Winter Wheat Grain Yield Research Articles

Effects of a novel plant growth regulator B2 on stalk quality and grain yield of winter wheat in North China

Effects of a novel plant growth regulator B2 on stalk quality and grain yield of winter wheat in North China

Вплив інгібітора нітрифікації 3,4-диметилпіразолфосфату на продуктивність пшениці озимої за поєднаного використання з КАС-32

Goal. To establish the expediency and effect of using the nitrification inhibitor 3,4-dimethyl pyrazole phosphate (DMPF) in combination with urea-ammonia mixture (KAS-32) on the yield of winter wheat grain. To determine the difference in the yield of winter wheat using different norms of KAS-32 with and without the addition of DMPF. Methods. Field (stationary experiment); laboratory (agrochemical analysis of soil and plant samples); analytical (systematic analysis of long-term results of field experiments and meteorological observations using mathematical and statistical methods, correlation and regression analysis, mathematical modeling, and empirical generalization of established patterns). Results. It was confirmed that the use of DMPF together with KAS-32 significantly influenced the yield of winter wheat. At the same rate of KAS-32, 300 kg/ha in the variant with the use of DMPF, the yield increased by 4.5 t/ha, or 12% compared to the option where KAS-32 was used at the same rate, 300 kg/ha without the use of DMPF. In the variant with a reduced rate of KAS-32, 250 kg/ha with the use of DMPF compared to the option with an increased rate of KAS-32, 300 kg/ha, but without the use of DMPF, the yield increased by 4.2 c/ha or 11.2% over 4 years of research (2018–2021). Conclusions. It was established that in the variants using DMPF together with KAS-32, the productivity increased compared to the control (without fertilizers) by 25.3–25.6 t/ha (67.6–68.4%). In the variants using DMPF together with KAS-32 compared to the variant using KAS-32, but without the use of DMPF, the yield increased by 4.2–4.5 t/ha (11.2–12.0%) over 4 years of research (2018–2021)).

Genomic prediction for grain yield and micro-environmental sensitivity in winter wheat.

Individuals within a common environment experience variations due to unique and non-identifiable micro-environmental factors. Genetic sensitivity to micro-environmental variation (i.e. micro-environmental sensitivity) can be identified in residuals, and genotypes with lower micro-environmental sensitivity can show greater resilience towards environmental perturbations. Micro-environmental sensitivity has been studied in animals; however, research on this topic is limited in plants and lacking in wheat. In this article, we aimed to (i) quantify the influence of genetic variation on residual dispersion and the genetic correlation between genetic effects on (expressed) phenotypes and residual dispersion for wheat grain yield using a double hierarchical generalized linear model (DHGLM); and (ii) evaluate the predictive performance of the proposed DHGLM for prediction of additive genetic effects on (expressed) phenotypes and its residual dispersion. Analyses were based on 2,456 advanced breeding lines tested in replicated trials within and across different environments in Denmark and genotyped with a 15K SNP-Illumina-BeadChip. We found that micro-environmental sensitivity for grain yield is heritable, and there is potential for its reduction. The genetic correlation between additive effects on (expressed) phenotypes and dispersion was investigated, and we observed an intermediate correlation. From these results, we concluded that breeding for reduced micro-environmental sensitivity is possible and can be included within breeding objectives without compromising selection for increased yield. The predictive ability and variance inflation for predictions of the DHGLM and a linear mixed model allowing heteroscedasticity of residual variance in different environments (LMM-HET) were evaluated using leave-one-line-out cross-validation. The LMM-HET and DHGLM showed good and similar performance for predicting additive effects on (expressed) phenotypes. In addition, the accuracy of predicting genetic effects on residual dispersion was sufficient to allow genetic selection for resilience. Such findings suggests that DHGLM may be a good choice to increase grain yield and reduce its micro-environmental sensitivity.

Crop rotation and tillage impact yield performance of soybean, sorghum, and wheat

