Single nucleotide substitutions (SNPs) account for the largest share of DNA polymorphism in virtually any organism, including humans, and have a significant impact on their life status. Detection of already known polymorphic nucleotides (SNP typing) is of great importance, which explains the extremely wide variety of existing methods for SNP analysis. One of the most widely used approaches is allele-specific PCR (AS-PCR) with primers characterized by differences in structure and the resulting ability to discriminate polymorphic nucleotides in DNA. AS-PCR is implemented in a variety of variants (about fifty), which are briefly considered in this review.

Botanic gardens and arboretums are being set up around the world to help create special collections of plants for the purpose of introduction, conservation of biodiversity and enrichment of the plant world, as well as scientific and educational activities, which, in addition, help in the fight against climate change. In our project, for the first time, it is proposed to create a specialized nectar-bearing arboretum, called the nectar-bearing landscape area of continuous flowering or a nectar forest, which, in addition to the above functions of ordinary arboretums, will also have economic value in the form of creating a universal food base for efficient beekeeping in our region. The first nectar forest with an area of about 18 hectares will be created in the south of the Nurimanovskiy district of the Republic of Bashkortostan near the village of Kyzyl-Barzhau. It is planned to plant a nectar forest, which will consist of 50% different species and forms of lindens, 20% willow and maple species, and the share of all other melliferous woody plants will be 30%. The total number of taxa of the genus Tilia L. (linden) will be 24; it is also planned to use at least 6 species of maple and 12 species and forms of willow. The total number of tree taxa involved will be at least 100. The total duration of flowering of honey plants in the nectar-bearing landscape area of continuous flowering with the participation of the entire population of planned taxa will be at least 193 days (from April 13 to October 24), which will cover the entire beekeeping season in the selected region. The organization of a nectar forest with high species diversity will increase the amount of honey obtained per unit area by at least 114% more compared to Tilia cordata plantations. Increasing the diversity of the forage base and its availability throughout the season will improve the health and stress resistance of bee colonies and increase the brood. In addition to honey production, the nectar forest will also perform the traditional functions of arboretums: scientific, educational, environmental, aesthetic, and recreational. Since the laying of a new arboretum involves the cultivation of a young forest that absorbs carbon dioxide most efficiently, the nectar forest can be used as one of the sites of the Eurasian carbon polygons, which is planned to be created in the Republic of Bashkortostan.

Due to the fact that single nucleotide substitutions account for the largest share of DNA polymorphism in almost any organisms and have a noticeable effect on their vital status, the detection of already known such polymorphic nucleotides is extremely important. This explains the huge variety of methods of such genotyping. Among the old approaches to the detection of polymorphic nucleotides, allele-specific hybridization with oligonucleotides stands out, which later received a new life in the form of fluorescently labeled probes. Also, such a method as PCR-RFLP, based on the cleavage of amplicons by suitable restriction endonucleases, whose sites contain polymorphic nucleotides or primers are designed in such a way that such sites arise during PCR, is not completely forgotten. The methods used relatively less frequently for detecting mutations in heteroduplexes using some chemical reagents, as well as using some endonucleases, are also briefly considered in this review.

As confirmation of the huge diversity of DNA content in the nuclei of plant cells, the boundary values of minimum and maximum parameters such as the number of chromosomes, varying in plants per haploid genome from two chromosomes to 480 (or even up to 720) chromosomes, as well as the "weight" sizes of genomes in picograms in the form of 1C-value with a range from 0.065 to 152.23 pg per haploid set of chromosomes. The importance of knowledge of the amount of DNA and the number of chromosomes for the implementation of projects for sequencing complete yet unknown plant genomes was noted. Examples of sequenced complete genomes of plants with very different sizes (less than 100 million bp and more than 30 billion bp) are also given. Attention is paid to the need to give the century-old term "genome" a new meaning, according to which it should already mean the entire amount of DNA in all chromosomes, regardless of ploidy, but not a haploid set, as before, since only the totality of all DNA (all alleles, both homologous and homeologous chromosomes) determines the vital status of a plant, and of any other eukaryotic organism. Attention is drawn to the fact that the concept of a "complete genome" includes various levels of their completeness from contigs and other draft quasi-haploid genomes to the so-called T2T genomes, which represent established nucleotide sequences chromosomally from "telomere to telomere". The most complete information about the organism can be given by the diploid genome, which is determined by the so-called phased assembly by haplotypes. At the same time, for plants and especially for cultivars of agricultural plants, as the reference genome should serve a pangenome that carries maximum information about the differences in nucleotide sequences characteristic of the sample under study. The use of plant pangenomic data in breeding will mark the transition to a new level of such work. Perhaps in the future, when the mass sequencing of truly complete diploid genomes in the T2T format begins, a new term will be needed for them, which could become "digenome" or briefly “dinome”.

АннотацияВ настоящей работе изучен химический мутагенез Triticum sinskajae, индуцированный азидом натрия. Семена исследуемого вида пшеницы предварительно обрабатывали растворами азида натрия различной концентрации. Воздействие мутагена оценивали по морфометрическим характеристикам полученных растений в период вегетации и плодоношения. Генетический полиморфизм мутантных форм определяли с помощью ISSR-анализа. С учетом показателей всхожести семян и дальнейшего роста растений установлена эффективная концентрация азида натрия для обработки T. sinskajae -0.1 мМ. Показано, что под влиянием азида натрия у растений возникали различные морфологические отклонения от нормы: в низких концентрациях он способствовал увеличению высоты стебля и колоса, а в высоких -приводил к их уменьшению. Существенных различий по длине листьев и по массе 1000 зерен между мутантами и диким типом не выявлено. Сделан вывод о том, что ISSR-анализ может быть использован в качестве диагностического подхода для оценки общего мутагенного воздействия химических реагентов на геном. По результатам проведенной работы отобраны 78 мутантных форм T. sinskajae, сохраняющих короткостебельность в ряду поколений.Ключевые слова: Triticum sinskajae, мутация, азид натрия, ISSR-анализ, генетический полиморфизм, диплоидные пшеницы, селекция Введение Triticum sinskajae A. Filat. et Kurk (пшеница Синской) является дикорастущей диплоидной пшеницей, близкородственной таким видам, как Triticum monococcum L., Triticum boeoticum Boiss. и Triticum urartu Thum. ex Gandil., из которых лишь первый культивируется, считаясь одним из наиболее древних одомашненных человеком растений [1]. Пшеница Синской, получившая свое название в честь известного российского тритиколога Е.Н. Синской, была обнаружена в начале 70-х годов XX в. при очередной репродукции на Среднеазиатской и Дагестанской станциях Всероссийского института генетических ресурсов растений имени Н.И. Вавилова (далее ВИР) образцов T. monococcum, привезенных П.М. Жуковским еще в 1926 г. из Турции. Однако по своим признакам она значительно отличается от T. monococcum и образует отдельный таксон видового ранга [2]. Взрослые растения данного вида достигают 120 см в высоту, отличаются большой кустистостью, а также имеют тонкую и полую соломину. Стеблевые узлы короткие, зеленые, с бурой каймой снизу, опушены густыми короткими Чемерис Алексей Викторович, доктор биологических наук, главный научный сотрудник Институт биохимии и генетики УФИЦ РАН пр-т Октября, д. 71, лит. 1Е, г. Уфа,