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In this study, Bi2O3 nanoparticles are prepared via an impregnation method and modified using multi-walled carbon nanotubes (MWCNTs) and PW12. XRD reveals that the prepared Bi2O3 corresponded to the monoclinic α-phase. SEM results reveal that the composite consists of a series of nanosheets with flower-like structures. In this study, malachite green (MG) is used as a simulated contaminant to test the degradation capability of the compound under sunlight, and the effect of PW12 doping on the photocatalytic properties of the sample is investigated. The results show that the degradation kinetic constant of 0.3 PW12/MWCNTs/Bi2O3 (0.8125 h−1) is about 3 times that of Bi2O3 (0.2767 h−1). The ternary complex containing 30% PW12 has a degradation rate of 95% in 2.5 h. h+ and · O 2 - were the major active species in the photocatalytic degradation of MG. [ABSTRACT FROM AUTHOR]

An increasing number of biosensor design strategies have emerged in recent years, capable of providing potential practical applications for point-of-care testing (POCT) in various human diseases. Compared to conventional biosensors, the latest POCT assays research aims at improving sensor precision, cost-effectiveness and time-consumption. Here，an electrochemiluminescence biosensor and colorimetric method is emerged for rapid, accurate and sensitive determination of biomarker microRNA-141. The target firstly opens the hairpins formed by Ag(I) that acting as a bridge between two cytosine, and the released Ag(I) is selectively recognized by CdTe quantum dots resulting in a decrease in electrochemiluminescence signal and a color change in solution as a visual signal. Then, the introduction of assistant DNA triggers a subsequent catalytic hairpin assembly reaction (CHA), allowing the target to be continuously cycled and further scaled up. The emerging sensor has the advantages of simple, fast (the whole detection process takes about 4 h，takes less time than other biosensors), high sensitivity, good selectivity, and wide linear range (100 aM to 100 pM, with a low LOD as 41.6 aM for electrochemiluminescence and 123.8 aM for colorimetric, respectively), eliminating probe labeling and analysis strategies, which greatly improves the practicality of the method and is expected to realize low-cost and high-sensitivity POCT of microRNAs. • An HO-ECL/colorimetric dual-readout biosensor is developed for microRNA based on CRR cascade CHA. • Dual signal readout and POCT applications are achieved based on only one luminescent emitter. • The proposed biosensor shows a high reliability and sensitivity with a faster, cheaper, and better detection method. [ABSTRACT FROM AUTHOR]

Coronatine (COR) is a phytotoxin produced by Pseudomonas syringae . Its structure is similar to those of jasmonates (JAs), which play diverse roles in multiple plant biotic and abiotic defenses. However, the biological activity of COR is 1000 times greater than the activity of JA. In addition to being involved in the JA pathway, COR affects plant photosynthetic efficiency. In this study, we examined wheat blade pretreatment with COR. Blades treated with COR remained green longer than those of control plants under drought stress conditions, resulting in less yield loss with COR treatment. To investigate the mechanism of COR in drought resistance further, we employed two-dimensional gel electrophoresis technology and matrix-assisted laser desorption/ionization mass spectrometry to sequester and identify key proteins. Six COR-inducible proteins that are located in the chloroplast and involved directly in photosynthesis were found. The wheat homologue of protein gi|326509937 is degradation of periplasmic proteins 1 (DEGP1) in Arabidopsis , which is a response to photosystem II reparation, and was maintained at a low level with COR treatment. Finally, we measured levels of chlorophyll and photosynthetic performance to reveal the phenotypic effect of COR. Taken together, the results demonstrate that COR enhances drought tolerance by maintaining high photosynthetic performance. [ABSTRACT FROM AUTHOR]