AbstractThe benefits of no‐till to crop yield depend on environment and crop sequence; thus, understanding their interactions is a long‐term process. This 44‐year field experiment examined grain yield, yield stability, and adaptability of continuous winter wheat (Triticum aestivum L.) (Ct‐WT), continuous soybean [Glycine max (L.) Merrill] (Ct‐SY), continuous grain sorghum [Sorghum bicolor (L.) Moench] (Ct‐GS), soybean–winter wheat rotation (SY‐WT), and soybean‐grain sorghum rotation (SY‐GS) under three tillage systems (NT, no‐tillage; RT, reduced tillage; CT, conventional tillage) near Ashland Bottoms, KS. The temporal variation across the studied years allowed us to evaluate treatments under low‐ and high‐yielding environments. Crop rotation consistently outyielded continuous cropping, and the advantage was enhanced when integrated with NT. Yield stability decreased under NT continuous cropping in most systems. Wheat was adaptable to low‐ and high‐yielding environments with similar grain yield and yield stability among treatments, except for NT Ct‐WT, which had the lowest yield stability and grain yield (2.5 vs. 3.5 Mg ha−1). Soybean grain yield was greater under rotation than Ct‐SY (2.7 vs. 2.0 Mg ha−1) and under NT than RT and CT (2.6 vs. 2.4 Mg ha−1), with similar yield stability. Soybean grown after wheat was more adaptable to low‐yielding environments and grown after sorghum to high‐yielding environments. Sorghum in NT SY‐GS was adaptable to low‐ and high‐yielding environments and had the greatest yield (6.2 Mg ha−1) and yield stability. This long‐term study demonstrated the advantages of crop rotation combined with NT on grain yield, yield stability, and crop adaptability.

Effects of different shallow and saline groundwater depths on soil salinity, evapotranspiration, grain yield and spike traits of winter wheat

AbstractThe contribution of groundwater to evapotranspiration in crop irrigation scheduling is gaining importance worldwide. A two consecutive year wheat experiment was conducted in drainable lysimeters to evaluate the response of grain yield and quality, spike traits, water use efficiency, evapotranspiration and thousand kernel weight of wheat plants under twelve different shallow and saline groundwater conditions. The treatments included three groundwater depths (GWD) (D1: 30 cm, D2: 55 cm and D3: 80 cm) and four groundwater salinities (GWS) (S1: 0.38, S2: 2, S3: 4 and S4: 8 dSm−1). The results show that the average decrease in grain yield for D2and D1compared to D3was 20.9% and 30.7%, respectively, while the decrease for S2, S3and S4compared to S1was 11.8%, 18.0% and 25.1%. The highest evapotranspiration was found in the D3S1treatment (630.1 and 550.1 mm in 2017–2018 and 2018–2019, respectively), which increased by 48.0% and 30.2% in the first and second seasons, respectively, compared to the D1S4treatment. Thus, a GWD at 80 cm with 0.38 dSm−1GWS was able to meet 72% of the total water requirement of wheat under loam soil conditions. Water use efficiency values ranged from 1.49 to 1.65 kg m−3in the first season and from 1.18 to 1.73 kg m−3in the second season, with the highest water use efficiency values found at 80 cm GWD. Regression analysis showed that GWS had a greater effect on water use efficiency than GWD. On average, thousand kernel and hectolitre weights were highest under D3S1, reaching 49.6 g and 77.8 kg hl−1, respectively. Soil salinity increased steadily with increasing GWS at all GWD conditions, and higher soil salinity values were observed at 30 cm GWD. In addition, controlling a groundwater depth at 80 cm with 8.0 dSm−1GWS did not significantly increase soil salinity, which did not result in high grain yield losses. Finally, it is recommended to control groundwater at a constant depth of 80 cm with 0.38 dSm−1GWS after the tillering period of winter wheat to save more irrigation water, control soil salinity and improve yield and grain quality in the region with shallow‐saline groundwater.

ПРОДУКТИВНОСТЬ И ПОКАЗАТЕЛИ КАЧЕСТВА ЗЕРНА ОЗИМОЙ ПШЕНИЦЫ ПРИ РАЗНЫХ СХЕМАХ ПРИМЕНЕНИЯ МИКРОУДОБРЕНИЙ И СТИМУЛЯТОРОВ РОСТА В УСЛОВИЯХ СРЕДНЕГО ПОВОЛЖЬЯ

