以江苏省薄壳山核桃〔Carya illinoinensis (Wangenh.) K. Koch〕重点林木良种基地内的42个品种和70份实生单株为供试样本，对10个果实性状和种仁脂肪酸含量进行测定和多样性分析。结果表明：10个果实性状的变异系数为2.86%~32.59%，其中单个坚果种仁质量变异系数最高，其次是单个坚果质量（28.83%）。在供试的112份薄壳山核桃样本种仁中检测到15种脂肪酸，其中，油酸含量（252.485 mg·g^-1）最高，其次是亚油酸（133.952 mg·g^-1）；不饱和脂肪酸含量为396.105 mg·g^-1，占总脂肪酸含量的93.528%，且单不饱和脂肪酸含量（254.919 mg·g^-1）高于多不饱和脂肪酸含量（141.185 mg·g^-1）。15种脂肪酸含量的变异系数为3.145%~57.143%，其中，十四烷酸含量的变异系数最大，十七酸、花生酸、棕榈油酸和亚麻酸含量的变异系数也较大，都在30%以上。相关性分析结果表明：单个坚果质量、坚果横径、坚果纵径和坚果侧径两两之间存在极显著正相关关系；15种脂肪酸含量间大多存在显著或极显著正相关关系。聚类分析结果表明：根据10个果实性状可将供试的112份薄壳山核桃样本分为10组，其中Ⅰ组出油率最高，Ⅶ组果壳最薄、出仁率最高，Ⅸ组坚果较大；根据种仁15种脂肪酸含量可将供试的112份薄壳山核桃样本分为4组，其中A组绝大多数脂肪酸含量最高。综合分析认为供试的112份薄壳山核桃样本果实性状和种仁脂肪酸含量具有较高的多样性，其中SD49和‘Pawnee’种仁脂肪酸含量最高，可作为选育高油品种的亲本材料。

 Taking 42 cultivars and 70 seedling individuals in Jiangsu Province Key Forest Improved Breed Base of Carya illinoinensis (Wangenh.) K. Koch as test samples, determination and diversity analysis on 10 nut traits and contents of fatty acids in kernels were conducted. The results show that the coefficients of variation of 10 nut traits are 2.86%-32.59%, in which, the coefficient of variation of kernel mass per nut is the highest, followed by single nut mass (28.83%). Fifteen fatty acids are detected in kernels of 112 test C. illinoinensis samples, in which, the octadecenoic acid content (252.485 mg·g^-1) is the highest, followed by the octadecadienoic acid content (133.952 mg·g^-1); the unsaturated fatty acid content is 396.105 mg·g^-1, accounting for 93.528% of the total fatty acid content, and the monounsaturated fatty acid content (254.919 mg·g^-1) is higher than the polyunsaturated fatty acid content (141.185 mg·g^-1). The coefficients of variation of contents of the 15 fatty acids are 3.145%-57.143%, in which, the coefficient of variation of tetradecanoic acid content is the highest, and the coefficients of variation of heptadecanoic acid, eicosanoic acid, hexadecenoic acid, and octadecatrienoic acid contents are also relatively high, which are all greater than 30%. The correlation analysis result shows that there are extremely significant positive correlations between single nut mass, nut horizontal diameter, nut vertical diameter, and nut lateral diameter; there are significant or extremely significant positive correlations between most of the contents of 15 fatty acids. The cluster analysis result shows that 112 test C. illinoinensis samples can be divided into 10 groups according to 10 nut traits, in which, group Ⅰ has the highest oil yield, group Ⅶ has the thinnest shell and the highest kernel yield, and group Ⅸ has the relatively large nut; 112 test C. illinoinensis samples can be divided into 4 groups according to the contents of 15 fatty acids in kernels, in which, group A has the highest contents of most fatty acids. The comprehensive analysis shows that there are relatively high diversities of nut traits and fatty acid contents in kernels of 112 test C. illinoinensis samples, in which, the contents of fatty acids in kernels of SD49 and ‘Pawnee’ are relatively high, and they can be used as parent materials for breeding highoil cultivars.