Metal nanoparticles to improve the heat resilience in wheat (Triticum aestivumL.).

This study evaluated the efficacy of phytogenic silver and zinc nanoparticles in improving heat resilience in various wheat varieties. The silver and zinc nanoparticles were synthesized using plant leaf extract and characterized using various techniques. Four wheat varieties (DBW187, Black Wheat, DBW 50, and PBW 621) were subjected to field trials. The random block design was used, and nanoparticles in different concentrations were applied at various growth stages and morphologically, and yield parameters were recorded. UV-vis spectroscopy spectral analysis showed peaks for Ag nanoparticles at 420 nm wavelength and Zn nanoparticles at 240 and 350 nm wavelength, depicting the preliminary confirmation of nanoparticle synthesis. Electron microscopic analysis (TEM and SEM) provided morphological insights and confirmed synthesis of fine-sized particle mostly in a range between 10 and 60 nm. Energy dispersive x-ray analysis confirmed the elemental composition of the synthesized nanoparticles, with Ag and Zn elements detected in their respective samples. It also confirmed the oxide nature of synthesized ZnNPs. Dynamic light scattering analysis provided size distribution profiles, indicating average sizes of approximately 61.8 nm for Ag nanoparticles and 46.5 nm for Zn nanoparticles. The concentrations of Ag and Zn nanoparticles in the samples were found to be 196.3 ppm and 115.14 ppm, respectively, through atomic absorption spectroscopic analysis. Fourier transform infrared spectroscopy analysis revealed characteristic functional groups present in the nanoparticles. The results of field experiments established that Ag nanoparticles at 75 ppm concentration exhibited the most significant enhancements in plant growth. Conversely, Zn nanoparticles at a 100 ppm concentration demonstrated the most substantial improvements in the growth and yield of heat-stressed wheat varieties. The study concludes that optimized concentrations of silver and zinc nanoparticles can effectively improve heat stress resilience in wheat. These findings are promising to enhance abiotic stress resilience in crops.

Metabolic changes during wheat microspore embryogenesis induction using the highly responsive cultivar Svilena.

Androgenetically-derived haploids can be obtained by inducing embryogenesis in microspores. Thus, full homozygosity is achieved in a single generation, oppositely to conventional plant breeding programs. Here, the metabolite profile of embryogenic microspores of Triticum aestivum was acquired and integrated with transcriptomic existing data from the same samples in an effort to identify the key metabolic processes occurring during the early stages of microspore embryogenesis. Primary metabolites and transcription profiles were identified at three time points: prior to and immediately following a low temperature pre-treatment given to uninuclear microspores, and after the first nuclear division. This is the first time an integrative -omics analysis is reported in microspore embryogenesis in T. aestivum. The key findings were that the energy produced during the pre-treatment was obtained from the tricarboxylic acid (TCA) cycle and from starch degradation, while starch storage resumed after the first nuclear division. Intermediates of the TCA cycle were highly demanded from a very active amino acid metabolism. The transcription profiles of genes encoding enzymes involved in amino acid synthesis differed from the metabolite profiles. The abundance of glutamine synthetase was correlated with that of glutamine. Cytosolic glutamine synthetase isoform 1 was found predominantly after the nuclear division. Overall, energy production was shown to represent a major component of the de-differentiation process induced by the pre-treatment, supporting a highly active amino acid metabolism.

The effect of sulphur supplementation on cadmium phytotoxicity in wheat and lettuce: changes in physiochemical properties of roots and accumulation of phytochelatins.

