GENETIC AND BIOCHEMICAL ASPECTS OF THE ASSOCIATION OF THE PPD-D1 LOCUS WITH THE RESISTANCE OF WINTER SOFT WHEAT TO LOW TEMPERATURE

Abstract

The aim of this work was to study the expression of some enzymes under the influence of unfavorable temperature conditions on plants that differ in allelic composition of Ppd genes. To accomplish this goal, the following tasks were set: 1) to carry out qualitative and quantitative analysis of electrophoregrams of multiple forms of antioxidant enzymes (catalase, peroxidase, superoxide dismutase); 2) to establish whether there is a relationship between the spectra of the enzyme under study and the tolerance to low temperatures and allelic composition of the Ppd-D1 gene.Material. Winter wheat varieties: Mironovskaya 808 (recessive alleles of the Ppd-D1 gene) and Tira (the dominant allele of the Ppd-D1 gene). Methods. Electrophoresis. Complex comparative analysis. Methods of descriptive statistics. Computer data processing.Results. It was shown that in varieties that differ in the composition of Ppd-D1 alleles and resistance to hypothermia gene-enzyme systems function in a different, often opposite way. Moreover, the difference was observed both in control conditions and under stress. This indicates that for the formation of adaptation, not only the peculiarities of the reaction of the metabolic reaction to adverse conditions, but also their initial state are important.In Mironovskaya 808 plants, unlike Tire, peroxidase plays a major role in neutralizing peroxide. This is manifested both in higher activity and in features of changes in enzyme expression during hypothermia, as well as in the ratio of peroxidase activity to the activity of other antioxidant enzymes. The leading role of peroxidase, due to its versatility, leads to a finer regulation of cellular metabolism during adaptation. In addition, in Mironovskaya 808, in response to the action of low temperature, the functioning of specific peroxidases, ascorbate peroxidase and ferulic-specific peroxidase, changes in the opposite way, compared to the variety Tira. The expression of such an important antioxidant enzyme as SOD also changes in different ways.Based on the data obtained, it can be assumed that Tira's system of protection against oxidative explosion in stress does not cope with the excess of superoxide radicals formed.