Pre-harvesting germination of grain causes a considerable loss and it is one of the reasons for the decline of sowing and technological properties of grain. In this regard, the aim of this work was to elucidate the role of hydrolytic enzymes in the grain crop sustainability to germination in the ear. The object of the study were di- and tetraploid forms of rye and hexaploid forms of triticale and secalotriticum. The research allowed to select a stable and productive form of cereals to evaluate the resistance to grain germination for assessment of resistance to germination of grain at the root. It is shown that the germination of the grain at the root is affected by the ploidy of rye and the type of cytoplasm from heteroplasmic triticale. It is shown different levels of activity of proteolytic and amylolytic enzymes in the studied genotypes of cereals. Winter triticale had a marked higher level of activity of neutral, alkaline protease and α-amylase. Variation in the level of BAPase activity is 7.15– 24.4 EA/g. a. d. m. and α-amylase activity – 92 –118.7 mg/ml∙h. It is shown the close correlation between the activity of alkaline BAPase, α-amylase and resistance to the cereal grain germination in the ear. Heterogeneity of an electrophoretical range of proteins at the studied genotypes of rye and triticale is shown. The obtained data make a contribution to clarification of the reasons underlying the resistance of cereal cultures to germination of grain at the root and open possibilities of identification of their markers for use in selection.

Results of cytogenetic study of genome stabilization in hexaploid secalotriticum ( S/RRAABB, 2n = 6x = 42) in F1–9 are presented. Nuclear-cytoplasmic specificity and cytogenetic factors of genome stabilization in secalotriticum (subspecies cytotype specificity, genotypic specificity of hybrids, origin, polar orientation of centromeres, type of division and chromosome segregation in meiosis) were established. Suitability of the development of independent directions of heteroplasmic triticale selection was substantiated.

The results of cytogenetic studies of genome stabilization in secalotriticum are presented. Comparative analysis of microsporogenesis in hexaploid secalotriticum, triticale, and reciprocal hybrids of them (S/RRAABB, T/AABBRR, 2n = 6x = 42) was carried out. The cytogenetic properties and genotypic factors of genome stabilization in heteroplasmic triticale were found. The inheritance by the secalotriticum of the genotypically caused first meiotic division, the so-called reduction division, ofunivalents from original combinations of rye-triticale hybrids was demonstrated for the first time.

Представлены результаты цитогенетических исследований стабилизации генома секалотритикум. Проведен сравнительный анализ микроспорогенеза у гексаплоидных секалотритикум, тритикале и их реципрокных гибридов (SRRAABB, TAABBRR, 2n = 6x = 42). Установлены цитогенетические особенности и генотипические факторы стабилизации геномов гетероплазматических тритикале. Впервые показано наследование секалотритикум генотипически обусловленного редукционного первого мейотического деления унивалентов от исходных комбинаций ржано-тритикальных гибридов.

The karyotype formation was studied in the F1BC1 and F1BC2 hybrids of Secale cereale L. ssp. tetraplodium Kobyl. (RRRR, 4x = 28) and Triticale (AABBRR, 6x = 42). The hybrid karyotypes were heterogenomic for homeologous chromosome groups of the wheat and rye genomes. The hybrids differed in cytological stability, the balance of chromosomes of the original species, and the fertility of spikes. The majority of F1BC1 and F1BC2 plants were cytologically unstable and unbalanced in chromosome composition and displayed a low spike fertility. Cytologically stable hexaploids occurred in F1BC1 and F1BC2 at a frequency of 1.0 and 9.5%, respectively. The resulting hexaploid secalotriticum lines (RRAABB, 6x = 42) were genotypically diverse and morphogenetically various. The genetic factors responsible for the diversity of the F1BC1 and F1BC2 rye-triticale amphiploids and early secalotriticum generations are discussed.

Diversity of photosynthetic characteristics determined by plant genotypes provides the grounds for the increase in potential crop productivity by means of producing plant forms whose photosynthetic apparatus (PSA) has optimal size and functional efficiency. Parental forms of winter rye ( Secale cereale L.) and their interline and intravarietal reciprocal F 2 hybrids were compared in terms of photosynthetic pigment (PSP) content, characteristics of chlorophyll a (Chl) fluorescence, some morphological traits, and grain productivity. At the booting and anthesis stages, significant divergence in chlorophyllous pigment content and Chl a fluorescence parameters was observed for winter rye inbred lines, rye varieties, and hybrids. The hybrids were revealed whose elevated grain productivity correlated with high PSP content and the highest photosystem II (PSII) activity. Analysis of correlations in reciprocal F 2 hybrids at booting and anthesis stages of rye development showed that accumulation of PSII is related to stem-forming capacity and to the flag leaf surface area. In reciprocal hybrids, the correlations between morphological traits, grain productivity, plastid pigments, and photochemical activity were subject to variations. The relationships between PSA parameters and grain productivity in winter rye F 2 hybrids varied depending on the developmental stage as well as on crossing combination; this relation was largely determined by the choice of pairs for hybridization, by direction of crosses, and by genetic features of parental forms.

Polymorphism of heterochromatin C-blocks in chromosomes of rye genome has been studied in the F1BC1 hybrids and the D/A substitution lines of rye-wheat amphidiploids (Verasen x L374, Novosibirskaya x x L246)--secalotriticum for revealing cytogenetic markers of rye chromosomes. An increase in polymorphism for the presence and value of heterochromatin blocks in chromosomes of rye genome was shown in the F1BC1 hybrids ((Verasen x L374) x L145 x L145) and unstable genotypes of the F6BC1 chromosome substitution lines (line 118 (Novosibirskaya x L246) x Reso x Reso), line 104 ((Verasen x x L374) x Garmoniya x Garmoniya) that was related to activation of mobile genetic elements present in cereals. Heterochromatin markers of all seven chromosomes in rye genome were revealed. The polymorphism system of heterochromatin blocks may serve as a marker for specificity of the linear chromosome structure during reconstruction of synthetic cereal genomes, and as a test for cytological and morphogenetic stability of hybrid polygenomes in a series of generations.

Results of cytogenetic analysis of microsporogenesis in rye-triticale F1 hybrids (RRABR, 5x = 35) are presented. Meiosis of pentaploids is described as the key stage in the synthesis of secalotriticum, lines with intergenomic substitutions of chromosomes, or alloplasmic rye and wheat lines. Properties of meiotic processes and cytological mechanisms in formation of functional gametes and plants of various genomic and chromosomal composition are discussed.

The accumulation of photosynthetic pigments in underflag and flag leaves as well as the process of microsporogenesis in lines of tetraploid Secale, hexaploid Triticale, and hexaploid Secalotriticum were studied. Significant positive correlations were found between the amounts of chlorophyll a (Chl a), carotenoids (Car), Chl a/b ratio, and the normal proceeding of meiosis. High probability of paternal type of inheritance of specifities of meiosis of pollen mother cells and variation in photosynthetic pigments during plant transition from the stalk-shooting to heading stage were demonstrated.