Intensive sulphur fertilisation has been reported to improve the nutrient balance and growth of Cd-exposed plants, but the reasons of this phenomenon and the role of sulphur compounds in the resistance to cadmium are unclear. We investigated sulphur supplementation-induced changes in the surface properties of roots and the level of thiol peptides (PCs) in Cd-stressed Triticum aestivum L. (monocots clade) and Lactuca sativa L. (dicots clade) grown in nutrient solution. The combination of three sulphur (2 mM S-basic level, 6 or 9 mM S-elevated levels) and four cadmium (0, 0.0002, 0.02 or 0.04 mM Cd) concentrations was used. The physicochemical parameters of the roots were determined based on the apparent surface area (Sr), total variable surface charge (Q), cation exchange capacity (CEC) and surface charge density (SCD). In Cd-exposed plants supplied with sulphur, a different character and trend in the physicochemical changes (adsorption and ion exchange) of roots were noted. At the increased sulphur levels, as a rule, the Sr, CEC, Q and SCD values clearly increased in the lettuce but decreased in the wheat in the entire range of the Cd concentrations, except the enhanced Sr of wheat supplied with 6 mM S together with elevated (0.0002 mM) and unchanged (0.02, 0.04 mM Cd) value of this parameter at 9 mM S. This indicates a clade-specific and/or species-specific plant reaction. The 6 mM S appears to be more effective than 9 mM S in alleviation of the cadmium's toxic effects on roots. It was found that at 0.02 and 0.04 mM Cd, the use of 6 mM S limits the Cd accumulation in the roots of both species in comparison with the basic S fertilisation. Moreover, PC accumulation was much more efficient in wheat than in lettuce, and intensive sulphur nutrition generally induced biosynthesis of these chelating compounds. Physicochemical parameters together with quantitative and qualitative assessment of thiol peptides can be important indicators of the efficiency of root system functioning under cadmium stress. The differences between the species and the multidirectional character of the changes are a result of the involvement of a number of multi-level mechanisms engaged in the defence against metal toxicity.

An In Vitro Evaluation of Anti-inflammatory and Antioxidant Activities of Cocos nucifera and Triticum aestivum Formulation.

Background Medicinal plants are traditionally used in Ayurveda, Unani medicine, and Siddha as primary sources of drugs, and mankind has exploited the therapeutic properties of these herbs throughout history. Coconut (Cocos nucifera), a common ingredient of Indian sub-continental cuisine, has been proven to possess various medicinal properties; similarly, wheatgrass (Triticum aestivum) is of greater medicinal value and is known as the powerhouse of nutrients and vitamins. These have been used individually, but there is limited data on the synergistic use of these products. Thus, the present in vitro study was designed to prepare an oral gel from the extract of C. nucifera and T. aestivum and to assess its cumulative anti-inflammatory and antioxidant activity. Materials and methods C. nucifera extract and T. aestivum extract were prepared separately, and gel formulation was done. The formulated gel was tested for its anti-inflammatory and antioxidant activity. Results The results of the present study demonstrated that the anti-inflammatory property of the gel formulation was greater as compared to the standard (diclofenac), with the highest percentage of inhibition of 90.1% at 50 µl. With regard to the antioxidant property, we found that it was comparable to the standard (ascorbic acid) at various concentrations, with greater activity at 50 µl. Conclusion The oral gel formulation of coconut (C. nucifera) and wheatgrass (T. aestivum) showed better anti-inflammatory and a comparable antioxidant activity. Thus, this formulation may be employed as an adjunct to the commercially available oral gel preparations.

Integrated Analysis of Metabolome and Transcriptome Reveals Insights for Low Phosphorus Tolerance in Wheat Seedling.

