Clubroot disease (causative organism Plasmodiophora brassicae Wor.) is among the most economically important and harmful diseases of the cole crops, and the damage due to this disease may reach up to 50-75% of the yield and even 100% in epiphytotics years. Even resistant varieties become susceptible over the years, because of appearance of the new pathogen races and change of climatic conditions in the main growing areas of the crop. In this context the Laboratory of Plant Immunity and Protection, of Federal State Budgetary Scientific Institution “Federal Scientific Vegetable Center” implements continuous phytoimmunological evaluation of collection and selection specimens and also directional material rather than just annual monitoring of causative organism dissemination in order to find new resistance sources. For this purpose an artificial infection background is used: compost obtained from decomposed nodules on the cabbage roots affected by clubroot disease (infection load 105-106 spores/cm3). The resistance of white cabbage varieties was evaluated during the harvesting period using five-point score of the root system damage, which formed the basis for categorization into resistance groups. For the analysis of artificial background intensity and specimen ranking the individual plants of the white cabbage variety Slava 1305, which is a susceptibility standard, were randomly planted in the entire area of the infection background. The impact of atmospheric conditions in the study year on the results of phytopathological evaluation of cabbage selection specimens against the infection background is demonstrated. Under unfavorable conditions for pathogen development (2014) the most specimens (74%) were categorized as relatively resistant, while in favourable for pathogen year 2015 relatively resistant specimens comprised only 5% of the total number of studied specimens. Since the same specimen may show different level of resistance depending on the year conditions, the stability of character manifestation is the important criterion for identification of the resistance resources. Phytopathological evaluation aimed on selection of clubroot-resistant forms in the Moscow region should last for at least three years even with the use of infection background. Long-lasting evaluation showed that the strains No 234/15,140/14,216/17 exhibiting high resistance to clubroot against artificial infection background regardless of the year conditions are the most valuable for selection. The resistance of white cabbage selection varieties to clubroot disease was studied against the infection background.

One of stressful factors the reducing harvest and quality of bulbs of garlic winter (Allium sativum L.) defeat is diseases of various etiology. Studying of influence of factors of the external environment and stability of a genotype on prevalence of diseases on landings of garlic winter and degree of their injuriousness in the conditions of the Moscow region was the purpose of researches; assessment of collection and selection samples of garlic winter and identification among them steady against the most economically significant diseases. Object of researches were grades and collection samples of garlic of the Federal Scientific Vegetable Center, winter from collections, and other selection institutions. Field experiments and assessment were carried out on a natural infectious background for a number of years. It is as a result established that in the conditions of the Moscow region during vegetation of a plant of garlic winter mainly are surprised mushroom diseases (mycoses) among which the dominating position is taken by fusariosis (micromycetes of the sort Fusarium spp). Defeat of garlic fusariosis is shown annually and with different intensity, depending on weather conditions. The analysis of literature and results of our researches show that number and a ratio of types of Fusarium spp. in a pathogenic complex changes in last years. The types which are earlier not noted on the culture of garlic in the Moscow region (since 2009 – F. avenacium, F. proliferatum, F. subglutinans and F. semitectum are registered; since 2017 – F. gibbosum and F. nivale). In a complex with highly aggressive types of F. solani and F. oxysporum they enhance injuriousness of fuzariosis withering and rots. Mushrooms of the sort Alternaria and other micromycetes of the sorts Stemfillium, Pythium, Embilisia, Verticillum, Cladosporium in the conditions of the Moscow region meet mainly in a complex Fusarium. Gray rot (the activator – Botrytis allii L.) it is more often shown in storage time and transportations of bulbs of garlic. These micromycetes enhance injuriousness of fusariosis and increase losses of a harvest of garlic winter, especially, in the conditions of sharp fluctuations of average daily temperatures and humidity of the soil during the different periods of vegetation. Results of long-term assessment are given in article, grades and perspective collection samples of garlic winter the steadiest against defeat with diseases in the conditions of the changing climate of a zone of Non-Black Earth Region are allocated.

35 viruses have been reported to infect peppers (Capsicum spp.) and those lead to economic losses like low  and  variable yield. Viral diseases are an important factor  provoking  low  yield and reduced  fruit  quality. In low volume hydroponics the spread of virus infection had local character. The two types of symptoms were revealed. The plants with symptoms of green mottle, chlorosis, deformation of mid-rib  in top leaves, and leaf blade rolling by edges inwardly were observed in breeding accessions with light-green fruit color such as ‘Maria’, ‘L-Ochrovanie’,  ‘Belosnezhka’. The deformation,  mottle and symptoms of inner necrosis can be seen on fruits. The degree of disease development reached 100%. The results of  enzyme-linked immunosorbent  assay (ELISA) and ImmunoStrips assays enabled to identify the tobacco mosaic  virus  (TMV). There  were  blight-yellow   mottle, wrinkling on entire plants and deformation and mottling on fruits. The symptoms appeared on the top leaves by the end of vegetation period that was caused by late viral impact. The degree of developing the disease was 10.5-25% on leaves and fruits that was less than on plants with green mosaic. Immunological  tests carried out  in open field showed the combined virus infections, consisting of TMV+CMV  with  degree  of  disease  development  was 37.5%. The rod-shaped particles, 30 nm in size, belonging to tobacco mosaic virus were discovered with the use of electron microscopy in pepper plants showing the symptoms of green and yellow mosaic.