Strategy of chaenomeles selection based on the chemical composition of fruits

To define a selection strategy based on biochemical characteristics, suitable combination of parental pairs for breeding, as well as valuable genotypes determination we studied genetically distant forms of Chaenomeles japonica, C. speciosa, C. cathayensis, C. × superba from the collection of Nikita Botanical Gardens on their fruits chemical composition using standard methods. Studied genotypes of all Chaenomeles species are characterized by a high content of organic acids, including ascorbic acid, proanthocyanidins, pectin, low sugar-acid index and sugar content varied within wide limits. The greatest accumulation of soluble solids was typical for C. speciosa (18.16%). With the exception of C. cathayensis (3.44%), the average amounts of organic acids are similar in other three species (3.75-4%). The highest accumulation of ascorbic acid is characteristic for C. speciosa and C. cathayensis genotypes (244.58 and 258.25 mg 100 g^-1). The greatest amount of total sugars was observed in the fruits of C. speciosa (5.2%). C. speciosa also differed from other species by the highest sugar-acid index. The highest content of proanthocyanidins, causing astringent taste, was revealed in C. cathayensis (1976 mg 100 g^-1) and the lowest in C. × superba (554.18 mg 100 g^-1). C. speciosa is characterized by the highest content of total pectin in fruits (1.82%), water-soluble pectin (0.65%) and protopectin (1.21%). Thus, C. speciosa genotypes are the most perspective for selection due to the high amount of most chemical components.