Low phosphorus (LP) stress leads to a significant reduction in wheat yield, primarily in the reduction of biomass, the number of tillers and spike grains, the delay in heading and flowering, and the inhibition of starch synthesis and grouting. However, the differences in regulatory pathway responses to low phosphorus stress among different wheat genotypes are still largely unknown. In this study, metabolome and transcriptome analyses of G28 (LP-tolerant) and L143 (LP-sensitive) wheat varieties after 72 h of normal phosphorus (CK) and LP stress were performed. A total of 181 and 163 differentially accumulated metabolites (DAMs) were detected for G28CK vs. G28LP and L143CK vs. L143LP, respectively. Notably, the expression of pilocarpine (C07474) in G28CK vs. G28LP was significantly downregulated 4.77-fold, while the expression of neochlorogenic acid (C17147) in L143CK vs. L143LP was significantly upregulated 2.34-fold. A total of 4023 differentially expressed genes (DEGs) were acquired between G28 and L143, of which 1120 DEGs were considered as the core DEGs of LP tolerance of wheat after LP treatment. The integration of metabolomics and transcriptomic data further revealed that the LP tolerance of wheat was closely related to 15 metabolites and 18 key genes in the sugar and amino acid metabolism pathway. The oxidative phosphorylation pathway was enriched to four ATPases, two cytochrome c reductase genes, and fumaric acid under LP treatment. Moreover, PHT1;1, TFs (ARFA, WRKY40, MYB4, MYB85), and IAA20 genes were related to the Pi starvation stress of wheat roots. Therefore, the differences in LP tolerance of different wheat varieties were related to energy metabolism, amino acid metabolism, phytohormones, and PHT proteins, and precisely regulated by the levels of various molecular pathways to adapt to Pi starvation stress. Taken together, this study may help to reveal the complex regulatory process of wheat adaptation to Pi starvation and provide new genetic clues for further study on improving plant Pi utilization efficiency.

Comparative impact of nanoparticles on salt resistance of wheat plants.

When it comes to climate change, salt stress is a significant danger to agriculture and can lead to decreased crop yields due to various factors such as osmotic and ionic stress, as well as oxidative stress, disruption of hormone balance, and nutrient imbalance (Fig. 2). Despite this, there is a growing pressure to expand agriculture into salt-affected regions to meet the demands of a growing population.•Research has shown that supplementing plants with nanoparticles can help them adapt and alleviate the negative effects of salt stress.•Different types of nanoparticles and nanofertilizers have shown potential in managing salt stress. This review focuses on recent progress in using Fe3O4, ZnO, Al2O3 and CuO nanoparticles to improve salt tolerance in wheat plants and highlights future research directions in this area.•The study utilized nanoparticles to investigate their impact on plant morphology and photosynthesis intensity, including chlorophyll and carotenoid content, as well as light spectrum absorption in common wheat (Triticum aestivum L.).

Induction of silicon defences in wheat landraces is local, not systemic, and driven by mobilization of soluble silicon to damaged leaves.

In response to herbivory, many grasses, including crops such as wheat, accumulate significant levels of silicon (Si) as an antiherbivore defence. Damage-induced increases in Si can be localized in damaged leaves or be more systemic, but the mechanisms leading to these differences in Si distribution remain untested. Ten genetically diverse wheat landraces (Triticum aestivum) were used to assess genotypic variation in Si induction in response to mechanical damage and how this was affected by exogenous Si supply. Total and soluble Si levels were measured in damaged and undamaged leaves as well as in the phloem to test how Si was allocated to different parts of the plant after damage. Localized, but not systemic, induction of Si defences occurred, and was more pronounced when plants had supplemental Si. Damaged plants had significant increases in Si concentration in their damaged leaves, while the Si concentration in undamaged leaves decreased, such that there was no difference in the average Si concentration of damaged and undamaged plants. The increased Si in damaged leaves was due to the redirection of soluble Si, present in the phloem, from undamaged to damaged plant parts, potentially a more cost-effective defence mechanism for plants than increased Si uptake.

Development and marker-trait relationships of functional markers for glutamine synthetase GS1 and GS2 homoeogenes in bread wheat.

