1, 2, 4-triazole derivatives, including tebuconazole, have been reported to show positive physiological effects in cereals apart from fungicidal activity and to increase plants’ tolerance against temperature stress. This study investigates the mechanisms of increasing frost resistance of etiolated winter wheat (Triticum aestivum L., “Irkutskaya” variety) seedlings by tebuconazole-based seed dresser “Bunker” (1.5 μL g−1 of seeds) and tebuconazole (30 μg g−1 of seeds). To identify ABA-dependent and ABA-independent pathways of frost resistance, we used fluridone (FLD, 5 mg L−1), an inhibitor of endogenous abscisic acid (ABA) synthesis. FLD effectively inhibited the accumulation of carotenoids in the shoots and prevented the formation of carotenoids caused by the “Bunker” and tebuconazole. In non-hardened seedlings, FLD stimulated coleoptile and first leaf growth, but did not suppress the growth inhibitory effects of “Bunker” and tebuconazole. In shoots of hardened seedlings, FLD reduced the retarding effect of tebuconazole. Regardless of seedling age, temperature, and the protectant treatment, FLD had no effect on the sugar content in the shoots. FLD did not essentially influence frost resistance induced by “Bunker” and tebuconazole in cold-hardened seedlings. Fluridone increased H2O2 content and guaiacol peroxidase activity under control conditions (both with tebuconazole and without tebuconazole) and during cold hardening (in seedlings from seeds treated with tebuconazole). ABA levels in cold-hardened seedlings treated with FLD alone, tebuconazole alone, or a combination of the two were two to three times lower than in untreated hardened seedlings. Changes in indole-3-acetic and salicylic acids in response to FLD and tebuconazole treatment indicate complex interactions with signaling cellular systems. Our results suggest that tebuconazole activates ABA-independent pathways more strongly than ABA-dependent pathways in enhancing frost resistance. The potential mechanisms of tebuconazole action in plant cells are discussed.

Approximately 220 million hectares of former croplands are abandoned worldwide, with a quarter of this area located in Russia. In these areas, natural zonal vegetation is developing, and the soils, including soil carbon (C) stocks, are recovering. Accumulated organic C serves as a structural and energetic source for soil microorganisms. Postagricultural soil restoration affects organic matter stability, microbial organic carbon decomposition, and C cycling. We studied a chronosequence of abandoned croplands in the Eastern Siberian forest steppe zone (Haplic Luvisol) to assess the effects of cropland natural restoration on the stability of soil organic matter (SOM) and energy stocks. The energy content and thermal stability of C in the bulk soil, in free and occluded particulate organic matter (fPOM and oPOM), and in mineral-associated organic matter (MAOM) were analysed by thermogravimetry and differential scanning calorimetry as proxies for C available for microbial decomposition. The soils sequestered 0.85 Mg C ha(-1) y(-1) (0-30 cm) during the first 25 years after abandonment. In abandoned soils, thermally labile C with an activation energy of 69+0.6 kJ.mol(-1) accumulated 2.8 times faster than did stable C with a higher energy barrier to combustion (80+0.5 kJ.mol(-1)). This increased energy availability and microbial activity led to faster C and nutrient cycling in the abandoned soils than in soils of current croplands. MAOM stored 1.7 times more energy per unit of C (42 kJ.g(-1) C) than did the free and occluded POM fractions (25 kJ.g(-1) C). fPOM was the dominant energy pool for labile C in the restored soil and increased microbial activity. Due to the preferential accumulation of C with lower thermal stability and with greater susceptibility to microbial decomposition in the restored soils, greater CO2 release could occur if these lands are tilled again. The content of thermally stable C also increased in abandoned soils; therefore, we must account for the ecological balance between C sequestration and release after the natural restoration of croplands.

