Wheat Shoots Research Articles

Alleviative effect of iron chlorin e6 on isoproturon phytotoxicity to wheat

Abstract Isoproturon phytotoxicity to wheat (Triticum aestivum L.) is a worry for many farmers in chemical control of weeds in wheat fields, especially in subzero weather conditions. Iron chlorin e6 (ICe6), a new plant growth regulator, has been reported to enhance crop stress resistance to alleviate damage caused by stress; however, it is not clear whether ICe6 has an alleviative effect on isoproturon phytotoxicity to wheat. We determined the alleviative effect of ICe6 on isoproturon phytotoxicity to wheat, and 0.018 g ai ha−1 was the optimal dose. Meanwhile, we also studied the photosynthetic pigment content, photosynthetic parameters, oxidative stress indicators, and antioxidant enzyme activity of wheat treated with the three different treatments. We found that the photosynthetic pigment content, antioxidant enzyme activity, and photosynthesis of wheat damaged by isoproturon were significantly lower than those of the control, and the hydrogen peroxide (H2O2) and malondialdehyde (MDA) content increased. These results indicate that isoproturon stress significantly weakened the photosynthetic and antioxidant capacity of wheat. The photosynthetic pigment content, photosynthetic parameters (excluding intercellular CO2 concentration), and antioxidant enzyme activity of isoproturon+ICe6– treated wheat were significantly higher than those of isoproturon-treated wheat. The H2O2 and MDA content was significantly lower than that of isoproturon-treated wheat. These results indicate that ICe6 treatment maintained the photosynthetic pigment content of wheat and relatively improved photosynthetic capacity, allowing photosynthesis to proceed normally. ICe6 treatment also limits the decrease in antioxidant enzyme activity, effectively clearing excess reactive oxygen species and ultimately alleviating membrane lipid peroxidation damage. In summary, ICe6 not only enhances stress resistance and increases yield in crops such as soybean [Glycine max (L.) Merr.] and canola (Brassica napus L.), but also has an alleviating effect on the isoproturon phytotoxicity to wheat, which is manifested by the improvement of photosynthetic and antioxidant abilities, ultimately leading to an increase in wheat shoot height and shoot fresh weight.

Enhanced phosphorus availability and cadmium remediation using phosphate-solubilizing bacteria-loaded biochar in contaminated soils

Phosphate-solubilizing bacteria (PSB) have garnered extensive attention for their ability to improve soil phosphorus (P) availability and their potential applications in bioremediation. However, the efficacy of PSB is contingent upon their colonization in soils, which can be hindered by the toxicity of heavy metals such as cadmium (Cd). Utilizing biochar as a protective carrier for PSB presents a promising strategy to address this challenge. This study investigated the effects of PSB-loaded biochar on soil P pools and wheat (Triticum aestivum L.) growth under Cd-contaminated conditions. Results indicated that biochar loading facilitated the colonization and functioning of the inoculated PSB strain (Bacillus subtilis), as evidenced by increased soil cultivatable PSB abundance and phosphatase activity as well as increased relative abundance of Bacillus in bacterial community. Consequently, improved soil P availability and reduced soil exchangeable Cd content were observed, leading to a 30.3% increase in wheat shoot biomass, a 50.4% increase in P accumulation, and a 24.1% reduction in Cd accumulation in wheat shoots under the PSB-loaded biochar treatment. Significant shifts in bacterial community composition were revealed by 16S rRNA amplicon sequencing and enhanced microbe-mediated metabolic activities were observed, as demonstrated by soil enzyme assays and metabolome analysis. Overall, these findings underscore the potential of PSB-loaded biochar to enhance P availability, mitigate Cd toxicity, and shape the soil microbial community, offering a promising strategy for sustainable nutrient management and bioremediation in Cd-contaminated agricultural soils.