GS1 and GS2 genes encode, respectively, the main cytosolic and the plastidic isoforms of glutamine synthetase (GS). In the present study, the wheat GS1 and GS2 homoeogenes located in the A, B and D genome chromosomes have been sequenced in a group of 15 bread wheat varieties including landraces, old commercial varieties and modern cultivars. Phenotypic characterization by multi-environment field trials detected significant effects of specific GS homoeogenes on three of the seven agronomic and grain quality traits analyzed. Based on the gene sequence polymorphisms found, biallelic molecular markers that could facilitate marker-assisted breeding were developed for genes GS1A, GS2A and GS2D. The remaining genes encoding main wheat GS were excluded because of being monomorphic (GS1D) or too polymorphic (GS1B and GS2B) in the sequencing panel varieties. A collection of 187 Spanish bread wheat landraces was genotyped for these gene-based molecular markers. Data analyses conducted with phenotypic records reported for this germplasm collection in López-Fernández et al. (Plants-Basel 10: 620, 2021) have revealed the beneficial influence of some individual alleles on thousand-kernel weight (TKW), kernels per spike (KS) and grain protein content. Furthermore, genetic interactions between GS1A, a cytosolic GS isoform coding gene, and GS2A or GS2D, plastidic GS enzyme coding genes, were found to affect TKW and KS. The finding that some alleles at one locus may mask the effect of positive alleles at hypostatic GS loci should be kept in mind if gene pyramiding strategies are attempted for the improvement of N-use efficiency-related traits. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01354-0.

PHOSPHORUS-STARVATION TOLERANCE 1 (OsPSTOL1) is prevalent in upland rice and enhances root growth and hastens low phosphate signaling in wheat.

PHOSPHORUS-STARVATION TOLERANCE 1 (OsPSTOL1) is a variably present gene that benefits crown root growth and phosphorus (P) sufficiency in rice (Oryza sativa). To explore the ecophysiological importance of this gene, we performed a biogeographic survey of landraces and cultivars, confirming that functional OsPSTOL1 alleles prevail in low nutrient and drought-prone rainfed ecosystems, whereas loss-of-function and absence haplotypes predominate in control-irrigated paddy varieties of east Asia. An evolutionary history analysis of OsPSTOL1 and related genes in cereal, determined it and other genes are kinase-only domain derivatives of membrane-associated receptor like kinases. Finally, to evaluate the potential value of this kinase of unknown function in another Gramineae, wheat (Triticum aestivum) lines overexpressing OsPSTOL1 were evaluated under field and controlled low P conditions. OsPSTOL1 enhances growth, crown root number, and overall root plasticity under low P in wheat. Survey of root and shoot crown transcriptomes at two developmental stages identifies transcription factors that are differentially regulated in OsPSTOL1 wheat that are similarly controlled by the gene in rice. In wheat, OsPSTOL1 alters the timing and amplitude of regulators of root development in dry soils and hastens induction of the core P-starvation response. OsPSTOL1 and related genes may aid more sustainable cultivation of cereal crops.

Nutritional and tissue-specific regulation of cytochrome P450 CYP711A MAX1 homologues and strigolactone biosynthesis in wheat.

Strigolactones (SLs) are a class of phytohormones regulating branching/tillering, and their biosynthesis has been associated with nutritional signals and plant adaptation to nutrient-limiting conditions. The enzymes in the SL biosynthetic pathway downstream of carlactone are of interest as they are responsible for structural diversity in SLs, particularly cytochrome P450 CYP711A subfamily members, such as MORE AXILLARY GROWTH1 (MAX1) in Arabidopsis. We identified 13 MAX1 homologues in wheat, clustering in four clades and five homoeologous subgroups. The utilization of RNA-sequencing data revealed a distinct expression pattern of MAX1 homologues in above- and below-ground tissues, providing insights into the distinct roles of MAX1 homologues in wheat. In addition, a transcriptional analysis showed that SL biosynthetic genes were systematically regulated by nitrogen supply. Nitrogen limitation led to larger transcriptional changes in the basal nodes than phosphorus limitation, which was consistent with the observed tillering suppression, as wheat showed higher sensitivity to nitrogen. The opposite was observed in roots, with phosphorus limitation leading to stronger induction of most SL biosynthetic genes compared with nitrogen limitation. The observed tissue-specific regulation of SL biosynthetic genes in response to nutritional signals is likely to reflect the dual role of SLs as rhizosphere signals and branching inhibitors.

