The results of a comparative study of the influence of mineral and organic fertilizers - N16P16K16, Nanoplant, Hydrohumate, and Ecosil - on the state of the antioxidant complex of early-ripening (Northcountry, Croaton) and mid-ripening (Bluecrop, Northland) varieties of tall blueberries in an experimental culture on a low-lying peat bog in the Central agroclimatic zone of Belarus are presented. A significant dependence of changes in the level of their antioxidant and enzymatic activity on the type of fertilizers and the genotype of plants is shown. In most varieties, the increase in mineral nutrition contributed to an increase in the antioxidant activity level up to 28 %, the most significant when using Nanoplant and Hydrogumate. Revealed a distinct antagonism in changing the activity of peroxidase and catalase, on the one hand, and polyphenol oxidase, on the other: it increases synchronously in the first pair of enzymes to 77 and 30 % in varieties Northcountry, 171 and 152 % in the variety Croaton, 137 and 182 % in the variety Bluecrop and to 122 % of varieties for the Northland, against a preferential decrease in the activity of polyphenol oxidase in 13-55 %.In most cases, the tested agricultural practices have contributed to raising the general level oxidase activity of blueberry fruit. Especially in Croaton and Bluecrop varieties, by 30-310 %, with the highest efficiency of organic fertilizers, especially Hydrohumate. Nanoplant treatments had an inhibitory effect on the general level oxidase activity in Northcountry and Northland varieties and a stimulating effect in Croaton and Bluecrop varieties.

The results of studies on the presence in the seeds of legumes and cereals of protein inhibitors that are active against animal proteinases (trypsin) and exogenous peptidases of phytopathogenic microorganisms are presented. It has been shown that secreted proteolytic enzymes of the studied phytopathogens are mainly represented by cysteine proteinases, to a lesser extent, serine and aspartane proteinases are present. It has been established that a close positive correlation between plant resistance to pathogens is observed not with well-known and widespread trypsin inhibitors, but with the activity of inhibitors directed against exogenous peptidases secreted by fungal pathogens of the genus Fusarium , Colletotrichum and Helminthosporium . The results obtained in the course of the work can be used in breeding and genetic studies on the creation of varieties and types of crops with increased resistance to pathogenic microflora and insect pests, as well as to create protective preparations.

The article deals with the results of a biennial (2017–2018) comparative study of physico-chemical and agrochemical properties of the residual layer of a peat deposit under the plantation of two-year virginal plants of model Vaccinium corymbosum varieties (Northcountry, Bluecrop and Northland) on a recultivated developed lowland peat deposit under introduction of complete mineral fertilizer (‘Rastvorin’ brand ‘B’, N16P16K16), microfertilizer (Nanoplant-8, including eight trace elements: Co, Mn, Cu, Fe, Zn, Cr, Mo and Se) and organic fertilizers (Ekosil and Gidrogumat). In all variants of the experiment in both years of observations during the growing season in the root-inhabited layer, an increase relative to the initial level of the content of hydrolysable nitrogen and exchange potassium was found against the background of a decrease in the content of mobile phosphorus. In the first season, a slight increase in the level of hydrolytic acidity was registered, while the amount of absorbed bases decreased against the background of opposite changes in these indicators in the second season. In the first year of application of fertilizers by the end of the season, a significant enrichment of the substrate with mainly nitrate form of nitrogen and exchange potassium was established, with no noticeable changes in the content of mobile phosphorus. In the second year of application of fertilizers, there was a replenishment of ammonium nitrogen reserves with a predominant depletion of nitrate nitrogen, mobile phosphorus and exchange potassium (the greatest with Nanoplant and organic fertilizers treatment), which is due to the most intensive expenditure on the formation of the aboveground phytomass of experimental plants.