Egg yolk-derived phosvitin phosphopeptides (PPPs) are considered to have a huge potential in nutraceutical and cosmetic industries for their high Ca2+ binding capacity and antioxidant activity. This work aimed to obtain information on effect of fertilization on conformation of phosvitin (PSV) and bioactivities of PPPs. After 12days of incubation, a significant decrease was seen in phosphorus content of PSV. The conformational and thermal analyses indicated that PSV underwent a conformational change during incubation, and the PSV on day 12 possessed a much more unfolded structure. Correspondingly, the PPPs derived from fertilized egg PSV exhibited stronger Ca2+ binding capacity (18.4ppm at 600mg/L) and antioxidant activities against DPPH radical, hydroxyl radical and lipid peroxidation than that of PPPs from unfertilized egg PSV. These results suggested that fertilized egg could be explored as a potential source of bioactive phosphopeptides. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) originate from primary transcripts (pri-miRNAs) with characteristic stem-loop structures, and their accurate processing is required for the production of functional miRNAs. Here, using the pri-miR-166 family in Arabidopsis thaliana as a paradigm, we report the crucial role of pri-miRNA terminal loops in miRNA biogenesis. We found that multibranched terminal loops in pri-miR-166s substantially suppress miR-166 expression in vivo. Unlike canonical processing of pri-miRNAs, terminal loop-branched pri-miRNAs can be processed by Dicer-like 1 (DCL1) complexes bidirectionally from base to loop and from loop to base, resulting in productive and abortive processing of miRNAs, respectively. In both cases, DCL1 complexes canonically cut pri-miRNAs at a distance of 16-17 bp from a reference single-stranded loop region. DCL1 also adjusts processing sites toward an internal loop through its helicase domain. These results provide new insight into the poorly understood processing mechanism of pri-miRNAs with complex secondary structures. [ABSTRACT FROM AUTHOR]

Abstract: Silicon (Si) may be involved in metabolic, physiological, and/or structural activity in higher plants exposed to abiotic and biotic stresses. This has not yet been determined due to the absence of direct evidence that it is part of the molecule of an essential plant constituent or metabolite. The aim of this study was to investigate the effect of silicon on soybean seedlings under drought and ultraviolet-B (UV-B) radiation stresses. The relative leaf water content (RWC), which was the main factor resulting in reduced growth in response to drought, increased 19.0% and 30.0% with Si application under drought and drought+UV-B stresses, respectively. Under UV-B radiation, the anthocyanin and phenol levels decreased 91.5% and 10.0% in the treatment of Si. Ultraviolet-B radiation and drought stress caused great membrane damage, as assessed by lipid peroxidation and osmolyte leakage, but Si application significantly reduced the membrane damage. Catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and hydrogen peroxide were observed under stress conditions. Proline increased primarily in drought-stressed seedlings and may be the drought-induced factor with a protective role in response to UV-B and silicon. Photosynthesis (P N) increased following Si application by 21.0%, 18.3% and 21.5% under UV-B radiation, drought and the combination, respectively. The physiological and biochemical parameters measured indicated that the UV-B light had more adverse effects on growth of soybean seedlings than drought, but the data also showed that Si could alleviate seedling damage under these stress conditions. [ABSTRACT FROM AUTHOR]

A novel electromagnetic heat extraction method was presented, whereby mandarin peels residue solution was located in a winding coil subjected to an oscillating magnetic field, and the pectin was extracted under appropriate conditions. Numerical relationships between applied magnetic field and induced electric field (IEF) in the extraction process were elaborated. The results showed that the induced current density, IEF and terminal temperature increased with increasing magnetic field. The maximum current density of 0.35 A/cm corresponds to the highest terminal temperature of 84.6 °C and IEF intensity of 26.6 V/cm. When magnetic field intensity was 1.39 T and the extraction time was 15 min, the maximum yield of pectin reached 9.16 %. In addition, all treatments impacted the ash content, protein content, water-holding capacity (WHC), and oil-holding capacity (OHC) of the obtained pectin. The pectin extracted by electromagnetic heat had the lowest DE value of 71.3 % with 126.55 kDa molecular weight, while the GalA content was at the highest level of 76.18 %. After different treatments, the composition of pectin monosaccharides changed, but there were slight differences in the composition of pectin polysaccharides. Moreover, the electromagnetic heat extracted pectin had light color and an obvious surface fragmentation of the peel residue. [Display omitted] • Novel electromagnetic heat method was presented for the extraction of pectin. • The maximum yield of pectin reached 9.16 % at 1.39 T and 15 min. • Electromagnetic heat extracted pectin had brighter color and highest GalA level. • There were slight differences in the composition of polysaccharides. [ABSTRACT FROM AUTHOR]

