Inoculation Of Seeds Research Articles

Bacillus thuringiensis Effect on the Vegetative Development of Cotton Plants and the Biocontrol of Spodoptera frugiperda

Bacillus thuringiensis (Bt) is used worldwide as a tool for controlling lepidopteran pests. Recent studies have demonstrated the possibility of its use as an endophytic organism, controlling insects and promoting plant growth. In this aspect, strains of Bt toxic to lepidopteran pests were inoculated both onto seeds and into cotton plants and were assessed for effectiveness in controlling Spodoptera frugiperda and its effect on promoting plant growth. It was observed that the results obtained from the interaction between the Bt strains (S1450 HD-1, S1905, S2122, S2124) and the cotton genotypes (BRS 8H, BRS Aroeira and BRS 286) showed different growth responses. The results also showed that all the strains may not be suitable to explore the biological control mechanism without undermining plant health. Therefore, the strain S2122, the BRS 8H genotype and seed inoculation were selected to continue the tests by using two concentrations of the bacterium. The results of Bt strain inoculation in seeds and into cotton plants showed that, although plant height, number of leaves, and development stage were influenced by Bt inoculation, overall, there was no significant improvement in the plant growth. The plants that were inoculated with Bt also interfered in the weight of Spodoptera frugiperda, however, did not cause the pest mortality. The collected results suggest that there is a close relationship between the Bt strain and the cotton crop and that colonizing mechanism of the bacterium can be useful in situations that there is an inefficiency of the control measures, since the endophytic Bt makes the pest more susceptible to be controlled by other practices, improving management effectiveness.

Moniliella spathulata, an oil-degrading yeast, which promotes growth of barley in oil-polluted soil

The yeast strain Moniliella spathulata SBUG-Y 2180 was isolated from oil-contaminated soil at the Tengiz oil field in the Atyrau region of Kazakhstan on the basis of its unique ability to use crude oil and its components as the sole carbon and energy source. This yeast used a large number of hydrocarbons as substrates (more than 150), including n-alkanes with chain lengths ranging from C10 to C32, monomethyl- and monoethyl-substituted alkanes (C9–C23), and n-alkylcyclo alkanes with alkyl chain lengths from 3 to 24 carbon atoms as well as substituted monoaromatic and diaromatic hydrocarbons. Metabolism of this huge range of hydrocarbon substrates produced a very large number of aliphatic, alicyclic, and aromatic acids. Fifty-one of these were identified by GC/MS analyses. This is the first report of the degradation and formation of such a large number of compounds by a yeast. Inoculation of barley seeds with M. spathulata SBUG-Y 2180 had a positive effect on shoot and root development of plants grown in oil-contaminated sand, pointing toward potential applications of the yeast in bioremediation of polluted soils.Key points• Moniliella spathulata an oil-degrading yeast• Increase of the growth of barley

СИМБИОТИЧЕСКАЯ АКТИВНОСТЬ ПОСЕВОВ ЛЮЦЕРНЫ В ЗАВИСИМОСТИ ОТ ТИПА АЗОТНОГО ПИТАНИЯ

The issue of the use of mineral forms of nitrogen for legumes is still a source of debate among scientists. Under the environmental conditions of the foothill zone of RNO-Alania, the field experiments were laid to study the activity of the symbiotic system and the productivity of the alfalfa depending on the type of nitrogen nutrition and the presence of a virulent active strain of rhizobia. The research was carried out in 2017– 2019. Soil – chernozems leached. Objects: crops of Medicago varia Mart.; industrial strain of rhizotorphin 425a; inoculum of high-mountain strains of nodule bacteria; starting doses of nitrogen fertilizers. The dimensions of the symbiotic apparatus were studied according to the G.S. Posypanov method. The specific activity of symbiosis was 4.2 to 9.0 mg/kg. The maximum amount of air nitrogen (456.1 kg/ha) for three years of experiments was fixed by the symbiotic system of alfalfa in the variant with pre-sowing seed inoculation with high-mountain strains of nodule bacteria. This indicates their higher activity and competitiveness compared to the industrial strain of rhizotorphin 425a and indigenous strains of rhizobia from the pre-mountain zone of RNO-Alania. Mineral forms of nitrogen significantly inhibited the activity of the symbiotic system. As a result, the amount of fixed nitrogen decreased by 3.5–9.0 %. In the pre-mountain zone, under natural conditions, the growth and development of plants were provided with atmospheric nitrogen by 66 %, the rest of the need for the element (34 %) they satisfied with soil nitrogen. The maximum involvement of molecular nitrogen of the atmosphere in the biological cycle was distinguished by the variant with pre-sowing inoculation of seeds by virulent active strains of rhizobia, in which the share of air nitrogen participation in plant nutrition averaged 71–73 % over the three years of research.

