Research staff All-Russian Scientific Research Institute of Vegetable Growing – Branch of the Federal State Budgetary Scientific Institution Federal Scientific Vegetable Center in collaboration with Russian state agrarian University – Moscow Timiryazev agricultural Academy conducted research (2014-2016) on the effect of fertilizers and plant growth regulators on changes in the quality of onions of the Pervenets F1, Bennito F1 hybrids and Poisk 012 F1 during storage. As a result of research, the greatest effect was obtained from the complex application of N90P90K90 in combination with trace elements (tenso-cocktail) and a growth regulator Zircon. This system allowed to obtain high biochemical parameters of onions. At the end of the 7 months of storage (October-may), the highest dry matter and sugar content and the minimum nitrate content was observed in Pervenets F1 onions, as well as in hybrid Bennito F1. In the latematuring hybrid onions Poisk 012 F1 at the end of storage, the dry matter content decreased to 6,8-7,3%, sugars to 3,6-4,1%, vitamin "C" to 3,2-4,9 mg%, and nitrates increased to 92,1 mg/kg, which led to a decrease in product quality and large losses of onions from diseases and natural losses (up to 48-59%). The main reason for these losses was the lack of maturity of bulbs,low solids and sugars during harvest. It is obvious that for long-term storage it is necessary to use bulbs with a dry matter content of at least 10%. It was found out that feeding of onions during the beginning of the formation of food organizations with potassium nitrate, treatment with a growth regulator of Zircon and a complex of microelements of tenso-cocktail contributes to better preservation of the quality of onions.

Relevance. The quality of food products in Russia and delivered to retail chains for mass consumption is currently one of the most important food safety priorities.Methods. The article contains the results of studies of nitrate content in fruit and vegetable products during 2018-2019 period, obtained from VNIITeK laboratory, comparisons were made with the permissible level of Maximum residue levels (MRL) for nitrate, which are set in Technical regulation TR TS 021/2011. Totally, 252 samples were studied, for the period from January 2018 to April 2018 inclusive 2019.Results. The nitrate content was determined by liquid chromatography. It was shown, that content of nitrate ions in fruit and vegetable products varies in a wide range, depending on the selected group, at the same time, the lowest level of nitrate is established in children 's fruit puree, the highest levels are found in tomato sauce.

Primal problem of vegetable growing is constant supply of the population with all types of vegetables, including green cultures. Green cultures are vegetables that have high nutritional value and precocity. However they often are infected by phytopathogenic microorganisms already at initial stages of ontogenesis at cultivation in closed soil conditions. It leads to emergence of disjointed shoots, deterioration of growth and development of plants and loss of quality. Now in the Republic of Belarus a number of biological substances on the basis of bacteria Bacillus was developed. They are used against diseases of plants of mushroom and bacterial etiology. However there is not information about influence of bacteria on quality of products of green cultures. The aim of the work was studying of influence of two strains of bacteria Bacillus that were introduced in peat substrate on efficiency and quality of lettuce. Two strains of bacteria Bacillus were used in the work. They were selected from the soil. The strains are Bacillus subtilis M9/6 and Bacillus amyloliquefaciens 23TM that have high antagonistic activity to a wide range of phytopathogens. Cultivation of plants carried out in containers of 250 ml under light installations with illuminating intensity 13-15 thousand luxury and lasting irradiating of 14 hours before technical ripeness of lettuce. It was established that the application of strain Bacillus subtilis M9/6 (in concentration 106 cells/ml, 10 ml/l of substrate) and the strain Bacillus amyloliquefaciens 23TM (5 ml/l of substrate) in substrate before sowing increased nutrition value of lettuce. Dry matter content, water-soluble carbohydrates (mono - and disaccharides) content and vitamin C content increased. The bacterial strain B. amyloliquefaciens 23TM also promoted accumulation of vitamin B2. The content of nitrates in lettuce leaves decreased on 50,3% and 39,1%, respectively. It was shown that the application of bacteria in substrate before sowing of crop has a greater influence on quality of lettuce, than watering of shoots.

