Biochemical characteristics of small-fruited citrus from distant crosses with Fortunella Sw.

Abstract

Small-fruited citrus such as Fortunella Sw are becoming popular among a large variety of citrus fruits. Resistance, repeat flowering capacity, abundant fruiting combined with dwarfness, as well as the nutritional value of the fruits promote the use of the plants in hybridization to create new genotypes. The paper presents the quality characteristics of fruits of small-fruited hybrid forms derived from interspecific hybridization with Fortunella Margarita as the mother plant. The objects of the study were five promising forms: 202; 78; 90-3; Kip-14, Kalamondin-1, bred from interspecific hybridization under the auspices of the FRC SSC RAS. A brief pomological description of the size of the fruits and the juice extraction is presented in the paper. Moreover, two promising forms were established: 78 and 202. Kip-14 was distinguished by the smallest fruits with a mass of about 6.8 g and a thin skin. The study of the chemical composition of small-fruited hybrids showed that they were rich in vitamins, sugars and acids. In terms of quantity, sucrose predominates; its greatest amount was identified in the forms of Kalamondin-1 (38.09 g/kg), 78 (36.94 g/kg) and 202 (35.30 g/kg). It was revealed that in terms of sugar content, all hybrids were inferior to the original mother plant. 78 and Kip-14 were characterized by high content of soluble solids – more than 17%. 8 organic acids were identified in the fruits of the hybrids. Among the main organic acids, citric acid was dominant, the hybrid 202 – 6.53 g/100 g was indicated with high values of it. Kalamondin-1 had the highest amount of malic, succinic, acetic, lactic and oxalic acids. In terms of ascorbic acid, the hybrid Kip-14 was the leader (37.23 mg/100 g), and the fruits of this form were rich in sorbic acid (0.005 g/100 g). The largest amount of lactic acid (0.10 g/100 g) was observed in 90-3 hybrid. Fruits of 202 and Kip-14 did not contain oxalic acid.