The research was carried out to study the effect of water softener, biostimulants, macro- and microfertilizers on the yield and quality characteristics of winter wheat grain. The work was carried out in the Republic of Tatarstan in 2018–2020 on leached chernozems. The experiment was carried out according to the scheme: water softener (factor A) - there is no softener, Pekacid water conditioner; growth stimulants and trace elements (factor B) - without the use of drugs, Nutrivant, Stimax, Carbamide, Stimax + Carbamide, Stimax + Nutrivant, Nutrivant + Carbamide, Stimax + Nutrivant + Carbamide. Foliar treatment of winter wheat crops with the growth stimulator Stimaks together with a fertilizer containing microelements, against the background of mineral fertilizers applied by the calculation method to obtain 5 tons of grain per 1 ha, ensured the formation of high yields. The maximum yield in the experiment (5.72 t/ha) was noted in the variant with the use of a three-component tank mixture Stimax + Nutrivant + Urea using Pekacid. The use of a water softener increased the yield of grain in all variants of the experiment. The increase in the control was 0.06 t/ha, and the maximum (0.13 t/ha) was in the variant with the treatment of crops with a mixture of Stimaks + Nutrivant + Urea. The combined use of microfertilizers and growth stimulants when feeding plants in the tillering phase (by spraying) of winter wheat led to an improvement in grain quality. The largest increase in gluten in the experiment (3.3%) was noted in the variant with the tank mixture Stimaks + Nutrivant + Urea and the use of a water conditioner. The highest (27.8%) gluten content was noted in the favorable year 2018 when using the mentioned three-component tank mixture. The increase, compared with the option without drugs, is 2.2%. The use of each drug separately reduced the yield and quality of grain.

Suitable split nitrogen application increases grain yield and photosynthetic capacity in drip-irrigated winter wheat (Triticum aestivum L.) under different water regimes in the North China Plain.

Chemical fertilizer overuse is a major environmental threat, critically polluting soil and water resources. An optimization of nitrogen (N) fertilizer application in winter wheat (Triticum aestivum L.) in association with various irrigation scheduling is a potential approach in this regard. A 2-year field experiment was carried out to assess the growth, yield and photosynthetic capacity of drip-irrigated winter wheat subjected to various split applications of urea (240kg ha-1, 46% N). The eight treatments were, two irrigation scheduling and six N application modes in which, one slow-release fertilizer (SRF). Irrigation scheduling was based on the difference between actual crop evapotranspiration and precipitation (ETa-P). The two irrigation scheduling were I45 (Irrigation scheduling when ETa-P reaches 45mm) and I30 (Irrigation scheduling when ETa-P reaches 30mm). The six N levels were N0-100 (100% from jointing to booting), N25-75 (25% during sowing and 75% from jointing to booting), N50-50 (50% during sowing and 50% from jointing to booting), N75-25 (75% during sowing and 25% from jointing to booting), N100-0 (100% during sowing), and SRF100 (240kg ha-1, 43% N during sowing). N top-dressing application significantly (P<0.05) influenced wheat growth, aboveground biomass (ABM), grain yield (GY) and its components, photosynthetic and chlorophyll parameters, and plant nutrient content. According to the averages of the two winter wheat-growing seasons, the I45N50-50 and I45SRF100 treatments, respectively had the highest GY (9.83 and 9.5t ha-1), ABM (19.91 and 19.79t ha-1), net photosynthetic rate (35.92 and 34.59 µmol m-2s-1), stomatal conductance (1.387 and 1.223mol m-2s-1), SPAD (69.33 and 64.03), and chlorophyll fluorescence FV/FM (8.901 and 8.922). The present study provided convincing confirmation that N applied equally in splits at basal-top-dressing rates could be a desirable N application mode under drip irrigation system and could economically compete with the costly SRF for winter wheat fertilization. The I45N50-50 treatment offers to farmers an option to sustain wheat production in the NCP.

Grain yield and quality of wheat are improved through post-flowering foliar application of zinc and 6- benzylaminopurine under water deficit condition.