Strobilurin and triazole class fungicides are actively used in agriculture as part of dressers to protect plants from fungal disease. In addition, they have various physiological effects on plants, including increased resistance to adverse environmental factors. The combined effect of these fungicides under water stress is understudied. The present work aims to examine the individual and combined effects of tebuconazole and azoxystrobin on the growth characteristics of wheat and its resistance to water stress. The study used winter wheat (Triticum aestivum L. ) plants grown from seeds treated with tebuconazole (2 mg/50 g seeds) and azoxystrobin (4 mg/50 g seeds) suspensions separately or together. In order to create water stress, five-day seedlings were transferred to 20% polyethylene glycol solution (PEG 6000), with stability assessed at seven and nine days. Tebuconazole was found to have a retardant effect on shoots and stimulate root growth. Azoxystrobin inhibited shoot growth and particularly root growth. When used together, tebuconazole partially reduced azoxystrobin-induced root inhibition. Azoxystrobin increased the negative effect of water stress, while tebuconazole effectively protected the root system of seedlings, partially reducing the effect of azoxystrobin. The stimulation of root growth with tebuconazolewas concluded to play an important role in providing resistance of winter wheat to water stress and to have the potential for use in agriculture.

The formation of the seasonal CO 2 flux depending on the species of cabbage crops used for short-term summer green manuring of the fallow field in the Baikal forest-steppe zone was studied. In field experiments on gray forest soil during the warm season, CO 2 emission rates per day were measured in options with white mustard ( Sinapis alba L.) and oil radish ( Raphanus sativus var. oleifera Metzg). The black follow served as the control. The total CO 2 flux from the soil was calculated by identifying different periods in the fallow treatment technology (before sowing green manure crops, vegetation, and the period after biomass plowing). An increase in the intensity of CO 2 release from the soil after the plowing of green mass was revealed. The enhancement of mineralization processes due to the newly received organic matter of mustard biomass was 27-100%, and radish - 48-142% in relation to the black fallow. The CO 2 emission data corresponded with the yield and quality indicators of the studied cabbage crops. It has been established that from the position of regulation of carbon dioxide fluxes, the use of white mustard for short-term green manure in the conditions of the region is more expedient than oil radish.

Winter rye has a high adaptive capacity to abiotic and biotic stressors compared to other winter crops (wheat, triticale, barley, and oats). High resistance of winter rye to adverse environmental factors and a wide range of its uses increase interest in this crop. The purpose of this research was to evaluate the adaptive capacity of population and hybrid varieties of winter rye and to identify varieties suitable for the soil and climate conditions of Eastern Siberia. A number of winter rye varieties of various geographical origins were tested during three field seasons. In all the field seasons, the population varieties (Tagna, Mininskaya, and Chulpan) were the most productive and most resistant to adverse environmental factors compared to the hybrid wheat (KWS Aviator, KWS Prommo, and KWS Ravo). Statistically significant (p < 0.001 in 2019/2020 and p < 0.001 in 2021/2022) differences in field survival and yield between the population and hybrid varieties were noted.

In order to manage field crop production, reduce the negative impact of abiotic factors, and increase productivity and product quality, the modern agricultural industry uses chemical compounds analogous to endogenous phytohormones. Some of these substances are physiologically valuable due to their capability to improve the resistance of plants to adverse environmental factors. The increased interest in such preparations can be attributed to their low cost and effectiveness at low concentrations. The effect of a protatrane mixture (a, b, c) on changes in the physiological parameters (growth characteristics; water status) of spring wheat (Triticum aestivum L.) was studied at low concentrations (10−6 and 10−9 g/L) under chloride salinity conditions. The plants were grown under laboratory conditions in a CLF PlantClimatics chamber, in which untreated and chemically treated spring wheat seeds were evaluated for changes in morphological and physiological parameters under salt stress conditions (150 mM NaCl). The analysis of obtained data revealed that protatranes have a positive effect on the morphometric parameters and water status of plants under chloride salinity conditions. Thus, the examined substances decrease the inhibition of growth processes under chloride salinity conditions. The treatment of seeds with the studied substances increases the tissue water content while decreasing the osmotic potential drop in leaves and roots. Irrespective of the mix ratio, protatranes help to improve the plant water status and mitigate the negative effects of chloride salinity on plant growth.