Приведены результаты двулетнего сравнительного исследования в опытной культуре на рекультивируемом участке выработанного низинного торфяника в центральной агроклиматической зоне республики влияния полного минерального (N16P16K16) удобрения («Растворин» марки «Б»), а также созданных в институтах НАН Беларуси новых экологичных препаратов - микроудобрения Наноплант-8, включающего 8 микроэлементов - Co, Mn, Cu, Fe, Zn, Cr, Mo, Se, и органических удобрений Экосил и Гидрогумат на физико-химические и агрохимические свойства остаточного слоя торфяной залежи под посадками генеративных растений сортов Northcountry, Bluecrop и Northland голубики высокорослой (V. corymbosum L.). Установлено, что во всех вариантах опыта, включая контроль, в течение вегетационного периода происходило повышение в субстрате уровня гидролитической кислотности в 1,6-3,0 раза, а также снижение количества поглощенных оснований и степени насыщенности ими поглощающего комплекса соответственно в 1,4-3,7 и 1,3-2,1 раза, сочетавшееся в первом сезоне с увеличением в 1,6-9,2 раза, а во втором, напротив, со снижением в 1,1-14,2 раза содержания доступных форм основных элементов питания, особенно нитратного азота. При этом в оба сезона на фоне выраженных генотипических различий в степени воздействия опытных растений на агрохимические свойства субстрата, использование Нанопланта и органических удобрений способствовало сопоставимому с полным минеральным удобрением и даже более выраженному обогащению субстрата относительно контроля нитратным азотом при обеднении аммонийным, сочетавшимися с неоднозначными изменениями в содержании других элементов в первом сезоне, а также с преимущественной активизацией накопления подвижного фосфора и истощением запасов обменного калия во втором. The article deals with the results of a biennial comparative study of physico-chemical and agrochemical properties of the residual layer of a peat deposit under the plantation of generative plants of model Vaccinium corymbosum varieties (Northcountry, Bluecrop and Northland) on a recultivated developed lowland peat deposit under introduction of complete mineral fertilizer («Rastvorin» brand «B», N16P16K16), microfertilizer (Nanoplant-8, including 8 trace elements: Co, Mn, Cu, Fe, Zn, Cr, Mo and Se) and organic fertilizers (Ekosil and Gidrogumat). In all variants of the experiment (and in the control version), during the growing season there was an increase in the level of hydrolytic acidity in the substrate (1,6–3,0 times), a decrease in the number of absorbed bases and the degree of saturation of the absorbing complex with them (by 1,4–3,7 and 1,3–2,1 times, respectively). In the first season, an increase of 1,6–9,2 times was noted, and in the second, on the contrary, a decrease of 1,1–14,2 times in the content of available forms of basic nutrients, especially nitrate nitrogen. In both seasons, the use of Nanoplant and organic fertilizers contributed to the enrichment of the substrate with the nitrate form of nitrogen comparable to the effect of complete mineral fertilization (and sometimes more pronounced), with a decrease in its ammonium form. The content of other nutrients in the first season characterized by ambiguous changes, while in the second season the accumulation of mobile forms of phosphorus was increased and the reserves of exchangeable potassium were depleted.

Приведены результаты сравнительного исследования влияния минеральных и органических удобрений – N16P16K16, Нанопланта, Гидрогумата и Экосила на состояние антиоксидантного комплекса плодов сортов Камчадалка и Ленинградский Великан жимолости съедобной на выработанном торфянике в центральной Беларуси. Установлена существенная зависимость изменения уровня их антиоксидантной и ферментативной активности от вида удобрений и генотипа растений. Усиление минерального питания способствовало повышению уровня АОА до 19%, наиболее значительному при использовании Гидрогумата. Выявлен отчетливый антагонизм в изменении активности ПО и КАТ, с одной стороны, и ПФО, с другой, по сравнению с контролем, проявившийся в синхронном ее увеличении у первой пары ферментов до 69 и 303% у сорта Камчадалка и до 228 и 506% у сорта Ленинградский Великан на фоне преимущественного снижения активности ПФО на 13-38% при наиболее выраженном проявлении обозначенных эффектов при использовании Нанопланта и Гидрогумата преимущественно у первого таксона. При этом испытываемые агроприемы обусловливали повышение, по сравнению с контролем, общего уровня оксидазной активности плодов на 31-331% у первого таксона и на 196-612% у второго при наибольшей результативности использования Нанопланта и наименьшей - полного минерального удобрения. The results of a comparative study of the influence of mineral and organic fertilizers (N16P16K16, Nanoplant, Hydrohumate, and Ecosil) on the state of the antioxidant complex of fruits of the honeysuckle varieties (‘Kamchadalka’ and ‘Leningrad Giant’) in an experimental culture on a worked-out low peat bog in the conditions of Central agro-climatic zone of Belarus are presented. A significant dependence of changes in the level of their antioxidant and enzymatic activity on the type of fertilizers and plant genotype was established. The increase in mineral nutrition led to an increase the level of antioxidant activity up to 19% (the most significant under the application of Hydrogumate). The increase in mineral nutrition led to an increase the level of antioxidant activity up to 19% with the most significant infl uence on it the application of Hydrohumate. There was a clear antagonism in the change in the activity of peroxidase and catalase, on the one hand, and polyphenol oxidase, on the other, in comparison with the control. This was manifested in its synchronous increase in the first pair of enzymes to 69 and 303% (in the ‘Kamchadalka’ variety) and to 228 and 506% (in the ‘Leningrad Giant’ variety), against the background of a predominant decrease in the activity of polyphenol oxidase by 13–38%. The most pronounced manifestation of the indicated effects registered after Nanoplant and Hydrohumate treatments mainly in the first taxon. At the same time, the tested agricultural techniques caused an increase in the overall level of oxidase activity by 31-331% in the first taxon and by 196-612% in the second taxon. The highest influence on the overall level of oxidase activity provides the treatment of Nanoplant and the lowest - using of complete mineral fertilizer.