Field application of silicon alleviates drought stress and improves water use efficiency in wheat.

Detrimental impacts of drought on crop yield have tripled in the last 50 years with climate models predicting that the frequency of such droughts will intensify in the future. Silicon (Si) accumulation, especially in Poaceae crops such as wheat (Triticum aestivum L.), may alleviate the adverse impacts of drought. We have very limited information, however, about whether Si supplementation could alleviate the impacts of drought under field conditions and no studies have specifically manipulated rainfall. Using field-based rain exclusion shelters, we determined whether Si supplementation (equivalent to 39, 78 and 117 kg ha-1) affected T. aestivum growth, elemental chemistry [Si, carbon (C) and nitrogen (N)], physiology (rates of photosynthesis, transpiration, stomatal conductance, and water use efficiency) and yield (grain production) under ambient and drought (50% of ambient) rainfall scenarios. Averaged across Si treatments, drought reduced shoot mass by 21% and grain production by 18%. Si supplementation increased shoot mass by up to 43% and 73% in ambient and drought water treatments, respectively, and restored grain production in droughted plants to levels comparable with plants supplied with ambient rainfall. Si supplementation increased leaf-level water use efficiency by 32-74%, depending on Si supplementation rates. Water supply and Si supplementation did not alter concentrations of C and N, but Si supplementation increased shoot C content by 39% and 83% under ambient and drought conditions, respectively. This equates to an increase from 6.4 to 8.9 tonnes C ha-1 and from 4.03 to 7.35 tonnes C ha-1 under ambient and drought conditions, respectively. We conclude that Si supplementation ameliorated the negative impacts of drought on T. aestivum growth and grain yield, potentially through its beneficial impacts on water use efficiency. Moreover, the beneficial impacts of Si on plant growth and C storage may render Si supplementation a useful tool for both drought mitigation and C sequestration.

The Influence of Biostimulants Used in Sustainable Agriculture for Antifungal Protection on the Chemical Composition of Winter Wheat Grain.

Field studies were conducted from 2016 to 2019 (south-eastern Poland; 49°58'40.6″ N 22°33'11.3″ E) with the aim to identify the chemical composition of winter wheat grain upon foliar application of biostimulants, of which PlanTonic BIO (containing nettle and willow extracts) showed antifungal activity. The main chemical compositions and their spatial distribution in wheat grain were characterized by Raman spectroscopy technique. It was established that applied biostimulants and hydro-thermal conditions changed the chemical composition of the grain during all the studied years. A similar chemical composition of the grain was achieved in plants treated with synthetic preparations, including both intensive and extensive variants. The second group, in terms of an increase in fatty acid content, consists of grains of plants treated with biostimulants PlanTonic BIO, PlanTonic BIO + Natural Crop and PlanTonic BIO + Biofol Plex. The future of using biostimulants in crop production, including those containing salicylic acid and nettle extracts, appears to be a promising alternative to synthetic crop protection products.

Phosphorus Fertilizers from Sewage Sludge Ash and Animal Blood as an Example of Biobased Environment-Friendly Agrochemicals: Findings from Field Experiments.