Resistance of Two-Rowed Barley Cultivars and Collection Accessions to False Loose Smut in Western Siberia

False loose smut caused by the fungus Ustilago nigra Tapke causes significant damage to barley crops in Russia. The aim of this work was to estimate the false loose smut resistance in spring double-row barley varieties created by the Omsk Agrarian Research Center and samples from the Collection of the Vavilov All-Russia Institute of Plant Genetic Resources (VIR) in Western Siberia. Cultivars were assessed in the field in 2016–2019 according to common methods. The artificial inoculation of seeds with U. nigra teliospores was carried out before sowing. The damage to cultivars significantly varied, which was due to contrasting weather conditions during periods critical for plant infection. Stable resistance to disease was observed for cultivars Omsky 91 and Sasha, while damage to other cultivars of Omsk breeding increased. The collection cultivars of Russian and Western European breeding showed high resistance to false loose smut under conditions favorable for infection, as well as in drought with high temperatures. Ukrainian and Latvian cultivars showed high resistance to infection under conditions of high humidity and low temperature. High resistance under contrasting conditions was observed for cultivars Vorsinsky 2, Yasny, Vakula, Zadel 3, Yastreb, Inklyuziv, and Vzirez. The best combination of resistance to the disease and yields were demonstrated by cultivars Vorsinsky 2, Zernogradsky 770, Vakula, Vzirets, and Inklyuziv. These cultivars are promising to be used as sources of false loose smut resistance for barley breeding in Western Siberia.

WAYS TO INCREASE YIELD OF CHICKPEAS

The analysis of literary sources showed that interest in chickpeas is increasing, sown areas under this crop are expanding, and technological features for chickpea cultivation are changing. The yield of chickpea seeds to a large extent depends on the biological characteristics of the variety, fertilizers, compliance with the timing and methods of sowing, inoculation of seeds and the like. Much attention should be paid to the system of protection of chickpea agrocenoses from harmful organisms. Weak competition of chickpea plants with weeds is primarily due to the peculiarity of the development of this culture in the early stages, when there is an intensive development of the root system and slow - the aboveground part. In these early stages of their development, chickpea plants are not yet able to fully compete with weeds. The latter, on the contrary, are serious competitors, as they actively use nutrients, moisture and shade plants. High selectivity and herbicidal activity in chickpea crops were shown by soil preparations: Stomp, 33% k.e. (4.0 l / ha); Harness, 90% (1.5–3.0 l / ha); Optima frontier (0.8– 1.0 l / ha). Weed reduction was 85–90% and yield increase was 0.71–0.82 t / ha. Of the post-emergence herbicides in chickpea crops in conditions of mixed weed type, it was advisable to use Pulsar (0.5-0.9 l / ha) and Pivot (0.5-0.8 l / ha). Weed loss was 81.0–82.0% and yield increase was 0.72–0.76 t / ha. When using different herbicides, the yield of chickpea grain was in the range from 1.26 to 1.44 t / ha. The presence of chickpeas in crops leads to severe inhibition, especially in the initial stages of vegetation. The most effective and economically feasible at present is the use of a tank mixture of herbicides Harnes + Gezagard 500 FM (2.0 l/ha + 3.0-4.0 l/ha) which makes it possible to control a wide range of weeds and extend the duration of the protective shield preparations. Chickpea seeds ripen fairly evenly throughout the plant, the beans do not crack or crumble, the plants do not lie down, so when harvested by direct combining there are no problems. The growing season in chickpeas lasts 80-120 days, depending on the variety and growing conditions, so it is harvested in late July or early August after harvesting cereals. The yield of chickpea seeds varies in the range 1.4–2.7 t/ha, and with proper technology and climatic conditions it can be 2.5–3.5 t/ha. Key words: chickpeas, agrocenosis, technology, mineral fertilizers, weeds, herbicides, biological products, productivity.