Обоснование. Одной из наиболее ценных в хозяйственном отношении сельскохозяйственных культур является соя (Glycine max (L.) Merr.). Интерес к этой культуре у аграриев связан с тем, что соя широко используется как продовольственная, кормовая и техническая культура. Соя является короткодневным растением, чувствительным к интенсивности освещения и продолжительности дня. В связи с этим сорта сои занимают ограниченный ареал возделывания и имеют высокую продуктивность в узком диапазоне агроклиматических условий. Поскольку для условий Иркутской области на сегодняшний день нет рекомендованных сортов сои к возделыванию, представляется важным разработать маркеры скороспелых сортов и сортообразцов сои, способных давать стабильный урожай в условиях длинного светового режима и сниженной суммы активных температур. Цель. Целью данной работы был сравнительный анализ уровней экспрессии генов – потенциальных молекулярных маркеров скороспелости сои в различающихся по скороспелости сортах и сортообразцах сои. В исследование были взяты представляющие на наш взгляд наиболее перспективные с этой точки зрения гены на основе полученных нами ранее данных, а также на основе литературных данных. Материалы и методы. Растения сои сортообразцов №15, 3169/14 и сортов Алтом и Вилана для экспериментов выращивались в контролируемых условиях станции искусственного климата «Фитотрон» на базе СИФИБР СО РАН. Растения выращивались индивидуально в вегетационных сосудах при температурном режиме: день/ночь – 22/16°С; фотопериод – день/ночь - 16,5/7,5 часов; освещенность – 500 µmol*m-2*s-1; влажность – 60%. Для выделения РНК отбирали не развитые до конца вторые тройчатые листья растений сои. РНК с помощью реактивов из набора GeneJET Plant RNA Purification Mini Kit (ThermoScientific, Литва), согласно инструкции производителя. Синтез первой цепи кДНК осуществляли с использованием набора реак-тивов ThermoScientific (Литва), согласно рекомендациям фирмы производителя. ПЦР-РВ проводили на приборе CFX96™ Real-Time PCR Detection System (Bio-Rad, США), используя набор реактивов qPCR mix-HS SYBR (Евроген, Россия), согласно инструкции производителя. Анализ данных ПЦР-РВ проводили с помощью программного обеспечения SFX Manager (Bio-Rad, Германия). Все эксперименты проводились в двух аналитических и трех биологических повторностях. В качестве референсного гена использовали ген, кодирующий актин – Act11. Результаты. С помощью метода ПЦР в реальном времени показано, что из числа исследованных нами генов повышенные уровни экспрессии в скороспелых сортообразцах сои по сравнению с таковыми на стадии V2 – начала развития второго тройчатого листа сои – в позднеспелых сортах наблюдаются преимущественно для генов, кодирующих транскрипционные факторы, преимущественно, содержащие MADS-box. Из этой группы генов в качестве потенциальных маркеров скороспелости сои наиболее перспективными представляются гены, кодирующие ортологи SEP3 арабидопсиса. Отдельно стоит отметить наблюдаемую в нашей работе повышенную в тысячи раз экспрессию гена с неизвестной функцией – ортолога MEE18 арабидопсиса в более скороспелых генотипах сои. Такая гиперэкспрессия этого гена должна определять фенотипические различия между сортами и сортообразцами сои, возможно, и скороспелость растений. Помимо показанной более высокой экспрессии в скороспелых сортообразцах сои хорошо известных регуляторных генов, вовлеченных в реализацию перехода растений от вегетативной к генеративной фазе развития, отдельный интерес представляет выявленная нами повышенное содержание транскрипта гена, возможное участие которого в созревании растений сои пока не показано – гена секойсоларицирезинол дегидрогеназы. Все вышеперечисленные гены являются потенциальными кандидатами в молекулярные маркеры селекции скороспелых сортов и сортообразцов сои, выращиваемых в условиях длинного светового дня Иркутской области. Заключение. Таким образом, в результате проведенных исследований выявлены гены сои, экспрессия которых достоверно повышена в более скороспелых сортах и сортообразцах сои на стадии V2 развития растений, предшествующей стадии бутонизации, Очевидно, что те гены, функция которых по литературным данным связана с регуляцией процессов цветения, являются перспективными молекулярными маркерами скороспелости растений сои.