Wastes of biological origin from wastewater treatment systems and slaughterhouses contain substantial amounts of phosphorus (P) with high recovery potential and can contribute to alleviating the global P supply problem. This paper presents the performance of fertilizer (AF) and biofertilizer (BF) from sewage sludge ash and animal blood under field conditions. BF is AF incorporated with lyophilized cells of P-solubilizing bacteria, Bacillus megaterium. In the experiments with spring or winter wheat, the biobased fertilizers were compared to commercial P fertilizer, superphosphate (SP). No P fertilization provided an additional reference. Fertilizer effects on wheat productivity and on selected properties of soil were studied. BF showed the same yield-forming efficiency as SP, and under poorer habitat conditions, performed slightly better than AF in increasing yield and soil available P. Biobased fertilizers applied at the P rate up to 35.2 kg ha-1 did not affect the soil pH, did not increase As, Cd, Cr, Ni, and Pb content, and did not alter the abundance of heterotrophic bacteria and fungi in the soil. The findings indicate that biobased fertilizers could at least partially replace conventional P fertilizers. Research into strain selection and the proportion of P-solubilizing microorganisms introduced into fertilizers should be continued.

Comparative transcriptome and DNA methylation analysis in temperature-sensitive genic male sterile wheat BS366.

BACKGROUND: Known as the prerequisite component for the heterosis breeding system, the male sterile line determines the hybrid yield and seed purity. Therefore, a deep understanding of the mechanism and gene network that leads to male sterility is crucial. BS366, a temperature-sensitive genic male sterile (TGMS) line, is male sterile under cold conditions (12 °C with 12 h of daylight) but fertile under normal temperature (20 °C with 12 h of daylight). RESULTS: During meiosis, BS366 was defective in forming tetrads and dyads due to the abnormal cell plate. During pollen development, unusual vacuolated pollen that could not accumulate starch grains at the binucleate stage was also observed. Transcriptome analysis revealed that genes involved in the meiotic process, such as sister chromatid segregation and microtubule-based movement, were repressed, while genes involved in DNA and histone methylation were induced in BS366 under cold conditions. MethylRAD was used for reduced DNA methylation sequencing of BS366 spikes under both cold and control conditions. The differentially methylated sites (DMSs) located in the gene region were mainly involved in carbohydrate and fatty acid metabolism, lipid metabolism, and transport. Differentially expressed and methylated genes were mainly involved in cell division. CONCLUSIONS: These results indicated that the methylation of genes involved in carbon metabolism or fatty acid metabolism might contribute to male sterility in BS366 spikes, providing novel insight into the molecular mechanism of wheat male sterility.

Transcriptome and proteome profiling revealed molecular mechanism of selenium responses in bread wheat (Triticum aestivum L.).

BACKGROUND: Although selenium (Se) plays important roles in scavenging free radicals, alleviating oxidative stresses, and strengthening immune system, the knowledge about Se responses in bread wheat is still limited. In order to clarify the molecular mechanism of Se responses in bread wheat, 2-week-old wheat seedlings of cultivar 'Jimai22' treated with 10 µM disodium selenate (Na2SeO4) for 0, 3, and 24 h were collected and analyzed by transcriptional sequencing and tandem mass tag-based (TMT) quantitative proteomics. RESULTS: At least 11,656 proteins and 133,911 genes were identified, and proteins including ATP sulfurylase (APS), cysteine synthase (CS), SeCys lyase, sulfate transporters, glutathione S-transferase (GSTs), glutathione peroxidase (GSH-Px), glutaredoxins (GRXs), superoxide dismutases (SODs), catalases (CATs), heat shock proteins (HSPs), UDP-glycose flavonoid glycosyltransferases (UFGTs), sucrose-6-phosphate hydrolases (Suc-6-PHs), archaeal phosphoglucose isomerases (APGIs), malate synthases (MSs), and endo-1,4-beta-xylanase (Xyn) in Se accumulation, ROS scavenging, secondary metabolism, and carbohydrate metabolism were significantly differently expressed. CONCLUSIONS: This is the first complementary analyses of the transcriptome and proteome related with selenium responses in bread wheat. Our work enhances the understanding about the molecular mechanism of selenium responses in bread wheat.

Extract of Triticum aestivum Sprouts Suppresses Acetaminophen-Induced Hepatotoxicity in Mice by Inhibiting Oxidative Stress.

