Concentrations Of Plant Hormones Research Articles

Combining Physiology and Transcriptome Data Screening for Key Genes in Actinidia arguta Response to Waterlogging Stress

Actinidia arguta is a cold-resistant fruit tree but intolerant to waterlogging. Waterlogging stress is the major abiotic stress in A. arguta growth, and several pathways are involved in the response mechanisms. Fifteen physiological indices and transcriptome data of two A. arguta cultivars, which showed two forms under waterlogging, were used to identify the major factor following the leaf senescence in waterlogging. Through principal component analysis (PCA) of 15 physiological indices in ‘Kuilv’ and ‘Lvwang’, the hormone contents were selected as the most important principal component (PCA 2) out of four components in response to waterlogging stress. According to the analysis of transcriptome data, 21,750 differentially expressed genes were identified and 10 genes through WGCNA, including hormone metabolism and sucrose metabolism, were screened out on the 6th day of waterlogging. In particular, the ABA signal transduction pathway was found to be closely related to the response to waterlogging based on the correlation analysis between gene expression level and plant hormone content, which may have regulated physiological indicators and morphological changes together with other hormones. Overall, the phenomenon of leaves falling induced by ABA might be a protective mechanism. The results provided more insights into the response mechanism of coping with waterlogging stress in A. arguta.

Phytohormonal balance and differential gene expression in chronically irradiated Scots pine populations from the chernobyl affected zone.

The impact of chronic radiation exposure on phytohormone content and expression of phytohormone- and stress-related genes of Scots pine in the zone affected by the Chernobyl accident was studied. Needle samples were collected from three plots with contrasting levels of radioactive contamination in the Polesye State Radiation-Ecological Reserve, Republic of Belarus, and two reference plots in the Kozeluzhsky forest in June 2022. The experimental plots were located within the artificial plantations of Scots pine established in 1982, before the accident in 1986. The activity of radionuclides 137Cs, 90Sr, 241Am, 238Pu, and 239+240Pu in soil and needles ensured dose rates ranging from 3.3 to 87 mGy × year-1, while at the reference plots, the range was 0.7‒0.8 mGy × year-1. Concentrations of plant hormones, including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), zeatin, and abscisic acid (ABA) in needles were evaluated using high-performance liquid chromatography (HPLC). We demonstrate that chronic radiation exposure is a significant stress factor that affects both phytohormonal balance and the expression of some important phytohormone- and stress-related genes. We found a tendency toward decreased ABA and auxin concentrations in trees from plots contaminated with radionuclides. The ratio (IAA + IBA + zeatin)/ABA was drastically raised at the most contaminated plots Masany and Kulazhin, reflecting the functional rearrangements of cellular metabolism that ensure plant adaptation under chronic radiation exposure. Changes in gene expression indicated modulation of ABA and Ca2+ signalling pathways, decreased potential of zeatin biosynthesis, and activation of heat shock proteins biosynthesis.

Mesoporous carbon hollow spheres based sensitive SPME probes for in vivo sampling analysis of selected plant hormones in Chinese aloes

Phytohormones are a class of endogenous substances that separately or synergistically regulate the growth, development, and differentiation of plants. Accurately and efficiently detecting and monitoring the concentration of plant hormones in living plants is of significant importance. Herein, a novel mesoporous carbon hollow spheres (MCHS)-based in vivo solid phase microextraction (SPME) probe was designed for in vivo sampling of plant hormones. The designed MCHS features the advantages of high surface area, porous shells, and large hollow spaces, facilitating the dynamic adsorption and enrichment of target phytohormone. In addition, a cationic polyelectrolyte, (poly (diallyl dimethyl ammonium chloride) (PDDA), was further modified onto the MCHS to expedite the extraction process by electrostatic interaction. Utilizing the MCHS@PDDA probe in combination with HPLC-MS/MS facilitated the continuous monitoring of three plant hormones (abscisic acid (ABA), indole-3-acetic acid (IAA), and gibberellin (GA3)) in Chinese aloe. The detection limit of this method was 0.016–0.090 μg/L, the linear range was 10–1000 μg/L, and both the RSD of the single probe (n = 6) and probe-to-probe test (n = 6) were less than 7.2 %. This method had excellent accuracy and good reproducibility comparable to the traditional sample pretreatment method. Ultimately, this established in-vivo SPME method was successfully adopted to quantify three selected plant hormones in living Chinese Aloes, providing a new method for the long-term monitoring of endogenous active substances in living system.

