Optimization of onion production technology under annual growing in Non-Chernozem zone

Сегодня лук-репка занимает в стране третье место по площади возделывания среди овощных культур при средней урожайности в 2019 году 27,8 т/га. Потенциал современных сортов и гибридов составляет 100 – 120 т/га. В условиях Нечерноземья проблема поражения лука пероноспорозом наиболее злободневна. Цель исследований – оптимизация элементов технологии производства лука-репки в однолетней культуре (предпосевная обработка семян смесью ризосферных ассоциативных бактерий, нормы и сроки внесения бактерий совместно с минеральными удобрениями, нормы и сроки внесения фунгицидов), обеспечивающих урожайность 70–80 т/га на аллювиальных луговых почвах Нечерноземной зоны. Полевые опыты были проведены на опытном поле ВНИИО согласно стандартных методик. Почва участка аллювиальная луговая среднесуглинистая. Содержание гумуса в слое 0-20 см составляет 3,0–3,2%, pН солевой вытяжки колеблется в значительных пределах 5,0-6,5. Содержание суммы поглощенных оснований 45,0 мг-экв. на 100 г почвы. Содержание Р2О5 – 22,0 мг на 100 г почвы (по Чирикову), калия – 15,2 мг (по Масловой), общего азота — 6,0 мг. В 2018 – 2020 годах было установлено, что: обработка семян лука смесью микробиологических препаратов ризосферных ассоциативных бактерий Экстрасол (штамм Bacillus subtilis Ч-13), Азотовит (штамм Azotobakter chroococcum) и Фосфатовит (штамм Bacillus mucilaginosus) дозами, согласно рекомендаций производителей, не показала достоверного увеличения полевой всхожести испытанных вариантов по отношению к контролю. Внесение смеси ризосферных ассоциативных бактерий препаратов БисолбиСан (штамм Bacillus subtilis Ч-13), Азотовит (штамм Azotobakter chroococcum) и Фосфатовит (штамм Bacillus mucilaginosus) суммарными дозами, л/га: 20,0; 60,0; 70,0;80,0; 90,0; совместно с минеральными подкормками на луке в однолетней культуре обеспечивает значительную (до 20%) прибавку урожайности. Сроки и нормы внесения препаратов требуют дальнейшей оптимизации. Имеет место усиление иммунитета растений против пероноспороза при некорневых обработках фунгицидами Ридомил Голд МЦ и Метаксил совместно с бактериальным препаратом БисолбиСан (штамм Bacillus subtilis Ч-13) в 1% концентрации рабочего раствора. Интервалы обработок 7 – 10 дней фунгицидами Ридомил Голд МЦ и Ревус Топ (на луке не зарегистрирован) следует считать оптимальными против пероноспороза. Currently, the onion-turnip occupies the third place in the country in terms of cultivation area among vegetable crops with an average yield of 27.8 t/ha in 2019 year. The potential of modern sorts and hybrids is 100-120 t/ha. In the conditions of Non-Chernozem zone, the problem of onion disease with peronosporosis is the most urgent. The aim of the research is to optimize the elements of the onion – turnip production technology in an annual crop (pre-sowing seeds treatment with a mixture of rhizospheric associative bacteria, norms and terms of application of bacteria together with mineral fertilizers, norms and terms of application of fungicides), providing a yield of 70-80 t/ha on alluvial meadow soils of the Non-Chernozem zone. Field experiments were conducted at the ARRIVG experimental field according to standard methods. The soil of the site is alluvial meadow medium loamy. The humus content in the 0-20 cm layer is 3.0 — 3.2%, pH of the salt extract varies in the significant range of 5.0-6.5. The content of the sum of absorbed bases is 45.0 mg-eq. per 100 g of soil. The content of P2O5 is 22.0 mg per 100 grams of soil (according to Chirikov), potassium –15.2 mg (according to Maslova), total nitrogen-6.0 mg. In 2018 – 20 years it was found that: Treatment of seeds onion mixture of microbiological preparations associative rhizosphere bacteria Extrasol (strain Bacillus subtilisCH-13), Azotovit (strain Azotobakter chroococcum) and Fosfatovit (strain Bacillus mucilaginosus) doses, according to the manufacturer's recommendations, did not show a significant increase in germination tested options with respect to the control; Introduction of a mixture of rhizospheric associative bacteria preparations BisolbiSan (Bacillus subtilis strain CH-13), Azotovit (Azotobakter chroococcum strain) and Fosfatovit (Bacillus mucilaginosus strain) in total doses, l/ha: 20,0; 60,0; 70,0;80,0; 90,0; together with mineral fertilizing on the onion in an annual crop, it provides a significant (up to 20%) increase in yield. The terms and rates of application of drugs require further optimization. There is an increase in the immunity of plants against peronosporosis during non-root treatments with fungicides Ridomil Gold MC and Metaxil together with the bacterial preparation BisolbiSan (Bacillus subtilis strain CH-13) in 1% concentration of the working solution. Treatment intervals of 7-10 days with the fungicides Ridomil Gold MC and Revus Top (not registered on the onion) should be considered optimal against peronosporosis.

