【目的】 明确西伯利亚龟象Rhinoncus sibiricus 的为害与荞麦不同品种叶片生化物质含量及防御酶活性的关系，为选育荞麦抗虫品种和该虫的综合治理提供科学依据。【方法】 采用五点取样法对西伯利亚龟象在荞麦田中的为害情况进行调查；在室内条件下，观察西伯利亚龟象对4种（蒙0208、蒙0207、晋苦6和晋苦2）不同抗虫品种的荞麦的取食选择性，同时测定不同品种荞麦叶片主要营养物质和次生代谢物质的含量、防御酶及蛋白酶抑制剂的活性。【结果】 西伯利亚龟象在蒙0208和晋苦2上的蛀茎率较高，分别为59.22%和65.23%，而在蒙0207和晋苦6上的蛀茎率较低，为47.21%和49.61%。西伯利亚龟象对荞麦不同品种的取食选择顺序为：晋苦2 >蒙0208 >晋苦6 >蒙0207。荞麦抗虫品种的可溶性蛋白、可溶性糖、脯氨酸、类黄酮和总酚含量均显著低于感虫品种（P<0.05），经Pearson相关性分析，西伯利亚龟象对不同荞麦品种的为害选择与叶片中可溶性蛋白（R=0.840）、可溶性糖（R=0.883）、脯氨酸（R=0.750）、类黄酮（R=0.809）和总酚（R=0.729）含量显著正相关。荞麦抗虫品种的苯丙氨酸解氨酶、过氧化氢酶、胰蛋白酶抑制剂和胰凝乳蛋白酶抑制剂的活性均显著高于感虫品种（P<0.05），经Pearson相关性分析，西伯利亚龟象对不同荞麦品种的为害选择与荞麦叶片中苯丙氨酸解氨酶（R=﹣0.837）、过氧化氢酶（R=﹣0.548）、胰蛋白酶抑制剂（R=﹣0.579）和胰凝乳蛋白酶抑制剂（R=﹣0.797）的活性显著负相关。       【结论】 在供试的4个荞麦品种中，蒙0207和晋苦6具有较高的抗虫性，而西伯利亚龟象更偏好取食蒙0208和晋苦2。西伯利亚龟象对不同荞麦品种表现出的抗性与荞麦叶片营养物质和次生代谢物质含量、防御酶以及蛋白酶抑制剂活性等密切相关。

[Objectives]  To investigate the relationship between the damage caused by Rhinoncus sibiricus, the amounts of certain biochemical substances in the leaves of different buckwheat varieties and defensive enzyme activity, in order to provide information for selecting pest-resistant varieties of buckwheat. [Methods]  The damage caused by R. sibiricus to buckwheat was investigate using the five-point sampling method in the field. The relative preference of R. sibiricus for four different buckwheat varieties (Meng 0208, Meng 0207, Jinku 6, Jinku 2) was determined in laboratory experiments. The amounts of major nutrients and secondary metabolites, and defense enzyme and protease inhibitor activity, in the leaves of different buckwheat varieties, were also determined. [Results]  Stem-damage rates on the Meng0208 and Jinku2 buckwheat varieties were 59.22% and 65.23%, respectively; higher than on Meng0207 and Jinku6, which were 47.21% and 49.61%, respectively. The relative preference of R. sibiricus for different buckwheat varieties was: Jinku2>Meng0208>Jinku6>Meng0207. The amounts of soluble protein, soluble sugar, proline, flavonoids and total phenol in insect-resistant buckwheat varieties were significantly lower than in insect-sensitive varieties (P<0.05). There was a significant, positive correlation between the relative preference of R. sibiricus for different buckwheat varieties and the amount of soluble protein (R=0.840), soluble sugar (R=0.883), proline (R=0.750), flavonoids (R=0.809) and total phenol (R=0.729) in leaves. The activities of phenylalanine aminolase, catalase, trypsin inhibitor and chymotrypsin inhibitor were significantly higher in insect-resistant buckwheat varieties than in insect-sensitive varieties (P<0.05). There was a significant, negative correlation between the feeding preferences of R. sibiricus for different buckwheat varieties and the activities of phenylalanine aminolase (R=﹣0.837), catalase (R=﹣0.548), trypsin inhibitor (R=﹣0.579) and pancreatic protease inhibitor (R=﹣0.797) in buckwheat leaves. [Conclusion]  R. sibiricus significantly preferred feeding on the leaves of Meng0208 and JinKu2, whereas Meng0207 and Jinku6 had the highest insect resistance respectively among the four buckwheat varieties tested. The palatability of different buckwheat varieties to R. sibiricus was closely related to their nutrient content, secondary metabolic substances, defense enzyme activity and protease inhibitor activity.