Ectopic Expression of AetPGL from Aegilops tauschii Enhances Cadmium Tolerance and Accumulation Capacity in Arabidopsis thaliana.

Cadmium (Cd) is a toxic heavy metal that accumulates in plants, negatively affecting their physiological processes, growth, and development, and poses a threat to human health through the food chain. 6-phosphogluconolactonase (PGL) is a key enzyme in the Oxidative Pentose Phosphate Pathway(OPPP) in plant cells, essential for cellular metabolism. The OPPP pathway provides energy and raw materials for organisms and is involved in antioxidant reactions, lipid metabolism, and DNA synthesis. This study describes the Cd responsive gene AetPGL from Aegilops tauschii. Overexpression of AetPGL under Cd stress increased main root length and germination rate in Arabidopsis. Transgenic lines showed higher antioxidant enzyme activities and lower malondialdehyde (MDA) content compared to the wild type. The transgenic Arabidopsis accumulated more Cd in the aboveground part but not in the underground part. Expression levels of AtHMA3, AtNRAMP5, and AtZIP1 in the roots of transgenic plants increased under Cd stress, suggesting AetPGL may enhance Cd transport from root to shoot. Transcriptome analysis revealed enrichment of differentially expressed genes (DEGs) in the plant hormone signal transduction pathway in AetPGL-overexpressing plants. Brassinosteroids (BR), Gibbenellin acid (GA), and Jasmonic acid (JA) contents significantly increased after Cd treatment. These results indicate that AetPGL may enhance Arabidopsis' tolerance to Cd by modulating plant hormone content. In conclusion, AetPGL plays a critical role in improving cadmium tolerance and accumulation and mitigating oxidative stress by regulating plant hormones, providing insights into the molecular mechanisms of plant Cd tolerance.

The Spotted Lanternfly Contains High Concentrations of Plant Hormones in its Salivary Glands: Implications in Host Plant Interactions.

The spotted lanternfly (SLF), Lycorma delicatula is an invasive species in the United States that has emerged as a significant pest in vineyards. This polyphagous insect causes significant damage to grapevines and tree of heaven (TOH). SLF feeds voraciously on plant tissues using its piercing and sucking mouthparts through which it injects saliva and uptakes plant sap. Despite its impact, research on fundamental mechanisms mediating SLF interactions with their predominant hosts is limited. This study documents the morphology of salivary glands and quantifies plant hormones in salivary glands of SLF adults fed on grapevines and TOH using Liquid Chromatography-Mass Spectrometry (LC/MS). SLF adults have one pair of large salivary glands, ranging from 10 to 15mm in length that extend from the insect's head to the last sections of the abdomen. The salivary glands of SLF contain salicylic acid (89 ng/g), abscisic acid (6.5 ng/g), 12-oxo-phytodienoic acid (5.7 ng/g), indole-3-acetic acid (2 ng/g), jasmonic acid (0.6 ng/g), jasmonic acid isoleucine (0.037 ng/g), and the cytokinin ribosides trans-zeatin (0.6 ng/g) and cis-zeatin (0.1 ng/g). While the concentrations of these hormones were similar in insects fed on grapevines and TOH, abscisic acid was more abundant in insects fed on grapevines, and jasmonic acid isoleucine was only detected in insects fed on grape. These results are discussed in the context of the possible implications that these hormones may have on the regulation of plant defenses. This study contributes to our understanding of the composition of SLF saliva and its potential role in plant immunity.

Research on the rapid tissue breeding technology of the endangered plant Cibotium barometz (L.) J. Sm.