Relevance. The priority direction in vegetable growing is the scientifically justified use of types and doses of micronutrients that can increase the yield of watermelon fruits and improve their quality. Due to the large number of different types of fertilizers currently appearing on the market, it is necessary to choose the right ones and study them in optimal doses for growing high-quality melon products.Material and methodology. Objects of research: watermelon varieties Meteor, Zemlyanin, Kholodok and preparations: iron chelate, zinc chelate, vegetable Aquarin. Options using these fertilizers for double foliar treatment of plants during the growing season have been studied. The research was carried out during 2019-2021 at the Bykovskaya melon breeding experimental station.Results. During the study, a positive effect of the tested drugs on the quantitative and qualitative indicators of products was established. As a result of foliar treatments of plants in all variants, the yield exceeded the control variant (without treatments). A comparative analysis of biochemical data showed that the dry matter content was at a fairly high level. As a result of the use of zinc chelate in the Meteor and Kholodok cv., the dry matter content increased by 0.4%. A similar increase in the indicator was obtained when using the drug Aquarin vegetable on the Zemlyanin and Kholodok cv. The content of total sugar in the Meteor and Kholodok cv. was higher than the control (without treatments), and in the Zemlyanin cv. it was at the control level. The fructose content in the tested variants of all varieties exceeded the control. As a result of the use of water-soluble fertilizers for plant treatment, the content of ascorbic acid increased in the variants with treatment in the Meteor cv. – by 1-1.5 mg%, in the Zemlyanin cv. – by 0.8-1.1 mg%, in the Kholodok cv. – by 0 .1-0.7 mg% compared to control (without treatments). Nitrate levels in watermelon fruits of different ripening periods did not exceed the maximum permissible concentration (60 mg/kg).

Relevance. The nutritional value of gourds is quite high and is of great importance in the life of the human body. A significant point in modern melon growing is to increase yields without reducing the quality of the products obtained. Therefore, it is necessary to develop new methods of cultivation technologies that allow obtaining stable fruit yields without reducing the quality of table watermelon products of different ripeness groups, in the climatic conditions of the Volgograd region.Material and methodology. The object of research is a watermelon of medium ripening, variety Zemlyanin, and late ripening, variety Kholodok. We studied new types of water-soluble fertilizers Fe chelate, as well as Vegetable Aquarin, by using them for soaking seeds before sowing and processing plants during the growing season.Results. The use of chelated fertilizers in the technology of growing table watermelon of medium and late ripening is an effective technique for obtaining stable yields. The use of water-soluble fertilizers, with various methods of their use, provided an increase in the yield of Zemlyanin watermelon by 2.7-27.8%, and Kholodok watermelon by 2-22.4% in comparison with the control (without treatments). The largest fruits were obtained in the variant Aquarin vegetable (plant processing) Zemlyanin variety - 6.8 kg and Kholodok variety - 8.4 kg. A comparative analysis of the biochemical composition of fruits showed that water-soluble chelate fertilizers do not have a negative effect on the accumulation of nitrates in varieties of medium and late ripening. As a result of research, a positive effect of water-soluble micronutrient fertilizers has been revealed on improving the quality of fruits, which increased the content of ascorbic acid and sugars.

The review is devoted to the nutritional significance and prospects of garden rhubarb (Rheum rhabarbarum L.) utilization in food industry. High yield of juice reaching 90% and the ability to complex rhubarb stems processing for juice production and pectin extraction from rhubarb stem pomace are empathized. Rhubarb stems pomace recorded up to 21-23 % of pectin, which is significantly higher than in natural industrial sources of pectin. Medicinal value of rhubarb juice is discussed: antioxidant, anti-inflammatory, anti-carcinogenic, cardioprotective and anti-diabetic properties are indicated. Examples of high antioxidant content and unique organic acids composition of rhubarb juice are highlighted. Sorbic and benzoic acids are indicated as important components of juice widely used in food industry as food preservatives. Citric acid is shown to be the main component of rhubarb organic acids in spring. Special attention is paid to the non-waste production of juice thanks to the possibility of pomace processing for pectin recovery. Juice biochemical characteristics of four garden rhubarb cultivars (selection of Federal Scientific Center of Vegetable Production) are described: Udalets, Malakhit, Zaryanka and Krupnochereshkovy). Expediency of further selection on high anthocyanin content in rhubarb stems are empathized.