Cadmium (Cd) detoxification and activation of plant defense enzymes activation in Wheat (Triticum aestivum) through the use of endophytic Bacillus thuringiensis and Salix alba root powder

Cadmium (Cd) is a toxic heavy metal and a threat to the ecosystem therefore the current investigation was designed to use endophytic bacteria from the Salix alba roots and to investigate its plant growth promoting and Cd detoxification ability with and without Salix alba root powder. In a complete randomized design (CRD), the cadmium sulfate was applied at the rate of 20mg/kg and 40mg/kg soil. The Bacillus thuringiensis (Accession # MW979616) was identified from Salix alba roots. The combination of Bacillus thuringiensis inoculated seeds +0.5gm root powder showed significant increase in wheat shoot dry weight, root fresh weight, catalase, and ascorbate peroxidases by 457%, 223%, 105% and 74%, respectively. The application of Bacillus thuringiensis with Salix alba root powder boosted the plant growth and defense at higher concentrations of Cd. In another treatment with Bacillus thuringiensis inoculated seeds + CdSO4 40mg/kg + 0.5gm root powder significantly increased the shoot fresh weight, root fresh weight, root dry weight, proline, sugar, superoxide dismutase, and peroxidase by 456%, 650%, 115%, 91%, 80%, 350%, and 250%, respectively with 80% reduction in plant Cd accumulation and increased bacterial population. Bacillus thuringiensis and Salix alba root powder can be useful for plant growth, Cd toxicity mitigation, accelerating bacterial activity in Cd-contaminated soil and uplifting the plant defense under heavy metal stress.

Unveiling influences of metal-based nanomaterials on wheat growth and physiology: From benefits to detriments

Metal-based nanomaterials (MNs) are widely used in agricultural production. However, our current understanding of the overall effects of MNs on crop health is insufficient. A global meta-analysis of 144 studies involving approximately 2000 paired observations was conducted to explore the impacts of MNs on wheat growth and physiology. Our analysis revealed that the MN type plays a key role in influencing wheat growth. Ag MNs had significant negative effects on wheat growth and physiology, whereas Fe, Ti, and Zn MNs significantly increased wheat biomass and photosynthesis. Our study also observed a clear dose-specific effect, with a decrease in wheat shoot biomass with increasing MN concentrations. Meanwhile, MNs with small sizes (<25 nm) have no significant impacts on wheat growth. Furthermore, both the root and foliar applications significantly improved wheat growth, with no considerable differences. Using a machine learning approach, we found that the MN type was the main driving factor affecting wheat shoot biomass, followed by MN dose and size. Overall, wheat growth and physiology can be negatively influenced by specific MNs, for which a high dose and small size should be avoided in practical applications. Therefore, our study can provide insights into the future design and safe use of MNs in agriculture and increase the public acceptance of nano-agriculture.

Reclaiming selenium from water using aluminum-modified biochar: Adsorption behaviors, mechanisms, and effects on growth of wheat seedlings

Although selenium is an essential nutrient, its contamination in water poses serious risks to human health and ecosystems. In this study, aluminum-modified bamboo biochar (Al-BC) was developed to reclaim Se(VI) from water. Compared to pristine biochar (BC), Al-BC had a larger specific surface area (176 m2/g) and pore volume (0.180 cm³/g). The modification, achieved by loading AlOOH and Al2O3 particles onto the surface, enabled Al-BC to achieve a maximum adsorption capacity of 37.6 mg/g for Se(VI) within 2 h and remove 99.6% of Se(VI) across a pH range of 3–10. The main adsorption mechanism of Se(VI) involved electrostatic attraction, forming outer-sphere complexes between Se(VI) and AlOOH sites on the biochar. The bioavailability of Se sorbed on the spent biochar (Al-BC-Se) was thus evaluated. It was discovered that Al-BC-Se successfully released Se(VI), which impacted the growth of wheat seedlings. The Se content reached 134 μg/g dry weight (DW) in wheat shoots and 638 μg/g DW in roots, significantly exceeding normal selenium content (<40 μg/g DW). By successfully applying the modified biochar to capture selenium from water through adsorption and then reusing it as an essential nutrient in soil, this study suggests the promising feasibility of the "removal-collection-reuse" approach for the circular economy of selenium in wastewater.

