Economical and biological characteristic of triploid scab immune apple cultivars (gene-Vf)

Brief results of the long-term (over 60 years) work for apple assortment improvement in the Central region of Russia are given. It is shown that at the first stage of the work common methods of breeding were used with Michurin, North-American and Canadian cultivars as initial forms from the large gene pool of Orel Zonal Fruit-Berry Experimental Station (at present: All-Russian Research Institute of Fruit Crop Breeding). Apple cultivars Veteran, Kulikovskoye, Orlovskoye Polosatoye, Orlik, Pamyat Voinu, Radost Nadezhdy, etc., were developed and introduced into wide production. The Institute became a pioneer in the development of the first Russian scab immune apple cultivars (Vf) - Afrodita, Veniaminovskoye, Imrus, Candil Orlovskiy, Orlovskoye Polesie, Svezhest, Solnyshko, Start, Stroevskoye, etc. The evaluation of heteroplid crossings of different types: 4x x 4x, 4x x 3x, 4x x 2x, 3x x 4x, 3x x 3x, 3x x 2x, 2x x 4x and 2x x 3x preceded breeding of triploid cultivars and that made it possible to determine their breeding value. Microsporogenesis, macrosporogenesis and the formation of male and female gametophyte were studied in initial tetraploid forms of apple. That favoured the rational work planning. First in the world a series of triploid apple cultivars was developed from the intervalent crossings 2x x 4x. These cultivars are characterized by a less expressed periodicity of fruiting, higher marketability of fruit and their weight and higher autogamy. These and other triploid cultivars are widely introduced in the orchards of the Central region of Russia. Six triploid cultivars have been included in the State Register of breeding achievements admitted for use. Triploid apple cultivars having immunity to scab are of special value: Alexandr Boiko, Vavilovskoye, Zhilinskoye, Maslovskoye, Prazdnichnoye, Spasskoye and Yablchny Spas. Two triplod cultivars with immunity to scab have been developed from the hybridization of diploid cultivars (2x x 2x). Economical and biological characteristics of these cultivars are given in this paper. Broad introduction of these apple cultivars into industrial and amateur orchards will favour import substitution of fruit.