Huayi 7: A New Cultivar of Collectible Walnut (Wenwan Walnut) with Profound Chinese Cultural Background

Walnut (genus Juglans) is one of the oldest trees with harvestable products known to humans and has a history dating to 7000 BC in Persia (Vahdati et al. 2019).All parts of walnut trees have different uses, such as the trunk for timber production, roots and leaves for medicine, and walnut kernels for delicious foods.In addition, walnuts have a long history in popular culture, customs, and games in Silk Road countries (Vahdati 2014).The genus Juglans contains 20 species, some of which are rare tree species (Karimi et al. 2010).In China, collectible walnuts (Wenwan walnuts) have high artistic and economic value, mainly referring to Ma walnuts (Juglans hopeiensis Hu)."Wen" and "wan" in "Wenwan" respectively mean "traditional culture" and "playing, viewing, and admiring."Juglans hopeiensis, a rare species endemic to northern China, is mainly distributed in the hilly, midelevation area of Hebei, Beijing, Tianjin, and Shaanxi.At present, there are still some disputes about the phylogenetic position of J. hopeiensis in phylogenomics of the walnut family.According to the species' geographical distribution and leaf, flower, and fruit morphology, J. hopeiensis is considered as a welldefined lineage and a sister clade to Juglans mandshurica Maxim., Juglans cathayensis Dode and Juglans ailantifolia Carr.belong to Juglans, the section Cardiocaryon (Aradhya et al. 2007;Stanford et al. 2000); however, variety identification based on phenotype observations may have a certain degree of uncertainty (Nickravesh and Vahdati 2023).The evidence from randomly amplified polymorphic DNA (RAPD) markers, chloroplast simple sequence repeat (cp-SSR) analysis suggested that