SUBSTANTIATION OF THE ADAPTIVE SORTING TECHNOLOGY OF GROWING LEGUMINOUS CROPS IN THE RIGHT-BANK FOREST STEPPE OF UKRAINE

The relevance of the conducted research is based on the tasks of the applied research of Vinnytsia National Agrarian University on the topic: «Development of methods for improving the technology of growing leguminous crops using biofertilizers, bacterial preparations, foliar fertilizers and physiologically active substances». Analysing the literature sources various technological methods of growing leguminous crops for providing the rational use of natural agricultural potential, which will further increase the sown area of major legumes, which are of strategic importance, have been evaluated. The article analyses the varietal diversity of leguminous crops included in the State Register of Plant Varieties of Ukraine. High-yielding varieties for the Right-Bank Forest-Steppe of Ukraine of soybeans – Azymut, Holubka, sowing peas – Tsarevych and Prystan have been chosen for the study; white lupine – Veresnevyi, Chabanskyi; narrow-leaved lupine – Olimp, Peremozhets; chickpeas for sowing – Skarb, Pegas. According to the group of ripeness, early-, medium- and medium-early-ripening varieties of legumes are selected, which have been distinguished among others for their high grain and protein productivity. It has been determined that the types of legumes in terms of set basic economic-valuable peculiarities have significant advantages such as resistance to adverse environmental factors, pests and manufacturability. The field experiments have shown that the combination of inoculation of seeds with a bacterial preparation and treatment of plants for vegetation with a retardant has had a positive effect on increasing the yield of the crops. For the years of the conducted researches, the maximum seed yield in the leguminous crops has been determined. Thus, in sowing peas the most productive type was Prystan (2.6 t/ha), white lupine – Chabanskyi (3.4 t/ha), narrow-leaved lupine – Peremozhets (2.6 t/ha), chickpea – Skarb. 3.0 t/ha) and in soybeans – Azymut (2.6 t/ha). The largest increases in grain productivity were obtained by treating the seeds with the bacterial preparation Rhizohumin and spraying the crops with chlormequat chloride retardant in the budding phase. Keywords: leguminous crops, variety, quality, yield, growing area.

Эффективность применения органоминерального удобрения «Биоклад» на смешанном посеве овса с горохом в условиях лесостепной зоны РСО-Алания

Abstract. The authors present the results of the application of complex organo-mineral fertilizer “Bioklad” on mixed sowing of oats with peas in the conditions of the forest-steppe zone Republic of North Ossetia-Alania. The purpose of the work is to study the effectiveness of the use of the organomineral fertilizer “Bioklad” on the yield and nutrition of mixed sowing of oats with peas in the conditions of the forest-steppe zone Republic of North Ossetia-Alania. Methods. Studies on the tasks were carried out in 2016–2018 at the experimental site of the North Caucasus Research Institute of Mountain and Foothill Agriculture – branch of the Federal Center “Vladikavkaz Scientific Center of the Russian Academy of Sciences” in the conditions of the forest-steppe zone Republic of North Ossetia-Alania according to generally accepted methods. The soil of the experimental plot is medium-power heavy loamy leached chernozem, lined with pebbles. Results. The use of fertilizer “Bioklad” had a significant impact on the timing, fullness of shoots and the density of standing plants up to harvest. The field germination rate for peas varied between 70,5 and 72,4 %, while the oat rate was 76,4 to 80 %. The option with seed inoculation was highlighted. According to the dynamics of the height of the plants also stood out the option with the inoculation of seeds. The use of complex fertilizer “Bioklad” had a positive effect on the yield and quality of the green mass of oats with peas. The largest amount of phytomass was obtained under the variant with inoculation of seeds – 283,3 c/ha, which is higher than the control version at 68,3 c/ha. In terms of the content of digestible protein, the harvest of the mixture of oats with peas exceeded the zootechnical norm, the yield from one hectare reached 6,0–6,9 c/ha, against 5,2 c/ha in control, which per feed unit was 113,7–119,9 g. The collection of feed units amounted to 50,02–60,68 kg/ha, and in the control 44,23 kg/ha, feed protein units, respectively: 55,01–64,84 kg/ha; 48,12 kg/ha. Scientific novelty. For the first time in the conditions of the forest-steppe zone Republic of North Ossetia-Alania studied the effect of complex organomineral fertilizer “Bioklad” on plant growth processes, formation of green mass, quality of products in a two-component mixture (oats + peas).

