Notice of a new Crataegus ‘Kokhno’ and +Crataegomespilus

Abstract

Crataegus (+Crataegomespilus) ‘Kokhno’ is a new graft chimera originated from the junction where Crataegus germanica (= Mespilus germanica) scion was top-grafted onto a stock Crataegus sp. In 1993, in the arboretum of one of the forestry-division offices in the Volhynia region, Vladyslav Oleshko found a putative hybrid between hawthorn and medlar, which was named in honor of well-known Ukrainian dendrologist Mykola Kokhno. He believed this plant was the result of a crossing between Mespilus germanica and Crataegus ucrainica because it was characterized by heterophylly having a mixture of both medlar and hawthorn leaves. The flowers of this plant are not solitary but placed in corymbs. The fruits are not aligned in size and range from 0.5–5.0 cm in diameter. The study of this hawthorn-medlar in the dendrological collection of the M.M. Hryshko National Botanical Garden (Kyiv, Ukraine) led to the conclusion that it is a graft chimera, not a hawthorn-medlar sexual hybrid. This hawthorn-medlar cultivar is morphologically similar to medlar but differs in the arrangement of flowers and fruits. The fruits typical for varietal medlar develop from solitary flowers, whereas atypical small fruits are located in groups. Both types of fruits have no germs in the stones. The cultivar ‘Kokhno’ is adapted to the Forest-Steppe of Ukraine and performs well as an ornamental and fruit plant. An outline of the history and nomenclature of graft hybrids (chimeras) between Crataegus and Mespilus is given.