑皮桉3个生长性状在家系间差异极显著(P＜0.01);种源间胸径差异达显著水平(P＜0.05),树高和单株材积无显著差异;在试验组Ⅱ,斑皮柠檬桉和斑皮桉的3个生长性状在树种或亚种、种源、家系间差异极显著(P＜0.01)。以单株材积高于对照为选择目标,选出柠檬桉3个种源4个家系,斑皮柠檬桉4个种源11个家系,大叶斑皮桉2个种源3个家系,共计9个种源18个家系,分别占参试种源和家系总数的50%和19.4%。

Early Growth Performance of Four Corymbia Species in Deqing County

Early growth performance of four species of the Corymbia genus from eastern Australia was studied. Average increments to ages eight and ten years in Deqing, Guangdong province, were analyzed and provenance and family selection was carried out based on growth traits at age ten years. The best species was C. variegata, followed in order by C. henryi, C. citriodora and C. maculata. The average single-tree volumes of the four species were 0.203, 0.175, 0.163 and 0.053 m3, respectively. All four species maintained fast growth rates up to age 10 years, and the volume increment per annum at age 10 years was over 15%. Analyses of variance for growth traits showed that the height, diameter at breast height (DBH) and single-tree volume of C. henryi and C. citriodora were similar, and that within these two species there were highly significant differences among families for DBH and single tree volume, and there were significant differences among provenances for DBH whilst differences among provenances for height and the single-tree volume were not significant. For the other two species, C. variegata and C. maculata, differences among species/subspecies, provenances and families were highly significant for all growth traits. Nine provenances and eighteen families were selected based on having significantly higher than average single-tree volumes compared to the CK, accounting for 50.0% of all provenances and 19.4% of all families, respectively.