Relevance. Many authors note the existence of significant genotypic differences in the assimilation of nitrogen and the accumulation of nitrates by lettuce, point to the additive-dominant nature of the inheritance of the trait. The aim of the work was to evaluate the response of lettuce of various cultivars to mineral nutrition stress created against a nitrogen-deficient background (N0) and with an increased dose of nitrogen (N200).Material and Methods. In a microfield experiment on well-cultivated soddy-podzolic soil, a collection of lettuce varieties belonging to the main cultivated variety types was studied. The varieties differed in geographical origin, early maturity and morphological characteristics.Results. Differences in yield between varieties against the background of N200 were 4.5 times, and against the background of N0 – 5.7 times. Against an increased background of nitrogen nutrition, the highest yield – 2.22-2.64 kg/m2 was formed by the following varieties: All the Year, Quedlinburger Dickkopf, Berlin Yellow, Great lakes. Against a nitrogen-deficient background, Azart and Odessa Kucheryavets varieties stood out in terms of yield, which absorbed soil nitrogen better than others. The content of nitrates in lettuce plants of different varieties varied more strongly when grown on the background of N200 and ranged from 10.7 to 13.6 times (on average over 2 years – 11,2 times), on the control of N0 – 33 times. Varieties accumulating maximum NO3 under conditions of excess nitrogen nutrition were revealed. Lettuce Romaine (Lactuca romana) – 353 mg/kg and White paris cus (198 mg/kg) had a low content of NO3. The period of the maximum increase in biomass also corresponded to the maximum decrease in NO3 in plants. Power function equations were calculated to estimate the rate of change in biomass and NO3 content. The results indicate that there may be some scope for NO3 reduction in lettuce through cultivar selection or breeding.

In field experiments, the optimal pre-irrigation moisture levels of the soil, plant density and fertilizer regulations to ensure maximizing the table beet crops with good qualities of roots under foothill zone of the Chechen Republic have been found.

Increase in green vegetables popularity in nutrition and medicine promotes investigations of new cultivar and hybrid biochemical parameters. Nutritional value and antioxidant status of three Rumex representatives: Rumex acetosa L. (Krupnolistny cv.), Rumex sanguineus L. (prospect genotype) and Rumex confertus Willd. were studied. Antioxidant defense parameters (total antioxidant activity, polyphenol and ascorbic acid content) decreased in accordance to: Rumex sanguineus L. > Rumes confertus Willd. > Rumex acetosa L. Thus the ascorbic acid content in bloody dock (R. sanguineus)  reached 129 mg/100 g which was 1.48 times higher than in Russian dock (R. confertus) and 3.17 times higher than in garden sorrel (R. acetosa). The total chlorophyll content was also the highest in bloody dock (17.74 mg/g d.w.) compared to 15.88 mg/g in R. confertus and 13.07 mg/g in R. acetosa leaves. The new R. sanguineus genotype was characterized by high decorative properties and demonstrated twice higher oxalic acid content compared to R. acetosa, Krupnolistny cv., and 1.5 times higher value than in R. confertus. High decorative and medicinal value of R. sanguineus was connected to a great extent with the intensive anthocyanin accumulation reaching 7.2% and high nitrate content. The results of the present study indicate high prospects of R. sanguineus genotype utilization in landscape design, food industry and medicine.

Relevance. A rare representative of the Apiaceae family the garden chervil is widely used abroad in nutrition and in folk and traditional medicine.Methods. Evaluation of nutritional potential of Anthriscus cerefolium (L.) Hoffm and Anthriscus sylvestris Hoffm grown in Moscow region is achieved using the parameters of ascorbic acid, polyphenols, flavonoids, total antioxidant activity of ethanolic extracts.Results. Garden chervil (Anthriscus cerefolium) was characterized by lower concentrations of ascorbic acid (1.6-1.8 times), phenolics (2.2-2.5 times), flavonoids (1.8-2.2 times), total antioxidant activity (1-1.54 times) and dry matter content (2.4-4.9 times) than wild chervil (Anthriscus sylvestris) but demonstrated significantly higher levels of total dissolved solids. Significantly higher content of dry matter in leaves and especially stems of wild chervil correlates with low nutritional value of stems despite large total mass of plants compared to garden chervil. Contrary to wild chervil, Anthriscus cerefolium recorded unusually high concentrations of carotene in leaves and significantly lower levels of chlorophyll b. Seeds of garden chervil were also characterized by low antioxidant status contrary to wild chervil and seeds of curly parsley. High yield and significant nutritional value of garden chervil indicate important prospects of its wide-scale cultivation in Russia while Anthriscus sylvestris plants seem to be important in breeding processes.