Cibotium barometz (L.) J. Sm., a fern, holds significant value in traditional Chinese medicine. This research aimed to establish a rapid tissue breeding technology for Cibotium barometz (L.) and provide a theoretical basis for its artificial breeding and industrial planting. The optimum conditions for spores germination were selected, including both the best sterilization time and the ideal spore germination medium. Subsequently, the optimal medium for proliferation and differentiation were chosen, and the optimal concentration of plant hormones was screened to determine the optimal medium. The rooting experiment was performed in two single-factor experiments by using differentiated sporophytes as materials. These experiments showed that the optimal sterilization time was 11 min and the best medium for germination was 1/8MS + 0.02 mg/L IAA. MS medium was suitable for proliferation, while WPM medium was suitable for sporophyte differentiation. The best medium for growth was MS + 1.0 mg/L IAA + 0.5 mg/L 6-BA. In the absence of sucrose, the seedlings barely grew and failed to differentiate into sporophytes. They showed optimal growth and differentiation at a sucrose concentration of 20 g/L. The plant growth regulators plant growth regulators used, including IAA, NAA, 6-BA, and GA3, showed more effective differentiation, wherease KT had a slightly weaker effect. The rooting rate reached the maximum when the concentrations of ABT and IBA were at 1.5 mg•L− 1 and IAA was at 1.0 mg•L− 1. The IBA had a significant effect on the average and the longest root length, while the three PGRs had no obvious effect on the average or maximum diameter. Plant tissue culture seedlings still have good genetic stability after subsequent generation. In this study, the optimal cultivation conditions for rapid breeding technology in tissue culture, covering stages from germination and growth to differentiation and rooting, were obtained. Moreover, sporophytes were successfully transplanted to the external environment. This study provided a theoretical reference for the industrial planting of C. barometz.

Cost-effective Phytohormone Extraction of Sargassum swartzii from the Persian Gulf Using Magnetic Ionic Liquid.

Algae extracts are utilized as biofertilizers instead of chemical ferti-lizers in agriculture. Further, algae are known to possess a high content of plant hormones, such as gibberellin, salicylic acid, abscisic acid, and brassinosteroids. The main objective of this study was to increase the extraction yield and simulta-neously extract hormones required for plant growth from Sargassum swartzii using Magnetic recoverable ionic liquid (IL). In this study, extraction was performed by acidic digestion with acetic acid and then alkaline digestion with potassium hydroxide. The results showed the ionic liquid effect in extraction yield by 266 percent. The extracted phytohormones were analyzed using high-performance liquid chromatography (HPLC) methods. High levels of gibberellin, salicylic acid, abscisic acid, and brassinosteroids in improved algae extraction showed that seaweed extract could be used as environmentally friendly liquid bio-fertilizers to replace chemical fertilizers and could play a crucial role in organic farming for sustainable agriculture. Additionally, the recoverability of ionic liquid eight times with negligible leaching proved the introduced procedure to be cost-effective. The reported procedure for algae extraction improved by using an acidic/primary ionic liquid environment. This procedure is economical because of the simple reusability of ionic liquid due to its magnetic features.

Two Carya Species, Carya hunanensis and Carya illinoinensis, Used as Rootstocks Point to Improvements in the Heat Resistance of Carya cathayensis.

Grafting as a crucial horticultural technique has been widely used in the cultivation of Carya cathayensis (Chinese hickory), which is a unique and important economic tree in the northeast of Zhejiang Province and the south of Anhui Province. However, the existing literature lacks research on the potential impact of various rootstocks on the thermal tolerance of Chinese hickory. The objectives of this study were to evaluate heat tolerance in four distinct groups of Chinese hickory, including C. cathayensis grafted onto Carya hunanensis and Carya illinoinensis, one self-grafted group (C. cathayensis grafted onto C. cathayensis), and one non-grafted group (C. cathayensis). We examined photosynthesis parameters, phytohormones, and differentially expressed genes in the four various hickory groups subjected to 25 °C, 35 °C, and 40 °C heat stress (HS). The results demonstrated that grafting onto C. hunanensis and C. illinoinensis exhibited a higher net photosynthetic rate and stomatal conductance, lower intercellular CO2 concentration, and smaller changes in plant hormone content compared to self-grafted and non-grafted group under HS. The transcriptome results revealed that the majority of differentially expressed genes (DEGs) associated with photosynthetic pathways exhibited downregulation under HS, while the degree of variation in grafted groups using C. hunanensis and C. illinoinensis as rootstocks was comparatively lower than that observed in self-grafted and non-grafted groups. The alteration in the expression patterns of DEGs involved in plant hormone synthesis and metabolism under HS corresponded to changes in plant hormone contents. Overall, Chinese hickory grafted onto C. hunanensis and C. illinoinensis exhibited enhanced resistance to high-temperature stress at the juvenile stage.