Dynamics of alfalfa leaf area depending on nitrogen feeding type

The results of field studies for 2017-2019 of dynamics of assimilation surface of alfalfa crops depending on the type of nitrogen nutrition and symbiotic activity of crops are given. Tests with Medicago varia Mart. were carried out in environmental conditions of the pre-mountain zone of RNO-Alania (540 meters above sea level) on the black earth leached with close occurrence of pebbles. Mineral and symbiotrophic types of nitrogen nutrition of alfalfa plants were compared. The experience scheme included options: control - natural soil fertility; In-1800 - treatment of seeds with inoculum of strains of nitrogen-fixing bacteria selected in high mountain conditions (1800 m above sea level); Strain 425a - inoculation of seeds with industrial strain rhizotorphin (strain 425a); N30 - starting nitrogen dose; N30+In is the joint use of highland strains of bacteria and starting doses of nitrogen. Seeds were treated with the strains studied before sowing. Mineral nitrogen fertilizers were introduced annually early in spring in the form of starting doses. It has been established that the minimum areas of leaves on all variants are observed in the first year of life, in the second year of use of crops the maximum assimilation surface is formed in plants, in the third year - indicators gradually decrease. Every year, the maximum assimilation surface is formed by perennial leguminous herbs to the budding stage - the beginning of flowering (bevel has fallen). The dynamics of leaf surface build-up is directly proportional to the activity of symbiotic relationships with rhizobias. In variants with the highest symbiotic activity (In-1800 and N30+In) the area of leaves reaches maximum values and exceeds 40 thousand m ?/ha in certain years.

Improvement of spring wheat cultivation technologies for sustainable development of agriculture in the Volga region

The use of synthetic biologically active substances in the technology of cultivation of spring wheat contributes to an increase in its productivity, stable, high yields, and, consequently, to a sustainable and effective development of agriculture. In the course of our research, we studied the effect of pre-sowing seed treatment with selenium-containing biologically active substances with varying agrophones on the production process of spring wheat in the conditions of leached chernozems of the Saratov Right Bank. The stimulating effect of biologically active substances (selenochromylium perchlorate and selenochromene) on the sowing qualities of spring wheat (Belyanka and Prokhorovka varieties) was established. A significant increase in the yield of the studied varieties of soft spring wheat was during inoculation of seeds with solutions of selenochromylium perchlorate and selenochromene. The application of biologically active substances, especially selenium-containing substances, increased the payback of mineral fertilizers with an additional harvest. The selenochromene preparation on the crops of the Prokhorovka variety was the most effective. It is shown that the application of biologically active substances is an effective way to increase the productivity of agricultural crops.

Peculiarities of leaf area formation and yield structure of ‘Antonina’ lentil variety depending on the elements of technology