The depressing effect of electromagnetic radiation from power lines on morphometric and biochemical indicators of winter wheat and wild plant species has been established.Levelling of the inhibitory effect of power lines was observed as far away from the radiation source.The role of components of proteolysis system and lectins in plant adaptation to stress was noted.

Pre-harvesting germination of grain causes a considerable loss and it is one of the reasons for the decline of sowing and technological properties of grain. In this regard, the aim of this work was to elucidate the role of hydrolytic enzymes in the grain crop sustainability to germination in the ear. The object of the study were di- and tetraploid forms of rye and hexaploid forms of triticale and secalotriticum. The research allowed to select a stable and productive form of cereals to evaluate the resistance to grain germination for assessment of resistance to germination of grain at the root. It is shown that the germination of the grain at the root is affected by the ploidy of rye and the type of cytoplasm from heteroplasmic triticale. It is shown different levels of activity of proteolytic and amylolytic enzymes in the studied genotypes of cereals. Winter triticale had a marked higher level of activity of neutral, alkaline protease and α-amylase. Variation in the level of BAPase activity is 7.15– 24.4 EA/g. a. d. m. and α-amylase activity – 92 –118.7 mg/ml∙h. It is shown the close correlation between the activity of alkaline BAPase, α-amylase and resistance to the cereal grain germination in the ear. Heterogeneity of an electrophoretical range of proteins at the studied genotypes of rye and triticale is shown. The obtained data make a contribution to clarification of the reasons underlying the resistance of cereal cultures to germination of grain at the root and open possibilities of identification of their markers for use in selection.

The activities of secreted and mycelial inhibitors of proteolytic enzymes from fungi of the order Hypocreales have been investigated. Inhibitors of bromelain, papain, and trypsin of low molecular mass (about 1 kDa) and a subtilisin proteinaceous inhibitor with molecular mass of 45 kDa were revealed in the culture liquid of the fungus Tolypocladium cylindrosporum. The subtilisin inhibitor from T. cylindrosporum has antibiotic properties, significantly decreased the activity of purified bacterial enzymes, and prevented the growth of the bacterium Pseudomonas sp. Data suggesting the existence in fungi of the Hypocreales order of two pools of peptidase inhibitors have been obtained.

Galega orientalis Lam. is a fodder crop with a number of important traits, including the early beginning of vegetation, fast growth, high productivity and nutritiousness. For its cultivation, the doses of mineral N are reduced due to active symbiotic N-fixation, resulting in the decrease of nitrogen content in the fodder and livestock production. Lectins and proteinase inhibitors, as anti-nutrients, affect the fodder quality negatively. But the distribution and activity of proteolytic factors and lectins in Galega orientalis are not still clarified enough. We conducted the chemical investigation of leaves and seeds in 19 varieties and samples of Galega orientalis, originated mainly from the Eastern Europe. The activity of neutral and alkaline proteinases, tripsin inhibitors, lectin phytohemagglutination (PHA), as well as the protein content, composition and digestibility were examined. In total, the parameters varied significantly. The tested Galega varieties are the highly valuable fodder crop. Particularly, the content of proteins and essential amino acids in plants was high. The amino acid composition, necessary for the young growing animals, was revealed. In contrary, the content of tripsin inhibitors and lectins was not sufficient. The inhibitors were more active in the plants which began their vegetation later, and PHA was higher in the plants with early and intermediate beginning of vegetation. The characteristic electrophoretic patterns of seed proteins were also shown.