Postharvest white light combined with different UV-B doses differently promotes anthocyanin accumulation and antioxidant capacity in mango peel

Fruit peel color is an important index of mango fruit quality. Therefore, increasing the anthocyanin accumulation and improving coloration in red mango are crucial for mango industry. The anthocyanin accumulation in mango is light-regulated. However, the effect of white light combined with different doses of UV-B on anthocyanin biosynthesis has not been clarified. Also lacking is a comprehensive analysis of responses of mango fruit peel to UV-B/white light treatments. In this study, green mature ‘Guifei’ mango fruits were subjected to white light combined with low (WL + UV-BL) or high dose UV-B (WL + UV-BH). Anthocyanin concentration, anthocyanin-related gene expression, reactive oxygen species (ROS), antioxidant, and plant hormone concentrations, and antioxidant enzyme activity were measured. The results showed that especially a WL + UV-BH regimen promoted anthocyanin formation in mango peel. Anthocyanin- and light signal-related gene expression, ROS content, antioxidant enzyme activity, antioxidant concentrations, and total antioxidant capacity were also increased by UV-B/white light. Such treatments led to higher concentrations of jasmonic acid and cytokinin, but decreased content of 1-aminocyclopropane-1-carboxylic acid and salicylic acid. Commercially, our findings may contribute to improving the commercial quality of mango. Scientifically, the present data sheds light on the mango fruit peel-specific molecular and physiological response network under UV-B/white light treatments.

Why can Mikania micrantha cover trees quickly during invasion?

The invasion of Mikania micrantha by climbing and covering trees has rapidly caused the death of many shrubs and trees, seriously endangering forest biodiversity. In this study, M. micrantha seedlings were planted together with local tree species (Cryptocarya concinna) to simulate the process of M. micrantha climbing under the forest. We found that the upper part of the M. micrantha stem lost its support after climbing to the top of the tree, grew in a turning and creeping manner, and then grew branches rapidly to cover the tree canopy. Then, we simulated the branching process through turning treatment. We found that a large number of branches had been formed near the turning part of the M. micrantha stem (TP). Compared with the upper part of the main stem (UP), the contents of plant hormones (auxin, cytokinin, gibberellin), soluble sugars (sucrose, glucose, fructose) and trehalose-6-phosphate (T6P) were significantly accumulated at TP. Further combining the transcriptome data of different parts of the main stem under erect or turning treatment, a hypothetical regulation model to illustrate how M. micrantha can quickly cover trees was proposed based on the regulation of sugars and hormones on plant branching; that is, the lack of support after ascending the top of the tree led to turning growth of the main stem, and the enhancement of sugars and T6P levels in the TP may first drive the release of nearby dormant buds. Plant hormone accumulation may regulate the entrance of buds into sustained growth and maintain the elongation of branches together with sugars to successfully covering trees.

Metabolic regulation mechanism of melatonin for reducing cadmium accumulation and improving quality in rice

Melatonin acts as a potential regulator of cadmium (Cd) tolerance in rice. However, its practical value in rice production remains unclear. To validate the hypothesis that melatonin affects Cd accumulation and rice quality, a series of experiments were conducted. The results showed that exogenous melatonin application was associated with reduced Cd accumulation (23–43%) in brown rice. Fourier transform infrared spectroscopy (FTIR) analysis showed that exogenous melatonin affected the rice protein secondary structure and starch short-range structure. Metabolomics based on LC–MS/MS revealed that exogenous melatonin altered the brown rice metabolic profile, decreased fatty acid metabolite content, but increased amino acid metabolite, citric acid, melatonin biosynthetic metabolite, and plant hormone contents. These findings indicate that exogenous melatonin can effectively reduced Cd accumulation and improve rice quality through metabolic network regulation, serving as an effective treatment for rice cultivated in Cd-contaminated soil.

Spore Germination of Diplazium simplicivenium Holtt. (Athyriaceae) in Peninsular Malaysia

Diplazium simplicivenium Holtt. a species of fern in Peninsular Malaysia. This study reports an efficient method for D. simplicivenium spore sterilisation and the effect of plant growth regulators (PGRs) via green globular bodies (GGB). Sterilisation with 0.1% mercuric chloride effectively allowed spore germination. The result showed that the culture media supplemented with 0.5 mg/L gibberellin positively affects the weight of GGB and the number of shoots with significant differences (ANOVA, p < 0.05). The soaking technique established in this study for spore sterilisation is an efficient approach, and the optimal plant and concentration of plant hormones were identified. This procedure can be applied to other indigenous ferns and closely similar species.