Purpose. To reveal the peculiarities of leaf area formation and a structure of lentils variety ‘Antonina’ yield depending on the elements of cultivation technology: ino culation with nitrogen-fixing and phosphate-solubilizing microorganisms and the use of foliar growth stimulants.Methods. Field, laboratory. The experimental scheme included inoculation of seeds with nitrogen-fixing microorganisms (Ryzogumin), application of phosphate-solubili zing microorganisms (Polimixobacteryn and Biophosphoryn) into the row zone, and foliar feeding with a growth stimulator (Alga 600).Results. The results of studies of the leaf area formation peculiarities and the structure of lentils yield depending on the influence of cultivation technology elements are given in the article. It was found that the maximum indicators of the leaf area were formed by lentils in the flowering phase, which on average in the experiment was at the level of 37.5 thousand m2/ha, and in the control variant – only 32.0 thousand m2/ha. By inoculating the seeds with Rhyzogumin, applying phosphate-solubilizing biopreparation and foliar feeding, we obtained the maximum parameters of the leaf surface of lentil plants in the experiment. Thus, in the variant of inoculation with Rhyzogumin, application of Biophosphoryn and treatment with Alga 600 lentil plants formed a leaf area of 40.3 thousand m2/ha. However, due to the use of the phosphate-solubilizing biopreparation Polimixobacteryn and Alga 600 on the background of seeds inoculation with Rhyzogumin, the leaf area was formed at the level of 39.9 thousand m2/ha.Conclusions. When the seeds were treated with nitrogen-fixing microorganisms (Rhyzogumin) and phosphate-solubilizing bacteria (Polimixobacteryn and Biophosphoryn), the yield of lentils increased significantly. Thus, in the experimental plots in the variants with Ryzogumin + Polimixobacteryn the yield was – 1.64 t/ha, and in the combination Ryzogumin + Polimixobacteryn + growth stimulator Alga 600 the yield of lentils was – 1.90 t/ha. Seed inoculation had a positive effect on plant height. The best results were obtained when the seeds were treated with Ryzogumin in combination with Biophosphorin and Polimixobacteryn – 44.5 and 44.1 cm, respectively.

Inoculation of Pseudomonas mutant strains can improve growth of soybean and corn plants in soils under salt stress

In the last decades, the applications of Plant Growth Promoting Rhizobacteria (PGPR) as inoculants for enhancing crops yield under different stress conditions have reached enormous interest. Pseudomonas putida KT2440 is a well-known rhizobacteria capable of colonizing roots of agronomically important crops. This work aims to evaluate three P. putida KT2440 mutants (mus-20, mus-42, and EU206), which have non-biofilm producing and exopolysaccharide overproducing phenotypes, for their potential as PGPR on soybean and corn plants under saline stress. Experimental studies showed that KT2440 and its mutants were effective in three main PGPR properties: solubilization of phosphates and synthesis of indolic compounds and siderophores. Notably, indolic compounds synthesis increased in mus-20 and EU206 strains. Furthermore, all evaluated strains were tolerant to saline stress. Bacterial inoculation of soybean and corn seeds was effective both in vitro and in vivo tests, even at high salt concentrations (80 and 120 mM NaCl). Among mutant bacteria, EU206 strain seems to be the most efficient PGPR by significantly increasing seed germination, shoot and root lengths, and fresh and dry weights of plants compared to non-inoculated controls, in in vivo tests under saline condition, mainly in both corn plants. These results suggest that inoculation with the P. putida KT2440 mutant strains is an appropriate strategy to enhance the growth of soybean and corn plants, so they might be employed for promoting regional crops growth at field scale using natural saline soils.

Effect of Azospirillum zeae and Seed Priming with Zinc, Manganese and Auxin on Growth and Yield Parameters of Wheat, under Dryland Farming

In this study, field experiments with wheat (Triticum aestivum L.) were conducted consecutively for 2 years. The main objective was to determine (1) effect of seed priming with auxin (IAA), zinc (Zn) or manganese (Mn) on growth and yield parameters of wheat under dry land farming; (2) influence of on-farm priming with Azospirillum under field conditions. In this study, the response of dryland wheat yield to soaking seeds in water, 2 ppm IAA, 0.2% Mn solution and 0.2% aqueous solution of Zn with or without Azospirillum zeae inoculation was investigated under field condition. Total grain yield was significantly enhanced for water primed seeds i.e., 1273 kg ha−1 (6.8%) or seeds primed with IAA, as compared to 1191 kg ha−1 in plants from non-primed seeds. Difference in grain yield between priming with water and 2 ppm IAA was not significant when compared with 1372 kg ha−1 (15%) for seeds primed with 0.2% Mn solution and 1440 kg ha−1 (20%) for seeds primed with 0.2% Zn solution. Grain yield was significantly increased for plants inoculated with Azospirillum, 1411 kg ha−1 (8%) as compared to 1191 t ha−1 for non-Azospirillum-inoculated seeds. Yield parameters, i.e., tiller no. per m−2, grain number per spike, and 1000-grain weight, were all significantly affected by priming treatments and Azospirillum inoculation. Grains with the high nitrogen and phosphorous content were recorded for the treatment where seeds were primed with Zn and inoculated with Azospirillum. In the present study, inoculation of wheat seeds followed by priming is a significant approach to enhance grain yield and grain nutrients (N and P) content.