Zinc (Zn) as an essential micronutrient and cytokinin as phytohormone not only regulate plant growth but also play fundamental roles in plant tolerance against drought stress. Understating the function and the role of cytokinin in combined with an essential micronutrient, Zn, could improve the choice of a sustainable strategy for improvement of plant drought stress. The objective of this field research was to determine the effect of post-flowering foliar application of ZnSO4 and 6-benzylaminopurine (6-BAP) on grain yield and quality of winter wheat under water deficit condition. Experiments were conducted under filed condition. Drought was imposed by with holding irrigation at the beginning of flowering till the signs of temporary wilting/leaf rolling appeared, after which all plots were irrigated to field capacity. The foliar treatment consisted of (1) foliar application of water, as control treatment; (2) foliar application of 10 g ha-1 6-BAP; (3) Foliar application of 20 g ha-1 6-BAP; (4) Foliar application of 10 g ha-1 6-BAP plus foliar application of 6 kg ha-1 ZnSO4 solution and (5) foliar application of 10 g ha-1 6-BAP plus foliar application of 6 kg ha-1 ZnSO4 solution 2 days before drought imposition. Data were collected on grain and straw yield, yield attributes, harvest index, flag leaf fresh matter and dry matter weight, TaCKX6-D1 expression, phytic acid content in grains, mycorrhiza colonization rate and succinate dehydrogenase (SD) activity. According to ANOVA, the factor 'Zn' significantly affected leaf relative water content (p < 0.001). Relative water content for plants foliar applied with 6-BAP was not statistically significant. Applying Zn increased yield, straw dry weight, and kernel weight relative to plants sprayed with water alone. Increased grain yield due to foliar application of Zn was associated with decrease in cytokinin oxidase/dehydrogenase (TaCKX) and increase in kernel weight. Results showed that the drought stress significantly decreased 1000-grain weight that was accompanied with over-expression of cytokinin oxidase/dehydrogenase (TaCKX). Foliar application of Zn increased the concentration of Zn in grains. The experimental data on the zinc content of grain indicated no significant difference between the 6-BAP at 10 mg L-1 and control treatment. The phytate to Zn molar ratio was significantly affected by foliar applied Zn, but not significantly by applied 6-BAP. In the present study, SD activity of the hyphae of indigenous arbuscular mycorrhizal fungi (IAMF) associated with plant roots was also assayed. Results disclose that SD activity of IAMF was significantly affected by Zn treatments during grain filling stages. In summary, both foliar applied Zn and 6-BAP had the significant effects on all measured parameters in winter wheat. However, spike number, harvest index and mycorrhizal colonization rate were neither significantly affected by Zn nor 6- BAP. Foliar application of Zn at 0.6% (6 kg ha-1) and higher 6-BAP (20 mg L-1 m-2) promoted wheat growth and performances under imposed drought stress condition. Plant that only foliar sprayed with water showed higher level of TaCKX6-D1 expression as compared to Zn treated plants, indicating these plants were more affected by imposed drought relative to those plants treated with Zn. The results of this study provides evidence that a combination of Zn and 6-BAP could be an effective in improvement of drought tolerance of wheat and prevents grain yield from further reduction in terms of quality and quantity due to drought stress.

Yield of winter wheat after non-traditional predecessors in short-term forage crop rotations

Topicality. Winter wheat is the leading grain and food crop in Ukraine, which is often grown without considering requirements for its predecessors. This crop is widely used in short-term crop rotations, in which there are a number of problems arise in obtaining a high and stable winter wheat yield after non-traditional predecessors. Purpose. To determine the winter wheat yield in specialised fodder short-term crop rotation after the non-traditional predecessors for small farms. Methods. In 2018–2021, field trials were conducted in the Vinnytsia region on leached medium loam chernozems with a humus content of 4.2 %. Winter wheat was sown after three predecessors: fodder beet, pumpkin and potato. Results. The longest period from harvesting potato to sowing winter wheat was 49 days. After harvesting the pumpkin, 16 days remained before sowing winter wheat. The shortest period from harvesting fodder beet to sowing winter wheat was 6 days. The plant density of winter wheat after the potato was by 12.0 % higher than after the pumpkin and by 17.7 % higher than after the fodder beet. During the spring regrowth, the highest plant density of winter wheat was observed after the potato, which was 11.9 % more than after the pumpkin and 18.4 % more than after the fod-der beet. At the end of the growing season, the highest number of productive stems was formed by winter wheat plants after the potato –773 pcs/m2, after fodder beet – by 7.8 % less productive stems, and after the pumpkin – by 42.2 % less than after potato. Conclusions. The highest actual grain yield of winter wheat grown after potato amounted to 7.63 t/ha. After fodder beet, the winter wheat yield was 11.3 % lower than after potato and amounted to 6.77 t/ha. The winter wheat yield after the pumpkin was 40.6 % lower than after potato and 33.1 % lower than after fodder beet. Key words: winter wheat, yield, predecessors, fodder beets, pumpkins, potatoes

Effect of late nitrogen nutrition on formation of harvest elements, grain yield, and quality indicators of winter wheat

It is known that almost 50% of winter wheat harvest is due to mineral fertilizers. Among mineral fertilizers, nitrogenous fertilizers are of special importance. The plant’s response to nitrogen fertilizers starts from the initial stages of plant development and continues until the ripening stage. Nitrogen is involved in all physiological processes in the plant. Nitrogen fertilizers differ from other types of macro fertilizers in their mobility. These fertilizers have a quick effect on the plant and are easily absorbed by the plant. There are different opinions about winter wheat fertilization. Some experts believe that the annual rate of nitrogen fertilizers should be applied in the early stages of development, in early spring. Other authors state that nitrogen fertilization is necessary two or three times during the season. In the experiment, a relatively low indicator of grain yield was observed in the control option of 35 q/ha, and the highest indicator was 72 q/ha in the triple-fed option. In the experiment, additional nitrogen fertilization provided an additional grain yield of 21-37 q/ha of winter wheat. The highest results for all quality indicators of grain were recorded in conditions where nitrogen fertilizer was applied at the rate of 80+80+40 kg/ha three times during the growing season. In this variant, the grain transparency was 90%, the protein content was 14.3%, and the gluten content was 30.3%.

