不同抗性马尾松针叶中营养物质含量与对松突圆蚧抗性关系的判别分析

为了探讨马尾松Pinus massoniana针叶营养物质含量与其对松突圆蚧Hemiberlesia pitysophila Takagi抗性的关系， 选择了不同抗性的10个马尾松家系， 分别测定未受松突圆蚧危害植株与受害植株针叶中可溶性糖、 总糖、 可溶性蛋白、 全N、 游离氨基酸、 粗脂肪等营养物质的含量和总糖/全N等7个指标， 并采用判别分析法分析这7个指标与马尾松家系对松突圆蚧抗性的关系。结果表明：马尾松家系不论是否受松突圆蚧的危害，能明显区别抗性组别的指标都是可溶性蛋白（X₃）、全N（X₄）和游离氨基酸总量（X₇），随抗性的降低， 它们的含量呈上升趋势， 受害植株中上述3个指标的含量低于未受害植株； 受害后， 各指标变化量中能明显区别抗性组别的是全N（X₄）， 随着植株抗性的降低， 针叶中的可溶性蛋白（X₃）、全N（X₄）和游离氨基酸总量（X₇）的含量变化量减小。据此得出：（1）可溶性蛋白（X₃）、全N（X₄）和游离氨基酸总量（X₇）是与抗性关系最密切的指标， 含量与抗性呈负相关关系，变化量与抗性呈正相关关系；（2）受到危害后， 无论含量或变化量， 7个指标都发生了重要变化， 都表现出与抗性的相关性， 构成了有效判别函数的组成变量；（3）因判别分析方法可以分析各指标的综合作用， 应用该方法分析各营养成分与马尾松对松突圆蚧抗性的关系， 比用方差分析和多重比较方法更有优越性。上述研究结果为抗松突圆蚧马尾松家系的选育及其抗性机理的深入研究， 提供了重要的科学参考价值。

Discriminant analysis of the relationship between nutrient contents in needles of Pinus massoniana and its resistance against Hemiberlesia pitysophila(Hemiptera: Diaspididae)

 In order to investigate the relationship between the nutrient contents in needle of Pinus massoniana and its resistance against the pine armoured scale, Hemiberlesia pitysophila, contents of some nutrients were measured, including soluble sugar, total sugar, soluble protein, total N, free amino acids, crude fat and total sugar/total N in the needles of ten pine families both damaged and undamaged by H. pitysophila. Discriminant analysis was applied to analyze the relationship between seven indicators and the resistance of P. massoniana against H. pitysophila. Contents of soluble protein (X₃), total N (X₄) and total free amino acids (X₇) in the pines damaged or undamaged showed significant differences, suggesting they can be used for the indicators to distinguish the resistant group from the susceptible group. The three indicators increased with the decrease of tree resistance. The contents of the three nutrients in damaged pine were all significantly lower than those in undamaged pine. The total N (X₄) was significantly variable in discrimination of the resistance levels. The variation of soluble protein (X₃), total N (X₄) and total free amino acids (X₇) in the damaged pines all decreased while the resistance decreased. It is concluded that soluble protein (X₃), total N (X₄) and total free amino acids (X₇) might be the most important resistance indices. These indices and their variation have significantly negative and positive correlation with the tree’s resistance against H. pitysophila, respectively. The all seven indicators and their variation changed while the pine needles were injured, showing a correlation between the resistance and construction of the variable of effective discriminant functions. Compared with multiple comparisons and analysis of variance, the discriminant analysis seems more comprehensive and scientific for multi-target, multi-object and multi-group analysis.