In the framework of the program of creating nomenclatural standards of domestic cultivars initiated by the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR), nomenclatural standards of apple cultivars bred at the Pavlovsk Experiment Station of VIR have been developed. The cultivars in question are ‘Kormay’, ‘Kordonovka’, ‘Kryukovskoye’, ‘Krasnoshchyokoye’, ‘Leningradskaya Zelyonka’, ‘Leningradskiy Sinap’, ‘Leningradskoye Zheltoye’, ‘Lyubimitsa Tarasenko’, ‘Novogodneye’, ‘Novoye Polosatoye’, ‘Pashkevicha Krasnoye’, and ‘Sigovskoye’.

Background. Bread wheat (Triticum aestivum L.) is one of the major food crops of humankind. Powdery mildew, caused by Blumeria graminis f. sp. tritici, is the most destructive foliar disease capable of causing great yield losses in epidemic years. Breeding for resistance to powdery mildew is the most economical and effective way to control this disease. By now, 68 loci were identified to contain more than 90 alleles of resistance to powdery mildew in wheat. However, there is a permanent necessity in finding new sources of resistance.

The objective of the present study was to characterize the seedling powdery mildew resistance in some spring bread wheat varieties from the VIR collection and determine the inheritance of powdery mildew resistance in these accessions.

Materials and methods. The powdery mildew resistant varieties ‘SW Kungsjet’ (k-66036), ‘SW Kronjet’ (k-66097), ‘Boett’ (k-66353), ‘Batalj’ (k-67116), ‘Stilett’ (k-67119) ‘Pasteur’ (k-66093) were crossed with a resistant line ‘Wembley 14.31’ (k-62557) containing the Pm12 gene, and with ‘SW Milljet’ (k-64434); the variety ‘Sibirka Yartsevskaya’ (k-38587) was used as a susceptible parent and control. The hybrid populations F₂ were inoculated with the fungus population from local field and evaluated. The powdery mildew population manifested virulence to Pm1a, Pm2, Pm3a-f, Pm4a-b, Pm5a, Pm6, Pm7, Pm8, Pm9, Pm10, Pm11, Pm16, Pm19, Pm28, and avirulence to Pm12. The degree of resistance was assessed on days 8 and 10 after the inoculation using the Mains and Dietz scale (Mains, Dietz, 1930). The castrated flowers in the spikes were pollinated using the twell-method (Merezhko et al., 1973). Chi-squared for goodness of fit test was used to determine deviation of the observed data from the theoretically expected segregation.

Results. According phytopathological and genetic tests, juvenile resistance in the varieties ‘SW Kungsjet’, ‘SW Kronjet’, ‘Boett’, ‘Batalj’, ‘Stilett’ and ‘Pasteur’ is controlled by dominant genes, which differ from Pm1a, Pm2, Pm3a-f, Pm4a-b, Pm5a, Pm6, Pm7, Pm8, Pm9, Pm10, Pm11, Pm12, Pm16, Pm19, and Pm28. The varieties ‘SW Milljet’, ‘SW Kronjet’ and ‘Pasteur’ had identical resistance genes. Genetic control of juvenile resistance to powdery mildew in ‘Batalj’, ‘Boett’, ‘Stilett’, ‘SW Milljet’, ‘SW Kungsjet’, ‘Pasteur’ was governed by different genes.

Conclusions. The varieties ‘SW Kungsjet’, ‘SW Kronjet’, ‘Boett’ have been maintaining adult and seedling resistance since 2005, and ‘Batalj’, ‘Stilett’ and ‘Pasteur’ since 2017. Seedling resistance of these varieties to local powdery mildew population is controlled by dominant genes. A high degree of resistance was displayed by ‘SW Kungsjet’ and ‘SW Kronjet’ in the Novosibirsk Province, while ‘SW Kungsjet’ was resistant to mildew populations of Tatarstan. The variety ‘Pasteur’ manifested seedling resistance to leaf rust, and ‘SW Kungsjet’ was resistant to loose smut. By summing all the results, it may be suggested that the varieties ‘SW Kungsjet’, ‘SW Kronjet’, ‘Boett’, ‘Batalj’, ‘Stilett’ and ‘Pasteur can serve as good donors of powdery mildew resistance in wheat breeding.