The response of the components of a protease-inhibitor system of legume and cereal crops to stress factors was studied. It was found that salinization, heavy metal ions, and phytopathogenic flora inhibit the activity of neutral, acidic, and alkaline proteases at early stages of seed germination, the degree of the inhibition of the endoprotease activity being dependent on the index of tolerance of legume and cereal crops. It was shown that, in response to unfavorable conditions, accumulation of trypsin inhibitors occurs, which is accompanied by the appearance of new protein components, as indicated by electrophoresis. The results confirm the presumption that serine protease inhibitors are involved in the response of plants to stress factors.

The main proteinase of the filamentous fungus Colletotrichum gloeosporioides causing anthracnoses and serious problems for production and storage of agricultural products has molecular mass of 57 kD and was purified more than 200-fold to homogeneity with the yield of 5%. Maximal activity of the proteinase is at pH 9.0–10.0, and the enzyme is stable at pH 6.0–11.5 (residual activity not less than 70%). The studied enzyme completely kept its activity to 55°C, with a temperature optimum of 45°C. The purified C. gloeosporioides proteinase is stable at alkaline pH values, but rapidly loses its activity at pH values lower than 5.0. Addition of bovine serum albumin stabilizes the enzyme under acidic conditions. Data on inhibitor analysis and substrate specificity of the enzyme allow its classification as a serine proteinase of subtilisin family. It is demonstrated that the extracellular proteinase of C. gloeosporioides specifically effects plant cell wall proteins. It is proposed that the studied proteinase — via hydrolysis of cell wall — provides for penetration of the fungus into the tissues of the host plant.

Specific features of changes in the contents of free and bound abscisic acid (ABA) and the activities of neutral and alkaline proteinases and trypsin inhibitory proteins were determined in the embryonic axis and cotyledons of the common bean (Phaseolus vulgaris L.) after drying. The changes in ABA content, observed following the loss of 5% seed weight, were regarded as an adaptive reaction to stress, whereas the corresponding changes after the loss of 10% of the seed’s weight, was regarded as a result of a pathological disturbance of ABA metabolism. Both drying modes had a negative effect on the state of the proteinase-inhibitory system, as was apparent from the disruption of the regular inverse correlation between the activities of proteinases and serine proteinase inhibitory proteins. A comparison of the dynamics of these characteristics with the buildup of water stress demonstrates an inverse correlation between the content of free ABA and the activity of the proteinases studied. This suggests a potential inhibitory effect of this hormone on the function of the hydrolases in question in the germinating seed.

Physicochemical and functional characteristics of plant protein proteinase inhibitors as antistress biopolymers were studied to determine the mechanisms for plant resistance to phytopathogens and to obtain disease-resistant cereal and leguminous cultures. The activity of trypsin, chymotrypsin, and subtilisin inhibitors varied in monocotyledonous and dicotyledonous cultures. Study varieties of leguminous and cereal cultures were shown to contain endogenous inhibitors specific to proteinases of phytopathogenic fungi Fusarium, Colletotrichum, Helminthosporium, and Botrytis. These inhibitors were characterized by species specificity and variety specificity. Protease inhibitors from buckwheat seeds inhibited proteases of fungal pathogens and suppressed germination of spores and growth of the fungal mycelium. Our results suggest that proteinaceous inhibitors of proteinases are involved in the protective reaction of plants under stress conditions.

The amounts of protein and the activities of the proteinase (trypsin) inhibitors of 16 varieties of pea have been studied. The amount of protein ranged from 19.3 to 25.2% and the amidase activities of the trypsin inhibitors from 18 to 40.8 IU. It was found that the electrophoretic spectrum of the inhibitor-containing fraction of the pea seed protein consisted of 12–16 components with molecular masses of 14–89 kDa. Features of the electrophoretic spectrum of some varieties of pea have been established.