New Bacterial Strains of Рseudomonas laurentiana: Promising Agents for Agrobiotechnology

Bacterial strains ANT 17 and ANT 56, antagonistic to plant pathogenic fungi Bipolaris sorokiniana, were isolated from activated sludge. Physiological, biochemical, and culture morphological properties and analysis of the 16S rRNA gene sequence and composition of fatty acids of cell walls of strains ANT 17 and ANT 56 supported its classification as the species Pseudomonas laurentiana. It was shown that strains P. laurentiana ANT 17 and P. laurentiana ANT 56 possess a set of properties characteristic of PGP (plant growth-promoting) microorganisms: they exhibit antifungal activity against phytopathogenic micromycetes and are capable of decomposing phosphates and synthesizing phytohormonal substances. Inoculation of cucumber, tomato, and cabbage seeds had a beneficial effect on their germination. Presowing treatment of wheat seeds under conditions of a natural infectious background with an inoculum of the isolated bacterial strains contributed to a decrease in the spread of fungi that cause root rot. The possibility of using strains P. laurentiana ANT 17 and P. laurentiana ANT 56 in biotechnology in order to increase the productivity of agroecosystems is suggested. The ability to stimulate the growth and development of plants for P. laurentiana strains is shown for the first time.

Phenazine-Producing Rhizobacteria Promote Plant Growth and Reduce Redox and Osmotic Stress in Wheat Seedlings Under Saline Conditions.

Application of plant growth promoting bacteria may induce plant salt stress tolerance, however the underpinning microbial and plant mechanisms remain poorly understood. In the present study, the specific role of phenazine production by rhizosphere-colonizing Pseudomonas in mediating the inhibitory effects of salinity on wheat seed germination and seedling growth in four different varieties was investigated using Pseudomonas chlororaphis 30-84 (wild type) and isogenic derivatives deficient or enhanced in phenazine production. The results showed that varieties differed in how they responded to the salt stress treatment and the benefits derived from colonization by P. chlororaphis 30-84. In all varieties, the salt stress treatment significantly reduced seed germination, and in seedlings, reduced relative water content, increased reactive oxygen species (ROS) levels in leaves, and in three of four varieties, reduced shoot and root production compared to the no salt stress treatment. Inoculation of seeds with Pseudomonas chlororaphis 30-84 wild type or derivatives promoted salt-stress tolerance in seedlings of the four commercial winter wheat varieties tested, but the salt-stress tolerance phenotype was not entirely due to phenazine production. For example, all P. chlororaphis derivatives (including the phenazine-producing mutant) significantly improved relative water content in two varieties, Iba and CV 1, for which the salt stress treatment had a large impact. Importantly, all P. chlororaphis derivatives enabled the salt inhibited wheat varieties studied to maintain above ground productivity in saline conditions. However, only phenazine-producing derivatives enhanced the shoot or root growth of seedlings of all varieties under nonsaline conditions. Notably, ROS accumulation was reduced, and antioxidant enzyme (catalase) activity enhanced in the leaves of seedlings grown in saline conditions that were seed-treated with phenazine-producing P. chlororaphis derivatives as compared to noninoculated seedlings. The results demonstrate the capacity of P. chlororaphis to improve salt tolerance in wheat seedlings by promoting plant growth and reducing osmotic stress and a role for bacterial phenazine production in reducing redox stress.

