Search

Molecular analysis was performed with 88 barley accessions, including varieties cultivated in Belarus and those obtained from the collection of the All-Russian Institute of Plant Industry (IPI). A marker directed to the single nucleotide substitution (SNP) C698 --> T of the Bmy1 beta-amylase gene showed that the Sd2H and Sd3 alleles were absent from the Belarussian varieties. Five accessions with the Bmyl1 alleles determining thermostable isoforms of beta-amylase I were identified among the accessions from the IPI collection.

The insertion/deletion polymorphism of the angiotensin-converting enzyme gene (ACE) and the T174M polymorphism of the angiotensinogen gene (AGT) have been studied in six ethnic/geographic regions of Belarus. Significant intrapopulation differences in ACE genotype frequencies have been found for the northern and eastern regions (the Dvina and Dnepr basins, respectively). Significant differences in the AGT genotype frequencies have been found between populations of the Dnepr basin and populations of all other Belarusian regions. The allele and genotype frequencies of the genes studied in the Belarusian population and populations of other regions of the world have been compared. The frequencies of the insertion (I) and deletion (D) alleles of the ACE gene in the Belarusian population are 50.7 and 49.3%, respectively, which is similar to these frequencies in European countries. The frequency of the M allele of the AGT gene in Belarus is 16.6%, which is higher than its frequency in populations of European, African, and Asian origins.

The inheritance of nuclear morphological and molecular markers was studied in hybrid reciprocal populations of barley alloplasmic lines. A number of loci displayed a distortion of the Mendelian inheritance and a decrease in recombination rate depending on the cross direction and cytoplasm of parental forms. The segregations shifted towards both the mutant recessive and normal dominant phenotypes. The effect of cytoplasm on transmission and recombination of nuclear loci was shown.

The mode of inheritance of chloroplast and mitochondrial DNA (mtDNA) in rye x triticale intergeneric hybrids has been studied with the use of specific PCR markers for loci 18S/5S and 3'rbcL in organelle DNA. In rye x triticale BC1, mtDNA copies of two types, paternal and maternal, have been found; in BC2 plants, only paternal mtDNA and chloroplast DNA (cpDNA) have been detected. Mechanisms determining the inheritance and/or differential amplification of organelles of a specific type are discussed.

Inheritance of barley nuclear genes responsible for various morphological marker traits was studied in hybrid populations F2 and Fa. Nine marker genes showed deviation from Mendelian monogenic inheritance depending on the cross direction and maternal cytoplasm. Segregation biases to both recessive mutant and dominant normal phenotypes were observed. Mechanisms of the segregation bias related to cytoplasm substitution in iso- and alloplasmic lines are discussed.