Microplastic exposure inhibits nitrate uptake and assimilation in wheat plants

Microplastic (MP) contamination in soil severely impairs plant growth. However, mechanisms underlying the effects of MPs on plant nutrient uptake remain largely unknown. In this study, we revealed that NO3− content was significantly decreased in shoots and roots of wheat plants exposed to high concentrations (50–100 mg L−1) of MPs (1 μm and 0.1 μm; type: polystyrene) in the hydroponic solution. Isotope labeling experiments demonstrated that MP exposure led to a significant inhibition of NO3− uptake in wheat roots. Further analysis indicated that the presence of MPs markedly inhibited root growth and caused oxidative damage to the roots. Additionally, superoxide dismutase and peroxidase activities in wheat roots decreased under all MP treatments, whereas catalase and ascorbate peroxidase activities significantly increased under the 100 mg L−1 MP treatment. The transcription levels of most nitrate transporters (NRTs) in roots were significantly downregulated by MP exposure. Furthermore, exposure to MPs distinctly suppressed the activity of nitrate reductase (NR) and nitrite reductase (NiR), as well as the expression levels of their coding genes in wheat shoots. These findings indicate that a decline in root uptake area and root vitality, as well as in the expression of NRTs, NR, and NiR genes caused by MP exposure may have adverse effects on NO3− uptake and assimilation, consequently impairing normal growth of plants.

Species interactions and bacterial inoculation enhance plant growth and shape rhizosphere bacterial community structure in faba bean – wheat intercropping under water and P limitations

Grain legumes / cereals intercropping systems with microbial inoculants, hold promise for improving crop productivity under stressful conditions. However, the tripartite interaction involving intercropping system, associated microbiota and stress combining water deficit and low phosphorus (P) availability remains understudied. This study evaluated the impact of three bacterial consortia (C4, C6, and Cref containing Rhizobium and PSB strains) including single Rhizobium (Rhizobium laguerreae) on the agro-physiological performance of wheat (Triticum durum) and faba bean (Vicia faba) grown as intercrops or sole-crops under P and water deficient conditions. Inoculation, especially with C6, significantly improved shoot and root biomasses of both wheat (up to 66 and 81 %) and faba bean (up to 54 and 266 %) intercrops compared to single Rhizobium inoculation and control treatments. Intercropping generally outperformed sole-cropping in above-ground physiology, root morphological traits, shoot and root P content, with a notable effect in response to C6 exhibiting low microbial biomass P. Changes in bacterial community structure were primarily driven by cropping pattern and water regime rather than bacterial inoculation. Intercropping maintained bacterial diversity but shifted community structure, favoring Proteobacteria. Overall, inoculating intercropped wheat and faba bean with Rhizobium-containing consortia induced beneficial below-ground interspecies interactions under water and P-limiting conditions.

Combined effect of gallic acid and zinc ferrite nanoparticles on wheat growth and yield under salinity stress

Salinity stress significantly impacts crops, disrupting their water balance and nutrient uptake, reducing growth, yield, and overall plant health. High salinity in soil can adversely affect plants by disrupting their water balance. Excessive salt levels can lead to dehydration, hinder nutrient absorption, and damage plant cells, ultimately impairing growth and reducing crop yields. Gallic acid (GA) and zinc ferrite (ZnFNP) can effectively overcome this problem. GA can promote root growth, boost photosynthesis, and help plants absorb nutrients efficiently. However, their combined application as an amendment against drought still needs scientific justification. Zinc ferrite nanoparticles possess many beneficial properties for soil remediation and medical applications. That’s why the current study used a combination of GA and ZnFNP as amendments to wheat. There were 4 treatments, i.e., 0, 10 µM GA, 15 μM GA, and 20 µM GA, without and with 5 μM ZnFNP applied in 4 replications following a completely randomized design. Results exhibited that 20 µM GA + 5 μM ZnFNP caused significant improvement in wheat shoot length (28.62%), shoot fresh weight (16.52%), shoot dry weight (11.38%), root length (3.64%), root fresh weight (14.72%), and root dry weight (9.71%) in contrast to the control. Significant enrichment in wheat chlorophyll a (19.76%), chlorophyll b (25.16%), total chlorophyll (21.35%), photosynthetic rate (12.72%), transpiration rate (10.09%), and stomatal conductance (15.25%) over the control validate the potential of 20 µM GA + 5 μM ZnFNP. Furthermore, improvement in N, P, and K concentration in grain and shoot verified the effective functioning of 20 µM GA + 5 μM ZnFNP compared to control. In conclusion, 20 µM GA + 5 μM ZnFNP can potentially improve the growth, chlorophyll contents and gas exchange attributes of wheat cultivated in salinity stress. More investigations are suggested to declare 20 µM GA + 5 μM ZnFNP as the best amendment for alleviating salinity stress in different cereal crops.

