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Fungal diseases of wheat are widely studied due to economic importance at global scale. Nevertheless, incorrect names of diseases and respective pathogen species, as well as inaccurate indication of their practical significance, is found in in the scientific literature. This may lead to confusion and misinterpretation of the phytosanitary situation. This review collects and structures the information about the main wheat diseases and pathogenic fungi causing them, as well as species emerging as a potential threat to wheat crops. The modern taxonomic status of the fungal species associated with different organs of wheat is given, their geographical distribution and the impact on the crop yield are characterized. Micromycetes are divided into three groups according to their phytosanitary significance. The first group is represented by fungi possessing great importance as pathogens causing the 25 main wheat diseases. The second group includes three diseases not found in Russia but significant for wheat production in other countries, thus posing potential risk for Russian grain farming. The third group consists of fungi causing 29 minor and poorly studied diseases with unverified harmfulness and controversial significance, for which the available data needs to be reviewed and confirmed. This dataset can be used as a reference for a more accurate and correct description of the phytosanitary situation. The review will also be helpful for more targeted studies using molecular methods to determine the area of fungi that cause wheat diseases, to track changes in their distribution boundaries and to clarify the harmfulness of poorly studied species.

A simple HPLC technique for the quantitative determination of phytotoxins (stagonolide A and herbarumin I) in liquid culture of the fungus Stagonospora cirsii S-47 has been developed. Some examples of its application are given. The technique was tested in a study of effects of the concentration of refined sunflower oil and the cultivation duration on the production level of these toxins. At an oil concentration of 0.5% or higher in modified Czapek medium with vitamins, the accumulation of S. cirsii biomass and the concentration of stagonolide A increased, while the concentration of herbarumin I decreased. Maximal amounts of both phytotoxins were obtained on the tenth day of submerged S. cirsii cultivation in flasks. When S. cirsii was grown in the same medium supplied with 1% of oil in a laboratory bioreactor, the maximal concentration of stagonolide A (116 mg/L) in the liquid culture was achieved after 5 days of fermentation followed by its considerable reduction after 6 days, while after 7 days of the submerged growth the maximal content of herbarumin I (116 mg/L) increased sharply. The technique of the phytotoxins analysis was used to monitor them during their isolation, as well as for preparative HPLC.

The fact that the genetics and biology of Drosophila have been studied in great detail ([5, 6, 11, 21, 25, 40–42, 55], and periodic publication of Drosophila Information Service) and that many mutations affecting various developmental stages are known, makes Drosophila one of the most suitable models for analyzing the way in which genetic information is expressed in the course of development. Embryos and larvae develop rapidly and are readily available for embryological experiments [17, 33, 37, 47, 53, 73, 74, 88]. Imaginal disks undergoing differentiation into the organs and tissues of the adult provide a unique basis for studying problems of determination and differentiation [27, 28, 32, 36, 66].