Breeding of subtropical ( Diospyros kaki L., Feijoa sellowiana Berg) and citrus crops ( Citrus reticulata Blan. var. unchiu Tan.) in FRC SSC of RAS

. This paper presents the results of the breeding work carried out by the Subtropical Scientific


Introduction
Breeding of subtropical (kaki persimmon, feijoa) and citrus crops is a long-term and continuous process, its main tasks are determined by the increasing requirements of intensive horticulture, the main ones are: early ripeness, early maturity, stable fruiting, restrained tree growth, resistance to biotic and abiotic stressors, as well as high quality fruits. Fruits are of great value as rich in sugars, acids, vitamins, pectin and bioactive substances [4; 10]. It is possible to speed up the breeding process by involving the sources of biologically and economically significant traits of persimmon, feijoa and citrus crops from different growing zones [2; 3; 5]. Genetic collections of many crops, including citrus fruits, kaki persimmon and feijoa have been created on the basis of FRC SSC of RAS, where cultivated plant species and cultivars, as well as their wild relatives, which are carriers of valuable traits for breeding work, are kept alive [9]. Deciphering the impurities of the germ plasm in modern cultivars (citrus, kaki persimmon) is important for the effective use of the collection biodiversity in breeding schemes for the new cultivars' development [6; 7;8]. The zone of humid subtropics of the Black Sea coast of the Krasnodar Territory provides cultivation of many subtropical crops; it is the only one in Russia for cultivating citrus crops and tea [1]. With the development and popularization of indoor, greenhouse and office gardening, the demand for many evergreen fruit plants is growing. Breeding work in this direction is carried out for restrained growth, remontant qualities, early maturity, leaf variegation and for many other decorative features.
The aim of the work is to analyze the main collection samples and create on their basis new high-yielding, low-growing, early-ripening forms, with high taste qualities of fruits and cultivars for the humid subtropics of Russia. The task of the research is to study the qualitative and quantitative indicators of fruits, forms and hybrids of the tangerine group, kaki persimmon and feijoa. In the course of research, a comprehensive phenotypic assessment of cultivar samples was carried out according to the UPOV protocol.

Results and discussion
As a result of previous studies, 28 most important sources of economically valuable traits were identified from the collections for use in breeding programs for the development of new forms and cultivars.
An analysis of the results of using various methods in breeding has shown that interspecific, intergeneric hybridization, clonal selection and the use of nucellar  Table 1 shows the basic characteristics of the obtained cultivars and hybrids.
Among the evergreen fruit plants, a significant place is occupied by a subtropical fruit crop -feijoa (Feijoa sellowiana Berg), which is of great economic importance in the region. To date, in the humid subtropics of the Russian Federation, industrial plantings of feijoa are about 70 hectares. The collection includes 34 cultivars, mainly of hybrid origin, on its basis 36 forms have been bred with different ripening terms, high yields and good fruit quality (without stony inclusions). The result of the breeding work is the creation of 3 new cultivars 'Dachnaya', 'Dagomysskaya', 'Sentyabrskaya' (Table 1). Fruit quality: total acidity up to 1.30%; the sum of sugars is 6.5 or more; fetal weight -up to 40 g Ripening term -early (mid-late September -early October) Yield -120 c/ha 'Dachnaya' Fruit quality: total acidity up to 1.50%; the amount of sugars 6.0 and more; fruit weight -40 -50 g Maturation period -the middle (early-late оOctober) Citrus reticulatа Blanco Yield -220 c / ha

Findings
Created new cultivars and hybrid forms of Diospyros kaki L., Feijoa sellowiana Berg. Citrus reticulata Tan. bred by FRC SSC of RAS are more adapted to the peculiar natural and climatic conditions of the humid subtropics of Russia, which distinguishes them from many introduced cultivars and allows replenishing and updating the zoned assortment.