Effects of biochar types on seed germination, growth, chlorophyll contents, grain yield, sodium, and potassium uptake by wheat (Triticum aestivum L.) under salt stress

Soil salinity is a significant challenge in agriculture, particularly in arid and semi-arid regions such as Pakistan, leading to soil degradation and reduced crop yields. The present study assessed the impact of different salinity levels (0, 25, and 50 mmol NaCl) and biochar treatments (control, wheat-straw biochar, rice-husk biochar, and sawdust biochar applied @ 1% w/w) on the germination and growth performance of wheat. Two experiments: a germination study and a pot experiment (grown up to maturity), were performed. The results showed that NaCl-stress negatively impacted the germination parameters, grain, and straw yield, and agronomic and soil parameters. Biochar treatments restored these parameters compared to control (no biochar), but the effects were inconsistent across NaCl levels. Among the different biochars, wheat-straw biochar performed better than rice-husk and sawdust-derived biochar regarding germination and agronomic parameters. Biochar application notably increased soil pHs and electrical conductivity (ECe). Imposing NaCl stress reduced K concentrations in the wheat shoot and grains with concomitant higher Na concentrations in both parts. Parameters like foliar chlorophyll content (a, b, and total), stomatal and sub-stomatal conductance, and transpiration rate were also positively influenced by biochar addition. The study confirmed that biochar, particularly wheat-straw biochar, effectively mitigated the adverse effects of soil salinity, enhancing both soil quality and wheat growth. The study highlighted that biochar application can minimize the negative effects of salinity stress on wheat. Specifically, the types and dosages of biochar have to be optimized for different salinity levels under field conditions.

Inhibition of Cadmium Accumulation in Wheat Shoots by Propineb Fungicide Application

Inhibition of Cadmium Accumulation in Wheat Shoots by Propineb Fungicide Application

Agronomy biofortification of wheat grain in a saline and calcareous soil

Agronomy biofortification is an important crop management strategy to enhance concentrations of micronutrients in edible portions. The availability of micronutrients for plant uptake is reduced by the high salinity, pH, and lime of soils. Hence, this study aimed to determine the most appropriate time and the best ratio of zinc (Zn) and iron (Fe) consumption during the wheat growth stages in a saline and calcareous soil. The experiment consisted of two factors with four levels; 0, 30, 60, and 120 kg Zn ha−1 as Zn0, Zn1, Zn2, and Zn3 respectively, and 0, 2.5, 5, and 7.5 kg Fe ha−1 as Fe0, Fe1, Fe2, and Fe3 respectively, in a randomized complete block design with four replications. The results showed that the interaction effects of Fe and Zn fertilizers application were significant on the wheat yield indices and concentration of Fe and Zn in wheat shoots and grain. The simultaneous application of 120 kg Zn ha−1 and 5 kg Fe ha−1 caused significant improvement (p < 0.05) in thousand kernel weight (9.1%) and subsequently grain yield (23.4%) compared to the control treatment. The Zn concentration in the wheat shoot during tillering (37.0–58.2 mg Zn kg−1) was higher than the other two growth stages (elongation (29.2–40.8 mg Zn kg−1) and booting (20.0–31.0 mg Zn kg−1)). While the highest Fe concentration in wheat shoots was observed at the stem elongation stage (98.5–268.8 mg Fe kg−1), then the booting stage (91.0–150.8 mg Fe kg−1) and finally the least absorption was at the tillering (80.0–120.0 mg Fe kg−1). Because of the high calcium carbonate, salinity and Zn- deficient soil of the experimental site, the Zn concentration in wheat grain was obtained in a range of 3 to 19 mg kg−1. The results clarified that the fertilizer application of 30 kg Zn ha−1 and 2.5 kg Fe ha−1 can be proportionally and simultaneously increased the concentration of Fe and Zn in wheat grain by 100%. Therefore, the soil application of 30 kg Zn and 2.5 kg Fe per hectare proposed for improvement in quantitative (619 kg ha−1 increase in wheat grain yield) and qualities (100% increase in grain Zn and Fe concentration and 8% increase in thousand kernel weight) indices of wheat yield in calcareous and saline soils.