Wheat (Triticum aestivum L.) is the oldest known food crop, and many studies have reported that wheat shoots (i.e., wheatgrass) possess anti-cancer, anti-inflammatory, and antioxidant activities. However, the potentially ameliorative effect of wheat shoots on hepatotoxicity caused by high doses of N-acetyl-para-aminophenol (acetaminophen, APAP) has yet to be reported. C57BL/6 mice received daily oral TAE (100 or 200 mg/kg), positive control (silymarin 100 mg/kg), or negative control (saline vehicle) treatments for 7 days prior to intraperitoneal APAP injection. Histological, serum (ELISA), Western blotting, and quantitative PCR analyses of excised liver tissues were then performed. Pre-treatment with TAE (100 or 200 mg/kg) ameliorated APAP-induced pathological damage (i.e., hepatotoxic lesions), reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and also ameliorated APAP-induced increases in oxidative stress, thereby inhibiting oxidative liver damage and reducing the expression of inflammatory cytokines. In addition, TAE pre-treatment inhibited the expression of Cytochrome P4502E1 (CYP2E1), which is a key enzyme in the onset of APAP-induced hepatotoxicity, suppressed the expression of the target proteins regulated by the antioxidant enzyme Nrf2, and suppressed hepatocyte apoptosis. These findings suggest that TAE is an attractive therapeutic candidate that exhibits potential hepatoprotective activity by inhibiting oxidative stress, inflammation, apoptosis, and liver damage.

Impacts of Nitrogen Deficiency on Wheat (Triticum aestivum L.) Grain During the Medium Filling Stage: Transcriptomic and Metabolomic Comparisons.

Nitrogen (N) supplementation is essential to the yield and quality of bread wheat (Triticum aestivum L.). The impact of N-deficiency on wheat at the seedling stage has been previously reported, but the impact of distinct N regimes applied at the seedling stage with continuous application on filling and maturing wheat grains is lesser known, despite the filling stage being critical for final grain yield and flour quality. Here, we compared phenotype characteristics such as grain yield, grain protein and sugar quality, plant growth, leaf photosynthesis of wheat under N-deficient and N-sufficient conditions imposed prior to sowing (120 kg/hm2) and in the jointing stage (120 kg/hm2), and then evaluated the effects of this continued stress through RNA-seq and GC-MS metabolomics profiling of grain at the mid-filling stage. The results showed that except for an increase in grain size and weight, and in the content of total sugar, starch, and fiber in bran fraction and white flour, the other metrics were all decreased under N-deficiency conditions. A total of 761 differentially expressed genes (DEGs) and 77 differentially accumulated metabolites (DAMs) were identified. Under N-deficiency, 51 down-regulated DEGs were involved in the process of impeding chlorophyll synthesis, chloroplast development, light harvesting, and electron transfer functions of photosystem, which resulted in the SPAD and Pn value decreased by 32 and 15.2% compared with N-sufficiency, inhibited photosynthesis. Twenty-four DEGs implicated the inhibition of amino acids synthesis and protein transport, in agreement with a 17-42% reduction in ornithine, cysteine, aspartate, and tyrosine from metabolome, and an 18.6% reduction in grain protein content. However, 14 DEGs were implicated in promoting sugar accumulation in the cell wall and another six DEGs also enhanced cell wall synthesis, which significantly increased fiber content in the endosperm and likely contributed to increasing the thousands-grain weight (TGW). Moreover, RNA-seq profiling suggested that wheat grain can improve the capacity of DNA repair, iron uptake, disease and abiotic stress resistance, and oxidative stress scavenging through increasing the content levels of anthocyanin, flavonoid, GABA, galactose, and glucose under N-deficiency condition. This study identified candidate genes and metabolites related to low N adaption and tolerance that may provide new insights into a comprehensive understanding of the genotype-specific differences in performance under N-deficiency conditions.

Biomimetic synthesis of functional silver nanoparticles using hairy roots of Panax ginseng for wheat pathogenic fungi treatment.