Comparative transcriptome revealed the molecular responses of Aconitum carmichaelii Debx. to downy mildew at different stages of disease development

BackgroundAconitum carmichaelii Debx. has been widely used as a traditional medicinal herb for a long history in China. It is highly susceptible to various dangerous diseases during the cultivation process. Downy mildew is the most serious leaf disease of A. carmichaelii, affecting plant growth and ultimately leading to a reduction in yield. To better understand the response mechanism of A. carmichaelii leaves subjected to downy mildew, the contents of endogenous plant hormones as well as transcriptome sequencing were analyzed at five different infected stages.ResultsThe content of 3-indoleacetic acid, abscisic acid, salicylic acid and jasmonic acid has changed significantly in A. carmichaelii leaves with the development of downy mildew, and related synthetic genes such as 9-cis-epoxycarotenoid dioxygenase and phenylalanine ammonia lyase were also significant for disease responses. The transcriptomic data indicated that the differentially expressed genes were primarily associated with plant hormone signal transduction, plant-pathogen interaction, the mitogen-activated protein kinase signaling pathway in plants, and phenylpropanoid biosynthesis. Many of these genes also showed potential functions for resisting downy mildew. Through weighted gene co-expression network analysis, the hub genes and genes that have high connectivity to them were identified, which could participate in plant immune responses.ConclusionsIn this study, we elucidated the response and potential genes of A. carmichaelii to downy mildew, and observed the changes of endogenous hormones content at different infection stages, so as to contribute to the further screening and identification of genes involved in the defense of downy mildew.

Plant hormone profiling of scion and rootstock incision sites and intra- and inter-family graft junctions in Nicotiana benthamiana

ABSTRACT Many previous studies have suggested that various plant hormones play essential roles in the grafting process. In this study, to understand the plant hormones that accumulate in the graft junctions, whether these are supplied from the scion or rootstock, and how these hormones play a role in the grafting process, we performed a hormonome analysis that accumulated in the incision site of the upper plants from the incision as “ungrafted scion” and lower plants from the incision as “ungrafted rootstock” in Nicotiana benthamiana. The results revealed that indole-3-acetic acid (IAA) and gibberellic acid (GA), which regulate cell division; abscisic acid (ABA) and jasmonic acid (JA), which regulate xylem formation; cytokinin (CK), which regulates callus formation, show different accumulation patterns in the incision sites of the ungrafted scion and rootstock. In addition, to try discussing the differences in the degree and speed of each event during the grafting process between intra- and inter-family grafting by determining the concentration and accumulation timing of plant hormones in the graft junctions, we performed hormonome analysis of graft junctions of intra-family grafted plants with N. benthamiana as scion and Solanum lycopersicum as rootstock (Nb/Sl) and inter-family grafted plants with N. benthamiana as scion and Arabidopsis thaliana as rootstock (Nb/At), using the ability of Nicotiana species to graft with many plant species. The results revealed that ABA and CK showed different accumulation timings; IAA, JA, and salicylic acid (SA) showed similar accumulation timings, while different accumulated concentrations in the graft junctions of Nb/Sl and Nb/At. This information is important for understanding the molecular mechanisms of plant hormones in the grafting process and the differences in molecular mechanisms between intra- and inter-family grafting.

Occurrence of plant hormones in composts made from organic fraction of agri-food industry waste

Utilizing the organic fraction of agri-food industry waste for fertilization represents one approach to waste management, with composting emerging as a popular method. Composts derived from this waste may contain plant hormones alongside primary macronutrients. This study aimed to evaluate the content of plant hormones in composts crafted from the organic fraction of agri-food industry waste. The presence of these substances was ascertained using liquid chromatography–mass spectrometry (LC-MS) analysis, applied to extracted samples from three composts produced in a bioreactor and three obtained from companies. The results indicate the presence of 35 compounds, which belong to six types of plant hormones: auxins, cytokinins, gibberellins, brassinosteroids, abscisic acid, and salicylic acid, in composts for the first time. The highest amount of plant hormones was noted in buckwheat husk and biohumus extract (35 compounds), and the lowest in hemp chaff and apple pomace (14 compounds). Brassinosteroids (e.g., brassinolide, 28-homobrassinolide, 24-epicastasterone, 24-epibrassinolide, and 28-norbrassinolide) and auxins (e.g., indolilo-3-acetic acid) are dominant. The highest concentration of total phytohormones was reported in biohumus extract (2026.42 ng g−1 dry weight), and the lowest in organic compost (0.18 ng g−1 dry weight).

