Fungi of the genus Pleurotus, in particular, species Pleurotus ostreatus (common oyster mushroom) are among most cultivated fungi in the world. Due to intense rates of development of studies in this field, efficient breeding programs are highly required in the search for new P. ostreatus strains. The principal traits used worldwide for selecting strains are intensity of fruitbearing, fruit body cap color (for some consumptive markets), and mycelium growth rate. In this connection, the objective of this work was to study these quantitative traits and to find molecular markers, which could be employed to accomplish breeding programs. In general, we found 12 genomic loci (quantitative trait loci, QTLs) controlling mycelium growth rate of oyster and six QTLs responsible for the fruit body cap color. The genetic map of P. ostreatus was constructed, and all markers of quantitative traits found by us were located on this genetic map. The obtained linkage map can be a useful tool for the accomplishment of breeding programs to improve economically important traits of oyster mushroom.

Two closely related commercially cultivated oyster mushroom species, Pleurotus pulmonarius and P. sajor-cajuhave been differentiated by traditional mating experiments as well as analysis of the...

The complete chloroplast genomes of red currant cultivar ‘Belaya Potapenko’ and gooseberry cultivar ‘Nekrasovskij’ were sequenced and assembled for the first time. The plastomes are 157,802 bp and 157,559 bp in length for Ribes rubrum and R. uva-crispa, respectively. The R. rubrum cp genome is 243 b.p. longer. It has one more protein-coding gene ycf1, which is pseudogenized in the R. uva-crispa cp genome. In total, 56 and 54 simple sequence repeats (SSRs) were identified within the assembled plastid genomes. The SSR content of plastid genomes was assessed for the 18 Saxifragales species. Phylogeny inference based on plastome data of 18 Saxifragales revealed that all Ribes species are clustered together on the phylogenetic tree, though R. fasciculatum seems to be the most distant from the other analyzed Ribes species. The position of taxa inside the Ribes genus clade does not support the concept of its division into five subgenera. All Ribes species share approximately the same set of protein-coding genes in their plastome sequences. There was multiple independent pseudogenization of the ycf1 gene within the Ribes genus as well as other Saxifragales taxa. Negative selection was observed for most of the genes in both the Ribes group and Saxifragales. A positive selection ratio was observed only inside the Ribes group for the ycf4 and clpP genes. Together with positive selection signatures, pseudogenization events of ycfs genes perhaps reflect that these genes’ evolution was important for Ribes’ adaptation. Thus, our study provides genomic resources and valuable reference for marker development, and makes some clarifications of the phylogenomics of the Ribes genus.

The potato is one of the most important food crops in the world. Improving the efficiency of potato breeding is of great importance for solving the global food problem. Today, researchers distinguish between six potato cytoplasm types: A, M, P, T, W, D. In the current study, the complete chloroplast genomes of Solanum tuberosum accessions with five out of the six major cytoplasmic genome types were sequenced (T-, W-, D-, A-, and P-genomes). A comparative analysis of the plastomes in potato accessions with different cytoplasm types was carried out for the first time. The time of origin of the different cytoplasm types was estimated. The presence of two main groups of chloroplast genomes among cultivated potato was confirmed. Based on the phylogenetic analysis of the complete plastome sequences, five main evolutionary branches of chloroplast genomes can be distinguished within the Petota section. Samples with A- and P- cytoplasm formed isolated and distant groups within a large and polymorphic group of samples with M-type cytoplasm, suggesting that A and P genomes arose independently. The findings suggest that the diversity of the T-genome in S. tuberosum Group Tuberosum could be initially low due to a bottle neck already existing at the origin of the Chilean clade. Differences in the rbcL gene sequence may be one of the factors causing differences in economically important traits in species with A and T-type cytoplasm. The data obtained will contribute to the development of methods for molecular marking of cytoplasm types and increase knowledge about the evolution and diversity of potato.

As a result of the accident at the Chornobyl Nuclear Power Plant, significant territories were exposed to ionizing radiation. Some isotopes, such as ¹³⁷Cs, are capable of making a significant impact on living organisms in the long-term perspective. The generation of reactive oxygen species is one mechanism by which ionizing radiation affects living organisms, initiating mechanisms of antioxidant protection. In this article, the effect of increased ionizing radiation on the content of non–enzymatic antioxidants and the activity of antioxidant defense enzymes of Helianthus tuberosum L. was studied. This plant is widely distributed in Europe and characterized by high adaptability to abiotic factors. We found that the activity of antioxidant defense enzymes, such as catalase and peroxidase, weakly correlated with radiation exposure. The activity of ascorbate peroxidase, on the contrary, is strongly positively correlated with radiation exposure. The samples growing on the territory with constant low exposure to ionizing radiation were also characterized by an increased concentration of ascorbic acid and water-soluble phenolic compounds compared to the controls. This study may be useful for understanding the mechanisms underlying the adaptive reactions of plants under prolonged exposure to ionizing radiation.