Abstract: 【Objective】 Walnut is an important economic tree species in China, and its germplasm resources are very rich. There were many problems in the processing of germplasm preservation such as large area occupied, higher management costs, which brought great difficulties to the conservation, utilization and evaluation. Therefore, construction of walnut core collection is very important for preservation, study and application of Juglans regia L. germplasm resources.【Method】 Based on AFLP markers, candidate core collections were constructed by using proportional strategy and UPGMA clustering sampling method within subgroups after dividing 131 Juglans regia germplasm into 45 subgroups. The core collection was eventually identified by comparison of the genetic diversity parameters of these candidate core collections, such as the number of polymorphic loci, percentage of polymorphic loci, and morphological indicators. 【Result】The core collections including Tianqiao1 from Hebei province, Xiluo2 and Xilin1 from Shaanxi province, Jinglong1 from Shanxi province, Fenghui from Shandong province, Liaoning8 and Liao73013 from Liaoning province, Wen185 from Xinjiang, Lvbo from Henan province, Beijing746 from Beijing, Vina from America, Qingxiang from Japan, Anbian1 from North Korea, reserved 10% samples of original collection. The retention rate of polymorphic loci was 75.4% in the core collection.【Conclusion】The core collection which was constructed in this study can largely represent the genetic information of the original germplasm, and it was matched with the requirements of the core collection.

Key words: Juglans regia L. , core collection , amplified fragment length polymorphism (AFLP) , genetic diversity