Silencing of early auxin responsive genes MdGH3-2/12 reduces the resistance to Fusarium solani in apple

Apple replant disease (ARD) has led to severe yield and quality reduction in the apple industry. Fusarium solani (F. solani) has been identified as one of the main microbial pathogens responsible for ARD. Auxin (indole-3-acetic acid, IAA), an endogenous hormone in plants, is involved in almost all plant growth and development processes and plays a role in plant immunity against pathogens. Gretchen Hagen3 (GH3) is one of the early/primary auxin response genes. The aim of this study was to evaluate the function of MdGH3-2 and MdGH3-12 in the defense response of F. solani by treating MdGH3-2/12 RNAi plants with F. solani. The results show that under F. solani infection, RNAi of MdGH3-2/12 inhibited plant biomass accumulation and exacerbated root damage. After inoculation with F. solani, MdGH3-2/12 RNAi inhibited the biosynthesis of acid-amido synthetase. This led to the inhibition of free IAA combining with amino acids, resulting in excessive free IAA accumulation. This excessive free IAA altered plant tissue structure, accelerated fungal hyphal invasion, reduced the activity of antioxidant enzymes (SOD, POD and CAT), increased the reactive oxygen species (ROS) level, and reduced total chlorophyll content and photosynthetic ability, while regulating the expression of PR-related genes including PR1, PR4, PR5 and PR8. It also changed the contents of plant hormones and amino acids, and ultimately reduced the resistance to F. solani. In conclusion, these results demonstrate that MdGH3-2 and MdGH3-12 play an important role in apple tolerance to F. solani and ARD.

Tamyb10-D1 restores red grain color and increases grain dormancy via suppressing expression of TaLTP2.128, non-specific lipid transfer protein in wheat

Grain dormancy of wheat is closely associated with grain color: red-grained lines show higher dormancy than white-grained lines. The production of red pigments is regulated by R-1, Tamyb10 gene. However, the relation between grain color and dormancy remains unknown. For this study, we generated transgenic lines which were introduced a DNA fragment containing Tamyb10-D1 gene and its a 2 kb promoter including the 5′ untranslated region into white-grained wheat. Transgenic lines showed red-grained and higher dormant traits. Contents of plant hormones and gene expression of embryos at 30 days after pollination were examined in a wild type and a transgenic line. No differences were observed in the contents of plant hormones, but several genes are differentially expressed between these lines. One differentially expressed gene, TaLTP2.128, is a member of non-specific lipid transfer proteins. It was expressed higher in white grains than in red grains. A putative amino acid sequence showed similarity to that of OsHyPRP5, which is identified as QTL controlling low-temperature germinability in rice. Expression of TaLTP2.128 was increased by grain imbibition. The increasing levels were higher not only in other white-grained lines, but also in non-dormant red-grained lines. TaLTP2.128 was expressed at a quite early stage of germination. These study findings indicate that Tamyb10 regulates dormancy release by the modification of TaLTP2.128 acting as trigger of germination.

Attenuated total reflection Fourier-transform infrared spectroscopy for the prediction of hormone concentrations in plants.

Plant hormones are important in the control of physiological and developmental processes including seed germination, senescence, flowering, stomatal aperture, and ultimately the overall growth and yield of plants. Many currently available methods to quantify such growth regulators quickly and accurately require extensive sample purification using complex analytic techniques. Herein we used ultra-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) to create and validate the prediction of hormone concentrations made using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectral profiles of both freeze-dried ground leaf tissue and extracted xylem sap of Japanese knotweed (Reynoutria japonica) plants grown under different environmental conditions. In addition to these predictions made with partial least squares regression, further analysis of spectral data was performed using chemometric techniques, including principal component analysis, linear discriminant analysis, and support vector machines (SVM). Plants grown in different environments had sufficiently different biochemical profiles, including plant hormonal compounds, to allow successful differentiation by ATR-FTIR spectroscopy coupled with SVM. ATR-FTIR spectral biomarkers highlighted a range of biomolecules responsible for the differing spectral signatures between growth environments, such as triacylglycerol, proteins and amino acids, tannins, pectin, polysaccharides such as starch and cellulose, DNA and RNA. Using partial least squares regression, we show the potential for accurate prediction of plant hormone concentrations from ATR-FTIR spectral profiles, calibrated with hormonal data quantified by UHPLC-HRMS. The application of ATR-FTIR spectroscopy and chemometrics offers accurate prediction of hormone concentrations in plant samples, with advantages over existing approaches.

