Abstract: In order to understand the effects of bark thickness and diameter class on the apple buprestid (Agrilus mali Matsumura ) damage in Xinjiang wild apple varieties, Xinjiang wild apples with different resistance to apple buprestid were taken as plant material to find the relationship between the total number of insect and bark thickness, diameter class by correlation regression method. Results showed that there were big differences in apple buprestid damage severity existing in different wild apple single plant, among them feather hole numbers of XY-101 single plant were as high as 11.2. While that of XY-49 single plant was as low as 0. The total average population ranged from 0.3~11.2, and the differences were very significant. The regression equation between the total number of insect and diameter class, bark thickness were as follows: Y=1.236+0.119Z and Y=1.049+2.071H. Both equations went through the t test at P<0.05 significance level. Regression coefficient of variate Z was 0.119, which meant that when diameter class increased 1 mm, the total number of insect would increase to 0.119. Regression coefficient of variate H was 2.071, which meant that when bark thickness increased 1 mm, the total number of insect would increase to 2.071. Therefore, total number of insect were positively and linearly correlated with bark thickness and diameter class within a certain scope in Xinjiang wild apple. The total number of insects increased with the increasing of bark thickness and diameter class.

Key words: Xinjiang wild apple, Agrilus mali Matsumura, insect resistance, regression analysis

摘要： 为了解新疆野苹果（Malus sieversii）树皮厚度、径阶对苹小吉丁虫危害程度的影响，以具有不同抗苹小吉丁虫(Agrilus mali Matsumura )特性的新疆野苹果类型单株为试验材料，利用相关性回归法找出树皮厚度、径阶与总虫数之间的关系。结果表明：不同野苹果单株受苹小吉丁虫危害差异较大，其中XY-101单株羽化孔数最高11.2个，而XY-49单株最低为0个，总虫口平均数在0.3~11.2头之间，差异均极显著；径阶、树皮厚度分别与总虫数的回归方程为：Y=1.236+0.119Z和Y=1.049+2.071H，在P<0.05显著水平下两个方程均通过了t检验，其中变量Z的回归系数为0.119，即径阶每增加1 mm，总虫数就增加0.119个。变量H的回归系数为2.071，即树皮厚度每增大1 mm，总虫数就相对应增加2.071个。因此，新疆野苹果的径阶、树皮厚度与总虫数在一定范围内呈正相关线性关系，随着树皮厚度、径阶的增大，总虫数也明显增大。

关键词: 新疆野苹果, 苹小吉丁虫, 抗虫性, 回归分析