[Display omitted] The photoreduction of the green-house gas CO 2 into carbon monoxide (CO) is a growing process due to the use of CO for the production of methanol in the Fischer-Tropsch process and the synthesis of many of the bulk chemicals. Here, we have synthesized phosphorous doped graphitic carbon nitride (P-g-C 3 N 4) sensitized by the cobalt phthalocyanine complex for the molecular reduction of CO 2 into CO under visible-light irradiation—the doping of phosphorous improved the stability as well as the harvesting of the visible region. The CoPc@P-g-C 3 N 4 hybrid photocatalyst exhibited the highest efficiency for the photoreduction of CO 2 with a high yield of 295 μmol-g−1 for CO under the experimental conditions. Also, hydrogen with low concentration was identified as a by-product under the experimental conditions. The photocatalyst had stability for six consecutive runs with negligible loss of the activity and no leaching of the cobalt content at the end of the sixth run of the photoreduction experiment. The stability of the photocatalysts is an advantage, which made it a suitable candidate for the current reaction system. [ABSTRACT FROM AUTHOR]

Summary: Stomatal density (SD) is closely related to crop drought resistance. Understanding the genetic basis for natural variation in SD may facilitate efforts to improve water‐use efficiency. Here, we report a genome‐wide association study for SD in maize seedlings, which identified 18 genetic variants that could be resolved to seven candidate genes. A 3‐bp insertion variant (InDel1089) in the last exon of Zea mays (Zm) IRX15A (Irregular xylem 15A) had the most significant association with SD and modulated the translation of ZmIRX15A mRNA by affecting its secondary structure. Dysfunction of ZmIRX15A increased SD, leading to an increase in the transpiration rate and CO2 assimilation efficiency. ZmIRX15A encodes a xylan deposition enzyme and its disruption significantly decreased xylan abundance in secondary cell wall composition. Transcriptome analysis revealed a substantial alteration of the expression of genes involved in stomatal complex morphogenesis and drought response in the loss‐of‐function of ZmIRX15A mutant. Overall, our study provides important genetic insights into the natural variation of leaf SD in maize, and the identified loci or genes can serve as direct targets for enhancing drought resistance in molecular‐assisted maize breeding. [ABSTRACT FROM AUTHOR]

The lengths of the basal internodes is an important factor for lodging resistance of maize (Zea mays). In this study, foliar application of coronatine (COR) to 10 cultivars at the V8 growth stage had different suppression effects on the length of the eighth internode, with three being categorized as strong-inhibition cultivars (SC), five as moderate (MC), and two as weak (WC). RNA-sequencing of the eighth internode of the cultivars revealed a total of 7895 internode elongation-regulating genes, including 777 transcription factors (TFs). Genes related to the hormones cytokinin, gibberellin, auxin, and ethylene in the SC group were significantly down-regulated compared to WC, and more cell-cycle regulatory factors and cell wall-related genes showed significant changes, which severely inhibited internode elongation. In addition, we used EMSAs to explore the direct regulatory relationship between two important TFs, ZmABI7 and ZmMYB117, which regulate the cell cycle and cell wall modification by directly binding to the promoters of their target genes ZmCYC1 , ZmCYC3 , ZmCYC7 , and ZmCPP1. The transcriptome reported in this study will provide a useful resource for studying maize internode development, with potential use for targeted genetic control of internode length to improve the lodging resistance of maize. [ABSTRACT FROM AUTHOR]

Coronatine (COR) is a phytotoxin produced by Pseudomonas syringae. Its structure is similar to Jasmonates, which play a number of diverse roles in plant defense. Both have the COI1 plant receptor, so coronatine can manipulate plant hormone signaling to access nutrients and counteract defense responses. In addition to the hormone system, coronatine affects plant nitrogenous metabolism and chloroplast ultrastructure. In this study, we first examined a typical nitrogen-losing phenotype, and used the polyacrylamide gel approach to demonstrate soluble total protein patterns in a time-course experiment under different temperature conditions. We then employed dimensional gel electrophoresis technology (2-DE) and MALDI-TOF-MS to sequester and identify the sensitive proteins. We found a total of 27 coronatine sensitive proteins, 22 of which were located in the chloroplast and 6 of which were directly involved in photosynthesis. Finally, we measured levels of chlorophyll and photosynthetic performance to reveal the phenotypic effect of these proteins. Taken together, these results demonstrated that coronatine enhanced heat tolerance by regulating nitrogenous metabolism and chloroplast ultrastructure to maintain photosynthetic performance and reduce yield loss under heat stress. [ABSTRACT FROM AUTHOR]

