Новые генетические источники для селекции видов Prunus L. на полиплоидном уровне

Abstract

This research is aimed at studying of the chromosomal number distribution within the new, in vitro cultured, amitotic
 clonal lines of Prunus species, at comparing of the fertility and size of pollen for triploid and hexaploid amitotic clones and
 at identifying of new genetic sources and their subsequent use in breeding. Methods. The standard cytological and statistical
 methods were used in this scientific work. Results. The regularities of induced polyploids output both from the initial number
 of chromosomes and from the origin and individual characteristics of the original genotypes were established. For amitotic
 hexaploid genotypes of hybrid cherry, high pollen quality was discovered at the level of 81,8–92,6 % of fertility (in triploids
 the 4,6–18,8 % of such pollen was found), therefore, the studied 4 clonal cherry genotypes (12-1-1Т2, 12-1-1Т6, 12-1-2Т3,
 12-1-2Тv) are recommended for breeding of resistant to fungal diseases varieties. No significant differences were found in the
 diameter of fertile pollen (46.3–47.8 μm) between cherry amitotic triploids and hexaploids. Therefore, in all likelihood, fertile
 pollen in triploids carries an unreduced triploid set of chromosomes. Prime scientific novelty. A completely new and original
 selection material for the genus Prunus L. – polyploid hybrids of P. fruricosa Pall. with rare East-Asiatic cherry species P. serrulata Lindl., P. canescens Bois., P. incisa. Thoub. were studied. The arguments in favor of a positive breeding prospect for the
 transfer of new cherries varieties to the hexaploid level (2n = 48), including an in vitro culture method of chromosome number
 doubling for the sterile triploid interspecific hybrids, have been obtained. The first created tetraploid (2n = 32) amitotic clonal
 lines of microcherry P. pumila L. must be tested in crosses with thorns and hybrids of thorns.