ОТЗЫВЧИВОСТЬ ОЗИМОЙ ПШЕНИЦЫ НА ПОДКОРМКИ КОМПЛЕКСНЫМ КОНЦЕНТРИРОВАННЫМ УДОБРЕНИЕМ В УСЛОВИЯХ ПРЕДКАМЬЯ РЕСПУБЛИКИ ТАТАРСТАН

This article presents the results of studying the effect of foliar fertilizing with concentrated complex liquid fertilizer Ultramag Combi in the phase of tillering and earing of winter wheat with doses of 1 l/ha and 2 l/ha, in 2021-2022. The studies were carried out with winter soft wheat of the Scepter variety on the basis of Agrobiotechnopark LLC at the Kazan State Agrarian University on gray forest soils with a humus content of more than 3.0%, mobile phosphorus of more than 250 mg/kg according to Kirsanov, exchangeable potassium of 121-170 mg/ kg, the reaction of the soil medium close to a neutral pH of 6.6. Accounting for the density of seedlings, the structure of plant yield was carried out by the method of sites. Accounting for the actual yield of winter wheat grain was carried out for all variants by a continuous method, followed by conversion to standard (14%) humidity and 100% purity [GOST 13586.5-2015; GOST 30483-97], determination of the quantity and quality of gluten in wheat grain – according to GOST R 54478-2011. The use of complex concentrated fertilizer Ultramag Combi with foliar top dressing in the tillering phase of winter wheat with doses of 1 and 2 l / ha increased the growth of dry biomass, productive bushiness, the safety of seedlings for harvesting, the mass of 1000 grains and the mass of grain from 1 ear, which eventually increased the biological yield compared with the control. Foliar top dressing with Ultramag Combi preparation in the phase of tillering and earing of winter wheat with a dose of 1 l / ha on average over the years of research increased grain yield by 9.5%, and when using a dose of 2 l/ha in the same phases of winter wheat development, the yield increase reached 16.8%.

Coated diammonium phosphate combined with Paecilomyces variotii extracts improves root architecture, enhances spring low temperature tolerance, and increases wheat yield

The growth, development, and grain yield of winter wheat (Triticum aestivum L.) was seriously limited by the low use efficiency of phosphorus (P) fertilizers and the spring low-temperature events. Diammonium phosphate is one of the most important sources of P fertilizers worldwide. Controlled release diammonium phosphate (CRDAP) synchronizes fertilizers P release and crop growth demand is positive to improve P use efficiency (PUE) and reduce P loss, whereas biostimulants such as Paecilomyces variotii extracts (ZNC) have ultrahigh activity in promoting crop growth and abiotic stress resistance. However, little information is available on synergistic effects of CRDAP and ZNC on winter wheat growth. A three-year field experiment from October 2017 to June 2020 was conducted with five treatments: DAP (application of conventional diammonium phosphate); CDAP (CRDAP application); DAPZ (application of diammonium phosphate–ZNC composite); CDAPZ (application of CRDAP–ZNC composite); Control (no P fertilizer or ZNC). Plant growth (root, shoot, and photosynthesis), hormone (auxin content from roots and leaves, and ABA content from leaves), ROS scavenging system (H2O2, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and glutathione reductase (GR)), and soil available P were measured along with yield and PUE. The results showed that the yield and PUE of CDAPZ were significantly more (by 6.0% and 9.3 percentage points, respectively) than for CDAP. The interactive effects between CRDAP and ZNC were evidenced by the CDAPZ enhanced soil available-P supply and increased average available-P content (22.0% more than CDAP in the 0–40 cm soil layer) and improved root growth with 29.9% increase in total root length by CDAPZ than CDAP at the jointing stage. Moreover, the IAA content of roots from CDAPZ was higher than any other treatments, and the effect of ZNC on IAA content was verified by a laboratory incubation experiment. Similarly, the highest photosynthetic rate was found in CDAPZ, which was 11.0–17.0% higher than that in CDAP. The application of CRDAP combined with ZNC decreased H2O2 content by 8.6%, and increased the activities of SOD, POD, CAT, and GR, thereby enhancing the cold tolerance of wheat. Hence, CRDAP–ZNC composite may serve as an emerging green fertilizer technology and play a crucial role in improving crops response to climate change, and increasing crop yield and PUE.

