Evaluation of the descriptive characteristics of chestnut

Abstract

The chestnut (Castanea spp.) tree is extremely valuable for it ecological role in the environment as well as its role in the production of sweet, edible nuts, decay resistant timber, and the production of chemical compounds such as tannins. Although native to the temperate zone of the northern hemisphere, it has been planted successfully throughout the southern hemisphere including Australia, New Zealand and Chile. Currently, the genus Castanea is represented by 13 species ranging in size from shrubs to large trees. Five species of Castanea are native to East Asia, seven species are native to North America and one species is native to Europe. Many chestnut cultivars have been selected or bred for various purposes such as improving nut or timber quality, increasing yield, enhancing resistance to diseases or pests and winter hardiness. For the purpose of registering new cultivars, distinctness, uniformity and stability (DUS) of the cultivars need to be described and verified. For this aim, morphological characteristics of the cultivar candidates should be determined. There are many morphological traits used for identifying cultivar candidates. However, reliable characteristics need to be selected and scored. Generally, the International Union for the Protection of New Varieties of Plants (UPOV) criteria have been used for this purpose, but we believe the UPOV criteria need to be updated. In this review, various descriptive morphological chestnut parameters are discussed to promote the list of current and new criteria.