Reduced tillering and dwarfing genes alter root traits and rhizo-economics in wheat.

The tiller inhibition (tin) and Reduced height (Rht) genes strongly influence the carbon partitioning and architecture of wheat shoots, but their effects on the energy economy of roots have not been examined in detail. We examined multiple root traits in three sets of near-isogenic wheat lines (NILs) that differ in the tin gene or various dwarfing gene alleles (Rht-B1b, Rht-D1b, Rht-B1c and Rht-B1b + Rht-D1b) to determine their effects on root structure, anatomy and carbon allocation. The tin gene resulted in fewer tillers but more costly roots in an extreme tin phenotype with a Banks genetic background due to increases in root-to-shoot ratio, total root length, and whole root respiration. However, this effect depended on the genetic background as tin caused both smaller shoots and roots in a different genetic background. The semi-dwarf gene Rht-B1b caused few changes to the root structure, whereas Rht-D1b, Rht-B1c and the double dwarf (Rht-B1b + Rht-D1b) decreased the root biomass. Rht-B1c reduced the energy cost of roots by increasing specific root length, increasing the volume of cortical aerenchyma and by reducing root length, number, and biomass without affecting the root-to-shoot ratio. This work informs researchers using tin and Rht genes how to modify root system architecture to suit specific environments.

Lignin-rich extracts as slow-release coating for phosphorus fertilizers

Lignin (L) is the most abundant three-dimensional polymer with versatile yet attractive structural features and chemical properties for applicability as a coating. The properties of lignin are mainly related to its botanical origin, structure and extraction method. Although there has been a lot of interest in using lignin in fertilizing systems, only limited attempts have been dedicated to studying the effect of the lignin structure and origin on the release of P fertilizer. Thus, the aim of this work was to study the effect of lignin polymers, extracted from different plant biomass, as coating materials for P fertilizers. Thus, the effect of the structural features originating from the botanical origin on the properties of coated fertilizers and their slow release were established. To this end, three lignocellulosic biomass, namely olive pomace (OP), barley straw (BS) and wood shavings (WS) were used as feedstock to extract lignin polymers. Those chemical compositions and thermochemical properties were characterized prior to their application as coating for triple super phosphate (TSP) fertilizer. Coated fertilizers were characterized for their morphology and coating thickness prior to their evaluation as slow release P-based fertilizer. A distinct slow P release behavior was reported for lignin-coated fertilizers with TSP@L-OP being the slowest as compared to TSP@L-WS, TSP@L-BS as well as pristine TSP, which confirm that the botanical origin and most likely the chemical structures of lignin has significant impact on the properties of the coating materiel. A 100 % release of P from the uncoated TSP was observed after 3 days, while the released amount ranged from only 16.9 % for TSP@L-OP up to 33.4 % for TSP@L-BS. The impact of these coated fertilizers on nutrients uptake and wheat growth was also scrutinized and an noticeable improvement of wheat shoot biomass was observed with the coated TSP treatments reaching up 57.8 % for TSP@BS, 78.1 % for TSP @WS and 93.7 % for TSP @OP, compared to uncoated TSP. This was concomitant to a slight increase of P concentration in shoots, roots and rhizosphere soil, which confirmed the positive effect of slow release P fertilizers on plant growth.