Presently, multifunctional silver nanoparticles (AgNPs) show a rapid growth in various commercial applications, leading to increasing demand for new eco-friendly manufacturing technologies. An array of genetic engineering tools can be used to increase the yield in the production of AgNPs using various biological systems. The present study reports a green chemistry approach for the biological synthesis of AgNPs using extracts from non-transformed callus, rolC-transgenic callus and hairy roots of Panax ginseng and an evaluation of their efficacy against crop-damaging fungal pathogens. All types of ginseng cell lines promote the reduction of silver nitrate and formation of spherical AgNPs with an average diameter of 50-90 nm. Notably, hairy root extract possessed the maximal reduction potential among the studied cell lines probably due to higher secondary metabolite content. The biosynthesized nanoparticles were highly toxic against several wheat fungal pathogens including Fusarium graminearum, F. avenaceum, F. poae, and F. sporotrichioides, which are associated with fusarium head blight disease in cereals. Furthermore, the antifungal activity of nanosilver was successfully utilized for surface sterilization of infected wheat kernels without any negative effect on seed germination capability.

High phosphorus fertilization changes the speciation and distribution of manganese in wheat grains grown in a calcareous soil.

The physiological disorders in humans resulting from the excess dietary intake of manganese (Mn) via whole-grain food has attracted considerable attention. However, the speciation and bioavailability of Mn in wheat grains and their response to different phosphorus (P) fertilization rates are still unclear. In the current study, using a long-term field trial with P application rates of 0, 21.8, 43.6, 65.5 and 87.3 kg/ha, we examined changes in the concentration, distribution, and speciation of Mn of wheat grains using synchrotron-based X-ray fluorescence microscopy and X-ray absorption spectroscopy. The total Mn concentration in grains was found to be increased by phosphorus fertilization, especially in embryo in the form of Mn(II), but this phosphorus fertilization also decreased Mn concentrations in the nucellar projection. In this study, the speciation of Mn in different wheat grain tissues was examined, and results indicate that in calcareous soils, high rates of P fertilizers can increase Mn concentrations in wheat grain, including Mn which is likely to be of high bioavailability, and thus may increase the risk for human to expose to high Mn intake via whole-grain food.

Spikelet movements, anther extrusion and pollen production in wheat cultivars with contrasting tendencies to cleistogamy.

BACKGROUND: Cleistogamic flowers are a main barrier in pollen dispersal for cross-pollination necessary in wheat hybrid breeding. The aim of our study was to gain new knowledge on the biology of wheat flowering, in particular on the differences between the cleisto- and chasmogamic forms which has certainly cognitive significance, but it can also be used in practice when seeking a female and male ideotypes for cross hybridization. RESULTS: We characterized the most significant features defining the flowering specificity in two wheat cultivars with contrasting tendency to cleistogamy: Piko (chasmogamous) and Dacanto (cleistogamous). In the field observations we assessed diurnal pattern of anther extrusion and anther extrusion capacity. For the first time we adapted the time lapse method for measuring kinetics of the spikelet movement and 3-D image correlation technique for the non-invasive measurements of potential deformations of the spikelet lemmas. We found that the two cultivars differ in the potential of pollen dispersion for-cross-pollination and in the spikelet kinetics. We also described some anatomical traits that can have potential functional role in floret opening. None of the cultivars showed any symptoms of lemma surface deformation. CONCLUSIONS: The cleistogamic and chasmogamic wheat cultivars differ significantly in the potential for pollen dispersion for cross-pollination, which is mainly related to anther extrusion capacity. Although none of these features differentiated the cultivars clearly, we assume, based on spikelet kinetics and the lack of lemmas surface deformation, that the water transport and turgor of cells is essential for the floret opening and anther extrusion in wheat. The search for parental ideotype should be supported by marker assisted selection, e.g. based of polymorphisms in genes related to aquaporin biosynthesis.