Changes in the taxonomic structure of the microbiome of chernozem southern of the rhizosphere Triticum aestivum L. under the influence of associative bacteria strains

The influence of strains associated with Triticum aestivum L. has been established on the taxonomic structure of the rhizosphere of the southern сhernozem of Crimean Steppe. Seventeen dominant families and 126 families with a minor share are defined in the prokaryotic biome.

INFLUENCE OF STRAINS ASSOCIATED WITH TRITICUM AESTIVUM L. ON MICROBIOCENOSIS IN THE RHIZOSPHERE OF WINTER WHEAT OF CHERNOZEM SOUTHERN

Pre-sowing inoculation with strains of associative bacteria is one of the promising methods for increasing the productivity of agricultural crops. These microorganisms are able to stimulate the growth processes of plants, improve their mineral nutrition, increase phytoimmunity and resistance to adverse factors. The aim of the research is to study the influence of strains with a high associative potential to Triticum aestivum L. on the microbiocenosis in the rhizosphere of soft wheat of several varieties grown on chernozem southern. The studies were carried out in 2018–2020 using three varieties – ‘Ermak’, ‘Bagheera’, ‘Lydia’. The experiments were laid on plots (accounting area – 25 m2) in systematic design, replicated four times. The climate of the study area is characterized as arid (steppe). Inoculation was carried out before wheat seeds sowing; option without treatment served as a control. Sampling was carried out in the most active phase – flowering (in May 2019 and 2020). In the course of the research, we found that changes in the number of microorganisms of various ecological-trophic groups of chernozem southern in the rhizosphere of wheat occur under the influence of bacterial strains associative to T. aestivum. Wheat variety ‘Bagheera’ was found to be the most responsive to seed bacterization; the average yield increase over two years of research was in the range of 0.2-0.4 t/ha or 5-10%. Calculation of coefficients and indices indicating the direction of mineralization processes in the soil made it possible to establish that inoculation promotes their activation. The results of the correlation analysis based on two-year data obtained after studying three varieties of winter wheat showed that the number of bacteria of the genus Azotobacter has the greatest influence on the yield – the correlation index is 0.81 at p <0.05.

Prospect of using oilcakes in biotechnology of microbial preparations

The actual problem in the development of new and improvement of existing forms of microbial preparations for crop production is the search for technological and economical components of the substrate to increase the titer of bacteria and keep their viability for a long period. The aim of our research was to study the technological effectiveness of the oilcake obtained after oil extraction from seeds of Linum usitatissimum L. (flax) and Brassica spp. L. (mustard) as a component of a liquid nutrient medium for the cultivation of associative bacteria. The addition of mustard and flax cake to the cultivation medium of P. polymyxa CCM P contributed to an increase in the titer of bacteria by 3.1 and 4.3 times, respectively, compared to control. We found that mustard cake has a stimulating and stabilizing effect on P. polymyxa CCM P, as well as a stabilizing one on L. nimipressuralis 32-3 CCM when storing for a month.

Biological activity of Oryza sativa L. rhizosphere after introduction of associative bacteria strains

The article presents the results of studies of biological activity in the rhizosphere system associative bacteria − Oryza sativa L. The pre-sowing treatment of seeds with associative symbionts activates biological processes in the rhizosphere and contributes to the increased productivity of Oryza sativa L. The number of grains per spike rose by 28.2-59.0%, 1000-grain weight – by 6.2%-10.6% compared to control.