Impact of no-till technology on the fertility of degraded and low-humus soils

The transition to innovative tillage technologies is currently an effective way to preserve and increase the fertility of agricultural land. The purpose of the work is to study the impact of no-till technology on the fertility of degraded and low-humus soils in the Middle Volga region. The main research method was the monitoring of agricultural lands, where traditional (control), minimum and no-till technologies for cultivating grain crops were used as part of field crop rotations. As a result of research conducted over fifteen years on degraded leached chernozems, light gray forest and low-humus soddy-podzolic soil types, it was found that the introduction of no-till technology contributes to an increase in the number of earthworms by 36% and soil invertebrates by 42%. At the same time, the ratio of different groups of soil mesofauna also changes. In particular, an increase in the number of organized predators (ground beetles, rove beetles, spiders, geofields) capable of regulating the number of harmful species of soil animals (for example, wireworm larvae) was revealed. No-till technology has a beneficial effect on agrophysical, agrochemical indicators of fertility and biological activity of degraded and low-humus soils. The crushing of straw and its use as mulch for fifteen years made it possible to form a positive balance of organic matter and increase the content of mobile phosphorus and exchangeable potassium in the soil by an average of 20% and 15%, respectively. Improving the nutritional regime of the soil contributes to a positive impact on the quality characteristics and grain yield of winter and spring wheat, winter rye, barley and corn. With the introduction of no-till technology as the main method of crop production, grain yield increases by 3 and 6% compared to the minimum and traditional technology.

Influence of Different Intensities of Tillage on Physiological Characteristics and Productivity of Crop-Rotation Plants.

The aim of this study was to evaluate the effect of different intensities of tillage on the physiological characteristics and productivity of plants in crop rotation. Five tillage practices (DP-deep ploughing (22-24 cm); SP-shallow ploughing (16-18 cm); SH-shallow harrowing (8-10 cm); DH-deep harrowing (14-16 cm); and DD-direct drilling) were investigated in a long-term experiment in Dotnuva. The crop rotation was as follows: winter oilseed rape → spring wheat → spring barley → field pea → winter wheat. The simplification of conventional tillage negatively affected the photosynthetic indices of the majority of the crop rotation plants. The most favorable conditions for the photosynthetic processes in the plants were identified in the deep-ploughing treatment. The photochemical activity was negatively influenced and leaf senescence was accelerated under direct drilling. Direct drilling significantly decreased the grain yield of winter oilseed rape, spring wheat, and spring barley by 10.5%, 12.8%, and 17.2%, respectively, compared to deep ploughing. The grain yield of winter wheat was similar under deep ploughing and direct drilling; conversely, under shallow ploughing, shallow harrowing, and deep harrowing, the yield tended to decrease compared to deep ploughing.

Physiology and Molecular Breeding in Sustaining Wheat Grain Setting and Quality under Spring Cold Stress.

Spring cold stress (SCS) compromises the reproductive growth of wheat, being a major constraint in achieving high grain yield and quality in winter wheat. To sustain wheat productivity in SCS conditions, breeding cultivars conferring cold tolerance is key. In this review, we examine how grain setting and quality traits are affected by SCS, which may occur at the pre-anthesis stage. We have investigated the physiological and molecular mechanisms involved in floret and spikelet SCS tolerance. It includes the protective enzymes scavenging reactive oxygen species (ROS), hormonal adjustment, and carbohydrate metabolism. Lastly, we explored quantitative trait loci (QTLs) that regulate SCS for identifying candidate genes for breeding. The existing cultivars for SCS tolerance were primarily bred on agronomic and morphophysiological traits and lacked in molecular investigations. Therefore, breeding novel wheat cultivars based on QTLs and associated genes underlying the fundamental resistance mechanism is urgently needed to sustain grain setting and quality under SCS.