Sustainable production of common beans: inoculation, co-inoculation and mineral fertilization in early-cycle cultivars

Using sustainable management to maximize crop yield without increasing production costs is one of the great challenges of modern agriculture. This study aimed to evaluate the effect of nitrogen (N) supply management, associating inoculation with Rhizobium tropici, co-inoculation schemes with Azospirillum brasilense and mineral top-dressing fertilization, on the agronomic and qualitative performance of early-cycle common bean cultivars. The experiment was installed in a randomized block design, in a 2 x 12 factorial scheme (2 cultivars and 12 N supply management), with four repetitions. The N supply management consisted of the association of mineral fertilization with N (45 and 90 kg ha−1 of N in top-dressing), inoculation of seeds with Rhizobium tropici and co-inoculation of seeds and leaves with Azospirillum brasilense. The agronomic and qualitative performance of common bean was affected by the nitrogen supply management and by the cultivars, and the response was independent of the interaction between cultivars and N supply management. Except for plant dry mass, all variables analyzed showed maximum response in the treatment of seed inoculation with Rhizobium tropici, leaf-spray of Azospirillum brasilense and mineral top-dressing fertilization with 90 kg ha−1 of N, which led to a 27% increase in yield compared to the control. The cultivar IAC Imperador has a superior agronomic performance (grain yield = 2,840 kg ha−1) compared to IPR Curió (2,484 kg ha−1). The results demonstrated the feasibility of using co-inoculation with Azospirillum brasilense as a tool to increase yield, grain quality and sustainability in common bean production systems.

Coinoculação e uso de nitrogênio em cobertura na cultura da soja

A inoculação com bactérias do gênero Bradyrhizobium, ocasiona na rizosfera a formação estruturas especializadas na fixação biológica de nitrogênio, sendo descartada a aplicação na cultura da soja, uma vez que a relação simbiótica consegue suprir suas necessidades. O objetivo do trabalho foi avaliar a influência da inoculação bem como de níveis de nitrogênio em cobertura no crescimento, desenvolvimento e produtividade da soja. O experimento foi realizado na área experimental da Universidade Estadual de Mato Grosso do Sul – Unidade Universitária de Aquidauana. O delineamento experimental foi em blocos casualizados em esquema fatorial 4x4, com quatro repetições. Os tratamentos foram constituídos pela combinação entre inoculantes (Bradyrhizobium japonicum; Azospirillum brasilense; B. japonicum + A. brasilense; Controle sem inoculação) e quatro níveis de nitrogênio em cobertura na soja (0; 50; 100; 150 kg ha-1). A inoculação foi realizada antes da semeadura, já a aplicação do nitrogênio foi realizada no estádio V8, para tal, utilizou-se sulfato de amônio como fonte. Foram avaliados: população final de plantas, altura da planta, altura de inserção da primeira vagem, diâmetro do caule, número de vagens por planta, número de grãos por vagem, produtividade de grãos, massa de 1000 grãos. A inoculação de sementes de soja usando isoladamente ou em conjunto não interfere no desenvolvimento e produtividade de grãos da cultura da soja, assim o uso de nitrogênio mineral em cobertura é dispensável, pois não reflete em incrementos na produtividade de grãos da soja.

Продуктивність сортів сої залежно від інокуляції насіння бульбочковими й ендофітними бактеріями в умовах зрошення південного Степу України

Продуктивність сортів сої залежно від інокуляції насіння бульбочковими й ендофітними бактеріями в умовах зрошення південного Степу України

Economic analysis of irrigated bean production in function of nitrogen fertilization management and inoculation of seeds