A collection of 15 potato varieties ‘Seyanets Stepana’, ‘Stepan’, ‘Yekzotika’, ‘Fioletik’, ‘Kubinka’, ‘Vasilok’, ‘Lekar’’, ‘Severnoye Siyaniye’, ‘Ametist’, ‘Gurman’, ‘Perlamutrovyy’, ‘Ves siniy’, ‘Ves krasnyy’, ‘Klyukvenno-krasnyy’, ‘Malina’ was studied in the Arctic North. All the studied accessions demonstrated antioxidant properties and suitability for dietetic and therapeutic nutrition. The study was conducted in accordance with the VIR Guidelines. During a three-year study, the studied varieties displayed purple (blue) and red tuber pulp coloration of varying degrees of intensity. Even the varieties with white flesh ‘Kubinka’ (к-25276), ‘Vasilok’ (к-25199) had a slightly colored pulp along the vascular ring. The trait of colored tuber pulp variability is determined at the gene level. Probably, the long Polar day and low air temperatures contributed to the intense biosynthesis of anthocyanins. When studying economically valuable traits in the conditions of the Murmansk region, almost all varieties behaved as late ripening and unsuitable for cultivation for early production. The standard variety ‘Khibinskiy ranniy’ produced an average of 520 g/bush with 76% marketability in the trial dig. By the final harvesting, the standard yields an average of 800 g/bush with 87% marketability. The highest values of early yield accumulation (79-80% of the standard) in the Arctic North were displayed by the varieties ‘Fioletik’ (k-24754) and ‘Severnoye Siyaniye’ (k-25344). High yields at the final harvest were characteristic of the varieties ‘Fioletik’ (k-24754), ‘Gurman’ (vr.k.-p 523), and ‘Perlamutrovyy’ (vr.k.-p 526). In terms of the starch content, the varieties ‘Kubinka’ (19,3%), ‘Yekzotika’ (15,2%), ‘Gurman’ (16,7%) ‘Fioletik’ (14,2%), ‘Lekar’’ (13,2%), ‘Perlamutrovyy’ (14,2%) were distinguished. The high starch content is likely due to meteorological conditions and the genetic characteristics of the varieties. All varieties show signs of late ripening. For cultivation in the Arctic North, the varieties ‘Fioletik’ (к-24754), ‘Severnoye Siyaniye’ (k-25344); ‘Gurman’ (vr.k.-p 523), ‘Perlamutrovyy’ (vr.k.-p 526), and ‘Klyukvenno-krasnyy’ (vr.k.-p 522) can be recommended.

An urgent need to use a unified nomenclature for cultivated plants was indicated at the beginning of the 20th century by R.E. Regel, A.I. Malzev, K.A. Flyaksberger. Half a century later, an appendix to the International Code of Botanical Nomenclature (Stockholm, 1952) published the first formulated rules for naming cultivated plants, which provided a basis for the International Code of Nomenclature for Cultivated Plants issued as a separate edition in 1953. The primary goal of the Code was to eliminate confusion, promote order and uniformity in the naming of new varieties and the use of accepted variety names, i.e. to establish unified nomenclature rules. The main categories of the nomenclature for cultivated plants (cultivar, group, grex) do not represent a hierarchical system. So far, nine editions of the International Code of Nomenclature for Cultivated Plants had been published, of which four were translated into Russian (1953, 1958, 1961 and 1969). The prepared translation of the ninth edition is going to be published in the Vavilovia journal.

Transl. of: «International Code of Nomenclature for Cultivated Plants.
Ed. 9. Scripta Horticulturae. 2016;18:I-XVII+1-190».

Translators from English: I.G. Chukhina, S.R. Miftakhova, V.I. Dorofeev.