水肥胁迫对尾叶桉无性系生长及叶片变异的影响研究

为选择尾叶桉(Eucalyptus urophylla)优良无性系,以20个尾叶桉无性系为材料,采用2因素(水分、养分)3水平完全随机区组设计,对水肥胁迫半年后尾叶桉苗木生长和叶片性状变异进行分析和评估。结果表明,尾叶桉的叶尖角、叶长、叶宽、叶周长和叶面积在不同水肥处理下差异显著,表明水分和养分会影响叶片的大小。苗木生长和叶片性状间大多数呈显著或极显著正相关,少数呈显著负相关或一定的负相关性。13种性状可综合为4个主成分,其累计贡献率达98%,说明这些性状具有极强的代表性。除地径的水分×养分互作不显著外,生长性状在水分、养分及水分×养分互作上达显著和极显著的水平。无性系在树高、地径和冠幅上的方差分量为2.19~149.59,重复力为0.16~0.45。以20%入选率,采用基因型值筛选出4个优良无性系:LDUA10、ZQUA9、ZQUA8和LDUA24,他们的树高、地径和冠幅比对照分别高出5.0%、12.8%和14.5%,为后续骨干亲本选择及优良无性系推广提供依据。

Effects of Water and Nutrient Stresses on Growth and Leaf Variation of Eucalyptus urophylla Clones

In order to select excellent clones of Eucalyptus urophylla, the growth and leaf characters of 20 clones in half-year-old under water and nutrient stresses were analyzed and evaluated by using a randomized complete block design according two factors and three levels. The results showed that leaf apex angle (LBA), leaf length (LL), leaf width (LW), leaf perimeter (LP) and leaf area (LA) had significant differences among water and nutrient treatments, indicated that water and nutrient had influence on the leaf size. There were significant positive correlations between most of growth and leaf characters, and a few showed significantly negative correlations. The principal components analysis showed that the cumulative contribution rate of the first four principal components accounted for 98%, indicating that they had strong representativeness. Growth traits under water, nutrient, water×nutrient interaction reached a significant level except for ground diameter (GD) under water × nutrient interaction. The component variance for H, GD and CW ranged from 2.19 to 149.59, and repeatability ranged from 0.16 to 0.45. The four excellent clones, such as LDUA10, ZQUA9, ZQUA8 and LDUA24, were selected according to 20% selected ratio and genotypic value, and the H, GD and CW of four clones was 5.0%, 12.8% and 14.5% higher than control, which would provide basis for further selection and extension of superior clones.