Transcriptomics reveals a core transcriptional network of K-type cytoplasmic male sterility microspore abortion in wheat (Triticum aestivum L.)

BackgroundCytoplasmic male sterility (CMS) plays a crucial role in hybrid production. K-type CMS, a cytoplasmic male sterile line of wheat with the cytoplasms of Aegilops kotschyi, is widely used due to its excellent characteristics of agronomic performance, easy maintenance and easy restoration. However, the mechanism of its pollen abortion is not yet clear.ResultsIn this study, wheat K-type CMS MS(KOTS)-90-110 (MS line) and it’s fertile near-isogenic line MR (KOTS)-90-110 (MR line) were investigated. Cytological analysis indicated that the anthers of MS line microspore nucleus failed to divide normally into two sperm nucleus and lacked starch in mature pollen grains, and the key abortive period was the uninucleate stage to dinuclear stage. Then, we compared the transcriptome of MS line and MR line anthers at these two stages. 11,360 and 5182 differentially expressed genes (DEGs) were identified between the MS and MR lines in the early uninucleate and binucleate stages, respectively. Based on GO enrichment and KEGG pathways analysis, it was evident that significant transcriptomic differences were “plant hormone signal transduction”, “MAPK signaling pathway” and “spliceosome”. We identified 17 and 10 DEGs associated with the IAA and ABA signal transduction pathways, respectively. DEGs related to IAA signal transduction pathway were downregulated in the early uninucleate stage of MS line. The expression level of DEGs related to ABA pathway was significantly upregulated in MS line at the binucleate stage compared to MR line. The determination of plant hormone content and qRT-PCR further confirmed that hormone imbalance in MS lines. Meanwhile, 1 and 2 DEGs involved in ABA and Ethylene metabolism were also identified in the MAPK cascade pathway, respectively; the significant up regulation of spliceosome related genes in MS line may be another important factor leading to pollen abortion.ConclusionsWe proposed a transcriptome-mediated pollen abortion network for K-type CMS in wheat. The main idea is hormone imbalance may be the primary factor, MAPK cascade pathway and alternative splicing (AS) may also play important regulatory roles in this process. These findings provided intriguing insights for the molecular mechanism of microspore abortion in K-type CMS, and also give useful clues to identify the crucial genes of CMS in wheat.

Silicon application enhances wheat defence against Sitobion avenae F. by regulating plant physiological-biochemical responses

Sitobion avenae F. is a highly prevalent and devastating pest in wheat crops, leading to significant yield losses. Silicon (Si) has been widely recognized as an effective inducer of plant resistance against aphids. Nevertheless, the underlying mechanisms governing the physiological and biochemical responses of plants induced by Si defense against S. avenae F. remain incompletely understood. In this study, we conducted experiments by treating wheat leaves with varying concentrations of Tetraethyl orthosilicate (TEOS) spray under aphid infestation. We meticulously observed and recorded the life cycle of S. avenae F. and measured the content of plant hormones, secondary metabolites, and the activity of defense enzymes in wheat leaves. Furthermore, we utilized structural equation modeling to discern the causal correlation between aphid performance and the physiological-biochemical responses of wheat under TEOS sprays. Our findings revealed that a concentration of 3 mmol/L TEOS significantly shortened the net reproductive rate, intrinsic rate and finite rate of increase, and mean generation time of S. avenae F., while simultaneously prolonging the population doubling time. Additionally, the content of lignin, total phenolics, flavonoids, alkaloids, tannin, jasmonic acid (JA), and salicylic acid in wheat leaves exhibited a substantial increase. Furthermore, the activity of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), catalase, and lipoxygenase in wheat leaves was significantly enhanced. Our results suggest that TEOS spray reduced the survival and population growth of S. avenae F. while enhancing the defense response of wheat against aphids by activating the activity of PAL and PPO in wheat, and increasing the content of total phenolic and JA. This work provides valuable insights for the development of appropriate Si fertilizers for effective pest management and offers robust theoretical support for wheat aphid control through agricultural fertilization strategies.