This study aimed to assess the prospects for the use of azoxystrobin, a fungicide of the strobilurin class, for increasing the resistance of winter wheat to low temperatures. The effect of azoxystrobin on growth processes, cell viability and the content of water-soluble carbohydrates in winter wheat (Triticum aestivum L.), the Ikutskaya variety, was studied. In comparison with other synthetic strobilurins, azoxystrobin is more frequently used in multicomponent fungicidal preparations. Azoxystrobin is a broad- spectrum fungicide that inhibits complex III of the mitochondrial electron transport chain. Experiments were carried out in laboratory conditions using 3-day-old etiolated winter wheat sprouts. The sprouts were grown in a dark place at a temperature of +24 degrees. on azoxystrobin solutions dissolved in a 0.36% aqueous solution of dimethyl sulfoxide, distilled water and a 0.36% dimethyl sulfoxide solution. The effect of various azoxystrobin concentrations (2.5, 5, 10 and 20 mu M) on the growth of sprouts and roots was assessed, along with the viability of sprout and root cells. Azoxystrobin had a concentration-dependent growth-inhibiting effect on sprouts and roots. At concentrations of 2.5 mu M and 20 mu M, the inhibition degree for sprouts varied from 2.8% to 41.7%, respectively. For roots, these values comprised 34.6 and 63.1%, respectively. The growth-inhibiting effect was not accompanied by a decrease in the cell viability of sprouts and roots, which was assessed using in vivo staining with fluorescein diacetate (FDA). The effect of azoxystrobin at a concentration of 10 mu M on the sugar content in germinated sprouts was also evaluated. At this concentration of azoxystrobin, the sugar content was higher by 3.6% in sprouts germinated on a dimethyl sulfoxide solution. Since growth inhibition and sugar accumulation are important factors in plant adaptation to low temperatures, further research into effects of azoxystrobin on the physiological and biochemical parameters of plants associated with the development of low-temperature resistance seems justified.

The integrated protection of plants from diseases, pests and weeds is an essential element of technologies for their cultivation. Contemporary crop research involves the widespread use of fungicides, which is important not only for increasing plant productivity, but also in order to obtain a high-quality crop. Under conditions of significant spread, diseases such as wheat fusarium head blight, loose smut of wheat and rye, rye spur and others not only reduce the productivity of crops, but also prevent the use of grain crops for human nutrition or animal feed purposes. In addition to plant protection, measures aimed at managing crops are of great importance in cultivation technology. This is ensured by various technological methods, including the use of a variety of chemicals, including stimulants and regulators of plant growth and development. In addition to their main target effect, many pesticides are known to cause additional effects on plants. This is expressed not only in varying degrees of phytotoxic manifestations, but also in stimulating and growth-regulating effects. Knowledge of the direction of these effects will allow for more competent application of chemical plant protection products, as well as for obtaining positive and avoiding negative effects. Many contemporary large companies working in the field of plant protection inform agrarians about possible additional effects of the preparation. In addition to practical application, studying the influence of the physiological effects of preparations helps agriculturalists to understand the formation mechanisms of plant resistance to stress. The review discusses the physiological and biochemical effects of triazole fungicidal preparations on plants. Their retardant effect, ability to increase the content of photosynthetic pigments and sugars, effects on respiration, changes in the composition of fatty acids, increased resistance of plants to temperature stresses, water deficiency, as well as chloride salinity and oxidative stress are also clarified. The review also includes the results of our own research on the effects of tebuconazole and tebuconazole-containing protectants on the mechanisms of cold and frost resistance of cereals.

BACKGROUND AND OBJECTIVE:The spring growth of winter cereals depends on the viability of the crowns as it is the key organ of the spring renewal of leaves, stems and roots. After the plants out of wintering, the impact of stressful conditions in the spring period negatively affects the viability of the crowns of winter cereals. The study was aimed at studying the physiological and biochemical reactions of the crowns of winter triticale, depending on the moisture level of the soil after wintering.MATERIALS AND METHODS:The physiological and biochemical reaction of crowns of winter triticale to the change of the soil moisture-30, 60, 90 of the field capacity (FC) was studied under the controlled conditions of the vegetation experience. The viability of crowns winter triticale, water content, free proline, water-soluble carbohydrates and the qualitative composition of dehydrins were investigated.RESULTS:Plant survival and steady water content during the first 10 days is associated with an increase in the concentration of free proline, high content of water-soluble carbohydrates and dehydrins in crowns, regardless of the soil moisture level. At later stages of spring growth resumption (20 and 30 days), a decrease in carbohydrates, dehydrins and proline was noted in the crowns of winter triticale at all the studied levels of soil moisture. These substances are likely playing an important role in the osmotic regulation and protection of the components of the cells of crowns at the initial stage (10 days) of the plants growth resumption.CONCLUSION:The higher content of proline and the low water content of the tissues of crowns were noted in plants in the variant with a lack of moisture. Water deficiency in the period of growth resumption after wintering has a negative effect on the survival of plants.