Influence of Microbial Preparations on Triticum aestivum L. Grain Quality

Gluten, protein and amino acid composition play an important role in grain quality assessment. Areas of interest of our research include essential amino acids, which are not synthesized in the human body. It is a commonly known fact that large doses of mineral fertilizers increase grain crops’ yield and quality. However, fertilization leads to undesirable effects—in particular, environmental pollution. This creates a need to replace mineral fertilizers, at least partially, with alternative methods. One such method is the use of microbial preparations in modern technologies for growing cereals. This research, therefore, aimed to study the effect of presowing seed inoculation with a microbial preparation (based on phosphate-mobilizing bacterium Lelliottia nimipressuralis CCM* 32-3) on T. aestivum grain quality, namely the content of gluten, protein and amino acids. The analysis of three-year field experiments showed that the highest values were obtained when using the microbial preparation against the background of mineral fertilizers at the rate of P30. Presowing seed inoculation contributed to a significant increase in grain productivity (by 31.5% compared to control). The content of protein and gluten in the grain also increased up to 12.5 % and 28.0%, while in the control, these figures were 10.8% and 21.2%, respectively. Moreover, the total content of amino acids in wheat grain in the variant inoculation + fertilizers (P30) was the highest compared to those without inoculation. The following excess was noted: by 52% compared to control (without fertilizers); and by 29%, 17% and 10% in variants with mineral fertilizers at the rate of P30, P60, and P90, respectively. The obtained research results indicate that the combined application of mineral fertilizer Ammophos (at the rate of P30) and microbial preparation based on the phosphate-mobilizing bacterium L. nimipressuralis CCM 32-3 for presowing seed inoculation is an effective technique that improves the yield and quality indicators of winter wheat grain under the conditions of southern regions with insufficient moisture supply.

The role of winter wheat plant height in the formation of grain yield depending on varietal characteristics and weather conditions

Winter wheat is one of the main food crops that ensures the national food security of Ukraine with general production and high-quality grain. The area of winter wheat sowing ranks first in Ukraine, and the production of high-quality grain is of particular relevance. In the technology of its cultivation, the selection of varieties is a decisive factor in increasing yield and improving the quality of grain. The purpose of this study was to determine the influence of weather conditions and variety characteristics during the year on plant height, lodging resistance, and yield of winter wheat. This paper presents data on the results of the research of 20 varieties of soft winter wheat in the conditions of the Research-to-Practice Centre of the Mykolaiv National Agrarian University from 2017 to 2022. During the study, generally accepted methods were used: system approach, system analysis, analysis and synthesis, field and statistical method. The study also analysed the influence of variety characteristics and weather conditions in the years under study on the yield of soft winter wheat. It was established that the optimal plant height of winter wheat varieties ranged within 94.9-100.7 cm, at which the highest grain yield is formed, from 7.09 t/ha in the Staleva variety to 7.73 t/ha in the Duma Odeska variety. An increase in the height of the winter wheat varieties under study by 4.0-6.4% led to a decrease in yield from 4.5 to 20.9%. It was established that the awned varieties of soft winter wheat formed a higher grain yield, compared to the thornless forms, which had a higher plant height and less lodging resistance. The conducted studies confirmed that, on average, the resistance to lodging was higher in the thornless forms of winter wheat plants, which is 0.4 points higher than in the awned ones. The higher average grain yield of soft winter wheat was formed by varieties of spiny forms, which is 5.8% more than that of awned varieties. The obtained results will contribute to the wide application of the varieties of soft winter wheat under study for this soil and climate zone, which will further contribute to the increase in yield and gross grain harvests.

Sensitivity Analysis and Determination of the Optimal Level of Water Use Efficiency for Winter Wheat and Barley under Different Irrigation Scenarios Using the AquaCrop Model in Arid and Semiarid Climatic Conditions (Case Study: Dehloran Plain, Iran)

The AquaCrop model is one of the most recent models that can simulate the growth rates and yields of various crops based on water consumption levels. To determine the optimal irrigation level, data measured in two crop years (2018–2019) in different irrigation scenarios (full irrigation or 100% water requirement and 90, 80, 70, 60, and 50% irrigation) were calibrated and validated for arid and semiarid climatic conditions using the AquaCrop model. The model was calibrated to simulate the grain yields of winter wheat and barley using R2, RMSE, d, EF, and NRMSE statistical indicators. The obtained values of these indices were, respectively, 0.97, 3, 0.98, 0.94, and 4 for winter wheat and 0.98, 4, 0.92, 0.89, and 7 for barley. The model efficiency was also validated using crop harvest data in the crop year 2019. For grain yield simulation, the calculated values of R2, RMSE, d, EF, and NRMSE statistical indicators were, respectively, 0.99, 4, 0.97, 0.93, and 4.4 for winter wheat and 0.97, 7, 0.94, 0.91, and 9 for barley. The data of field and modeled samples were analyzed by analysis of variance (ANOVA) using the F-test, and significant results were obtained for both crops in all applied scenarios at the 95% level.