67Zn and 111Cd labelled green manure to determine the fate and dynamics of zinc and cadmium in soil–fertilizer–crop systems

ABSTRACT Isotope source tracing enables to accurately determine the fate of nutrients that are applied with fertilizers to soils. While this approach is well established for major nutrients such as nitrogen, it is not yet established for trace metals. Here, we aimed to determine the fate of the micronutrient zinc (Zn) and the contaminant cadmium (Cd) that were applied with an organic fertilizer to a soil–wheat system. A pot study was conducted in which wheat was grown on an alkaline soil. The soils received green manure and/or soluble Zn fertilizer and were compared with non-fertilized control treatments (n = 4 experimental replicates). The green manure was labelled with the stable isotopes 67Zn and 111Cd. For an efficient sample throughput, a method was provided and validated to determine enriched stable isotope ratios (67Zn:66Zn and 111Cd:110Cd) and the Zn and Cd concentrations in one analytical run. To this end, single collector ICP-MS analyses and stable isotope mass balances calculations were combined. Applying this method revealed that the addition of green manure increased neither Zn nor Cd concentrations in wheat grains due to biomass dilution effects. Isotope source tracing showed that the largest fraction of these metals in the wheat shoots derived from the soil in all treatments (Zn 87–99 %, Cd 94–98 %). Moreover, the addition of green manure increased the transfer of Zn and Cd from soil to wheat by a factor 1.9 for both elements. This increased transfer was likely related to a nitrogen fertilization effect that increased root and shoot biomass and thereby the soil exploration of the wheat. This study demonstrated how the fate and dynamics of multiple trace metals can be efficiently determined in soil–fertilizer–crop systems using isotope source tracing.

Comparative uptake, translocation and metabolism of phenamacril in crops under hydroponic and soil cultivation conditions

Many studies investigate the plant uptake and metabolism of xenobiotics by hydroponic experiments, however, plants grown in different conditions (hydroponic vs. soil) may result in different behaviors. To explore the potential differences, a comparative study on the uptake, translocation and metabolism of the fungicide phenamacril in crops (wheat/rice) under hydroponic and soil cultivation conditions was conducted. During 7–14 days of exposure, the translocation factors (TFs) of phenamacril were greatly overestimated in hydroponic-wheat (3.6–5.2) than those in soil-wheat systems (1.1–2.0), with up to 3.3 times of difference between the two cultivation systems, implying it should be cautious to extrapolate the results obtained from hydroponic to field conditions. M-144 was formed in soil pore water (19.1–29.9 μg/L) in soil-wheat systems but not in the hydroponic solution in hydroponics; M-232 was only formed in wheat shoots (89.7–103.0 μg/kg) under soil cultivation conditions, however, it was detected in hydroponic solution (20.1–21.2 μg/L), wheat roots (146.8–166.0 μg/kg), and shoots (239.2–348.1 μg/kg) under hydroponic conditions. The root concentration factors (RCFs) and TFs of phenamacril in rice were up to 2.4 and 3.6 times higher than that in wheat for 28 days of the hydroponic exposure, respectively. These results highlighted that cultivation conditions and plant species could influence the fate of pesticides in crops, which should be considered to better assess the potential accumulation and transformation of pesticides in crops.

Nighttime warming promotes copper translocation from root to shoot of wheat (Triticum aestivum L.) through enlarging root systems

Nighttime warming promotes copper translocation from root to shoot of wheat (Triticum aestivum L.) through enlarging root systems

Transcriptome-wide characterization of alternative splicing regulation in Najran wheat (Triticum aestivum) under salt stress