The best period and method for the application of nitrogen fertilization, as well as the use of inoculation or not of bean seeds, are variables that can be of great value to the producer from an agroeconomic point of view when considering the selection of the correct irrigation management. So, the aim of this study was to perform an eco­nomic analysis of the irrigated bean, according to different fertilization managements and seed inoculation. The work was conducted in the municipality of Aquidauana-MS, Brazil in the experimental area of the State University of Mato Grosso do Sul, using the cultivar IAC Milênio with sowing during the winter season. The experimental was setup in a completely randomized block design with four replications. Nitrogen fertilization (sowing, cover and foliar) and seed inoculation (absence and presence) were used in the plots. For economic analysis of the irrigated common bean, calculation of the total production cost was performed, in function of the effective operational cost and the total operational cost. To determine the profitability of the treatments involved, the following values were calculated: gross revenue, net revenue, profitability index, equilibrium price and equilibrium productivity. The eco­nomic analysis response of the irrigated bean varied according to the different fertilization managements and inoculation of seeds, where nitrogen application at sowing and seed inoculation presented economic results. Alt­hough the cost of production varied little, the profitability indices of each treatment vary in function of the produc­tivity obtained. Nitrogen fertilization at sowing and inoculation of seeds with Rhizobium tropici provided increased net revenue for the common bean.

ОЦЕНКА ЛИНИЙ ITMI ЯРОВОЙ МЯГКОЙ ПШЕНИЦЫ НА УСТОЙЧИВОСТЬ К ТВЁРДОЙ ГОЛОВНЕ

The aim of the study is to search for new sources of resistance to stinking smut among the ITMI population lines. The article presents analysis of data on the study of reaction of spring soft wheat, which is resistant to stinking smut, to the introduction of pathogen. The experimental part of the work was carried out in 2016-2018 on an infectious background of a phyto-stage in the conditions of the forest-steppe of the Middle Volga region (Samara ARI-branch of SamRC RAS, Bezenchuk country). 77 lines of ITMI mapping population were used as objects, as well as a population of Tilletia caries pathogen collected from zoned and susceptible varieties. In the experiment, healthy seeds (control) and seeds infected with pathogen were sown. For inoculation of wheat seeds with this pathogen, the A. I. Borggardt-Anpilogov method was used. Cleaning was carried out manually, by cutting plants from the plot in the phase of full ripeness. Accounting for damage to samples of stinking smut was carried out in the phase of milk-wax stage of the grain, carefully viewing and counting all the spikes on the plot. A five-grade scale created by V. I. Krivchenko was used for classing the samples resistance to stinking smut. Weather conditions in the years of research were different, but developed mainly favorable for creating an infectious background, as well as for the growth of spring wheat plants. 4 lines had immunity (ITMI-40, 75, 90, 91). Practical stability was observed on 5 lines (damage from 4.3 to 10.0%). 8 lines were poorly susceptible (the maximum lesion was 21.0%). With an average susceptibility, 21 lines were isolated, the remaining lines were mostly affected by more than 50%. Selected samples can serve as a valuable source material for use in immunological breeding programs.

The use of Tn5-mutants Bradyrhyzobium japonicum for regulation of prooxidant-antioxidant processes in soybean plants under drought condition

Aim. To investigate the use of soybean seed inoculation by nodule bacteria obtained by transposon mutagenesis to ensure the effective formation and functioning of symbiotic systems by regulating prooxidant - antioxidant processes and reducing the negative effects of drought on crop productivity. Methods. Microbiological, physiological, biochemical methods, gas chromatography and spectrophotometry. Results. It has been proved that due to the activation of protective antioxidant enzymes of catalase, ascorbate and guaiacol peroxidase in soybean roots and root nodules, adaptive rearrangements of plant metabolism occur aimed at stabilizing the content of prooxidants, hydrogen peroxide, in drought conditions. At the same time, the specific nitrogen-fixation activity of soybean root nodules undergoes no significant changes and indicates the preservation of the effective functioning of the symbiotic apparatus, is the result of activation of protective antioxidant processes and adaptation of the soybean symbiotic system with the participation of Tn-5 mutant Bradyrhizobium japonicum B1-20 to dehydration conditions. Conclusions. The use of inoculation of soybean seeds with the Tn-5 mutant Bradyrhizobium japonicum B1-20 leads to regulation of prooxidant - antioxidant protective processes in plants, helps to increase their nitrogen-fixation potential and maintain grain yield under prolonged exposure to drought. Keywords: soybean (Glycine max (L.) Merr.), hydrogen peroxide, catalase, ascorbate peroxidase, guaiacol peroxidase, drought.