Supplemental irrigation and modified plant density improved photosynthesis, grain yield and water productivity of winter wheat under ridge-furrow mulching

In the semi-arid and semi-humid areas, ridge-furrow planting with film mulch on the ridge (R) has been found to significantly enhance crop yields and water productivity, but the interaction effects of supplemental irrigation and plant density on the growth, photosynthesis, grain yield and water productivity (WP) of winter wheat under ridge-furrow mulching are still poorly understood. A two-season experiment (during October 2020 - June 2021 and October 2021 - June 2022) was undertaken on winter wheat in a semi-humid but drought-prone area in northwest China, with two cultivation patterns (R, with ridge width of 40 cm and furrow width of 60 cm; F: traditional flat planting), two supplemental irrigation amounts (I0: rainfed; I60: 60 mm of supplemental irrigation equally applied at the overwintering and regreening stages) and three plant densities (D1:240 × 104 plants ha−1; D2: 360 × 104 plants ha−1; D3: 480 × 104 plants ha−1; with row spacing of 20 cm). The results showed that cultivation pattern, supplemental irrigation and plant density had significant effects on soil water content, leaf area index (LAI), aboveground biomass, relative chlorophyll content (SPAD value), photosynthesis, chlorophyll fluorescence parameters and grain yield of winter wheat. In addition, the interaction effects of cultivation pattern, supplemental irrigation and plant density on SPAD value, fluorescence parameters, grain yield, evapotranspiration and WP were significant. Compared to F and I0, R and I60 significantly increased LAI (4.8 % and 4.6 %), aboveground biomass (9.3 % and 8.1 %), SPAD value (5.0 % and 6.4 %), net photosynthetic rate (19.8 % and 11.7 %), maximal PSII quantum yield (Fv/Fm) (5.2 % and 2.4 %), energy transformation potential activities of PSII (Fv/Fo) (4.1 % and 1.5 %), effective PSII quantum yield (ΦPSII) (12.2 % and 9.5 %), grain yield (10.4 % and 13.5 %) and WP (11.8 % and 7.7 %), while they reduced the relative energy excess at the PSII level. Increasing plant density generally improved LAI, aboveground biomass, but it reduced SPAD value, net photosynthetic rate and fluorescence parameters. Grain yield and WP reached their maximum values at D2 under R and at D3 under F, which was because R had a higher plant number (by 25 %) in each row at D3 compared to F due to the decreased row number resulting from the existence of 40-cm-wide ridge under R. The greatest grain yield (7383.5 kg ha−1 and 8577.4 kg ha−1) and WP (20.03 kg ha−1 mm−1 and 21.77 kg ha−1 mm−1) were obtained under RI60D2 during the two growing seasons. These results suggest that ridge-furrow mulching combined with supplemental irrigation and modified plant density of 360 × 104 plants ha−1 can produce high grain yield and WP for winter wheat in the semi-humid but drought-prone areas of northwest China.

Realization of the adaptive yield potential of the assortment of winter wheat in the Steppe zone under different growing conditions

Climate changes in recent decades have increased the degree of risks in crop production. The consequence of such processes is an increase in the temperature regime against the background of a significant moisture deficit in critical periods of plant growth and development. Accordingly, research aimed at establishing the adaptability of plants to such climatic changes is relevant and timely. The purpose of the research is to establish the principles of implementing the adaptive potential of new varieties of winter wheat of different types of development in the Steppe zone under the conditions of climate change. Records and their assessment were carried out according to the generally accepted methods of Ukrainian variety testing with mandatory statistical and dispersion analysis of the results of field experiments. The establishment of indicators of the stability of quantitative traits and plasticity was carried out using the Eberhard-Russell algorithm, which is based on a regression analysis of the dependence of the grain yield of winter wheat of different varieties on the environmental index. The results of the research established that universal type varieties with a stem length of 85-90 cm are the most suitable for irrigated and non-irrigated conditions. Regression analysis of the data on the plasticity and stability of the elements of the crop structure in different varieties of winter wheat proved that their variability directly depends on the genotype and ecological gradients. According to the results of the assessment of the adaptive potential, it was established that the parameters of plasticity (bi = 0.804-0.989) and yield (7.33-7.63 t/ha exceed the standard by 10.4-14.9%) showed winter wheat varieties of the universal type - Askaniyska, Askaniyska Bereginya, Perlyna, Znahidka Odeska, while Khersonska 99, Kirena, Yaroslavna, Kuyalnyk, etc. were characterized by an intensive type of development. Varieties of the universal type were more plastic and stable in the formation of ear productivity, compared to short and tall biotypes. The scientific significance of the research lies in the substantiation of scientific principles, practical recommendations for improving varietal agricultural technology of winter wheat, which had different genetic and ecological origins, in irrigated and non-irrigated conditions of the Steppe zone