The process of alternative splicing (AS) has emerged as a crucial mechanism in plant responses to environmental stresses, contributing to the enhancement of the required transcriptome and proteome complexity. Despite the importance of AS, there remains a paucity of studies on the regulatory implications of AS in the responses of wheat to salt stress. In the current study, transcriptome-wide changes in AS profiles were established in roots and shoots of Najran wheat treated with 200 mM NaCl. Salt stress induced AS events increasing the complexity of the transcriptome; out of all expressed genes in all samples, 32,268 genes (22.5% of expressed genes) in the roots and 31,941 genes (23.1% of expressed genes) in the shoots were subjected to AS with 3’ Alternative splice site (A3) being the most frequent AS event and mutually exclusive exon (MX) being the least common event. Moreover, the results revealed that salt stress modulates AS patterns in a tissue-specific way where 82% of AS events were differentially expressed in either root or shoot tissues, participating in organ differentiation. In Total, 423 Differential AS events associated with cytoskeletal-related categories such as microtubule-based processes, actin filament-based movements, and cytoskeletal motor activity were identified in the roots. In contrast, 393 Differential AS events associated with biological categories related to metabolic and signalling processes such as catabolic processes, and response to gibberellin were identified in the shoots. The results presented in this study enhance our understanding of salt tolerance mechanisms in wheat and provide promising insights for future functional investigations and crop improvement efforts.

Biochemical and molecular responses of the ascorbate-glutathione cycle in wheat seedlings exposed to different forms of selenium

Biofortification aims to increase selenium (Se) concentration and bioavailability in edible parts of crops such as wheat (Triticum aestivum L.), resulting in increased concentration of Se in plants and/or soil. Higher Se concentrations can disturb protein structure and consequently influence glutathione (GSH) metabolism in plants which can affect antioxidative and other detoxification pathways. The aim of this study was to elucidate the impact of five different concentrations of selenate and selenite (0.4, 4, 20, 40 and 400 mg kg−1) on the ascorbate-glutathione cycle in wheat shoots and roots and to determine biochemical and molecular tissue-specific responses. Content of investigated metabolites, activities of detoxification enzymes and expression of their genes depended both on the chemical form and concentration of the applied Se, as well as on the type of plant tissue. The most pronounced changes in the expression level of genes involved in GSH metabolism were visible in wheat shoots at the highest concentrations of both forms of Se. Obtained results can serve as a basis for further research on Se toxicity and detoxification mechanisms in wheat. New insights into the Se impact on GSH metabolism could contribute to the further development of biofortification strategies.

Effect of Irrigation Scheduling and Different Sowing Dates on Growth and Yield of Wheat (Triticum aestivum L.)

The study was conducted at Acharya Narendra Deva University of Agriculture and Technology, Ayodhya (U.P.) Agronomy Research Farm in rabi season 2021-22. Twelve main plot treatments included 15th November, 25th November, and 5th December sowing dates, while four sub plot treatments included irrigation at 0.6, 0.8, 1.0, and 1.2 IW/CPE ratios. Split plot design was used for three replications. Under 15th November sowing, all growth, yield, and characteristics rose dramatically. Irrigating at 1.0 IW/CPE ratio increased wheat shoot m-2, plant height (cm), dry matter accumulation (g m-2), yield characteristics, grain and straw yield (q ha-1) considerably. Wheat yields were highest when sown on November 15. Under 15th November planting, water use efficiency was highest (9.85 kg ha-1mm-1). Out of all treatments, 15th Nov planting had the highest biological (128.21 q ha-1) and seed yield (51.43 q ha-1) and irrigation on 1.0 IW/CPE had the highest biological (127.18 q ha-1) and seed yield (50.83 Maximum Harvest Index was 40.11 percent with 15th November planting and 1.0 IW/CPE ratio irrigation (39.96%).

LONG-TERM (2005-2020) WINTER WHEAT PEST POPULATION DYNAMICS IN UKRAINE IN RESPONSE TO EFFECTS OF ACREAGE TREATED WITH INSECTICIDES AND CLIMATE CHANGE

We studied the long-term population dynamic`s (2005-2020) of six main insect pests of winter wheat (late wheat shoot fly, hessian fly, frit flies, cereal beetles, corn ground beetle and sun pest) in three climatic zones of Ukraine under conditions of increasing areas of application pesticides and global warming. The aim of the research was to investigate how these factors influence pest population dynamics. Comparison of sums of effective temperatures (SET) with standard values for different zones indicates significant climate warming over the past 15 years. Correlation analysis with two variables showed a general decrease in the numbers of most populations, especially in the steppe and forest-steppe zones.