Strigolactones (SLs) are a class of plant hormones and rhizosphere communication signals of great interest. They perform diverse biological functions including the stimulation of parasitic seed germination and phytohormonal activity. However, their practical use is limited by their low abundance and complex structure, which requires simpler SL analogues and mimics with maintained biological function. Here, new, hybrid-type SL mimics were designed, derived from Cinnamic amide, a new potential plant growth regulator with good germination and rooting-promoting activities. Bioassay results indicated that compound 6 not only displayed good germination activity against the parasitic weed O. aegyptiaca with an EC50 value of 2.36 × 10−8 M, but also exhibited significant inhibitory activity against Arabidopsis root growth and lateral root formation, as well as promoting root hair elongation, similar to the action of GR24. Further morphological experiments on Arabidopsis max2-1 mutants revealed that 6 possessed SL-like physiological functions. Furthermore, molecular docking studies indicated that the binding mode of 6 was similar to that of GR24 in the active site of OsD14. This work provides valuable clues for the discovery of novel SL mimics. [ABSTRACT FROM AUTHOR]

Aims: In this study, a novel plant growth regulator 2,4-dichloroformamide cyclopropane acid (B2) was used to explore its effects on wheat stalk morphology, chemical composition, anatomical structure, crushing strength and their relationship with lodging resistance. The effects of stem quality change on grain filling and yield were further discussed. Methods: We conducted a series of experiments, including determinations of internode morphology and breaking resistance, analyses of chemical composition and hormone content, observation of internode anatomy, and measurement of grain filling rate, to explore the effects of internode developmental changes induced by B2 treatment on grain filling. Results: Spraying 150 μmol·L−1 B2 at jointing stage significantly decreased plant height, height of center of gravity, basal internode and cell length, while increased stem diameter, wall thickness of basal second internode, cortex thickness, vascular bundle transverse section area and cell cross-sectional area, which resulted in higher breaking strength and culm lodging resistance index. B2 also significantly reduced the content of gibberellin in the second basal internode, and increased the accumulation of lignin and cellulose, thus forming a shorter and stronger stalk. Correlation analysis showed that stem outer diameter, stem wall thickness, cellulose and lignin content were significantly and positively correlated with stem breaking strength. The improvement of stalk structure, especially vascular bundle area, increased bleeding sap, which contributed to grain filling and final yield formation. Conclusions: Lodging resistance and average grain-filling rate can be enhanced by spraying B2 at wheat jointing stage due to the improvement of culm structure, which is conducive to further increase of yield. [ABSTRACT FROM AUTHOR]

Graphdiyne oxide quantum dots (GDYO QDs), as derivatives of graphdiyne (GDY), have excellent electroconductibility and luminous properties and can be applied as a new ECL emitter. Herein, an electrochemiluminescence (ECL) biosensor for miRNA-21 ultrasensitive determination is constructed based on AuNPs/GDY, GDYO QD and oligonucleotide signal amplification strategy that integrates DNA walker and hybridization chain reaction (HCR) amplification. As electrode substrate material, AuNPs/GDY can not only bond with the aptamer CP but can also enhance the conductivity of the interface. When miRNA-21 exists, the DNA walker process is initiated, and the signaling probes are introduced on the electrode surface, producing abundant double-stranded H1/H2; then, H3/H4 undergoes complementary base pairing with H1/H2 through HCR. With the increase in miRNA-21, the 3D DNA nanomachine is actively manipulated, resulting in a gradual increase in ECL signal. This ECL biosensor demonstrates outstanding performance in the determination of miRNA-21 in the linear range from 0.1 fM to 1 nM. This study offers a new sensitive idea for the clinical analysis of cancer biomarkers. [ABSTRACT FROM AUTHOR]

Exploring new highly efficient electrochemiluminescence (ECL) luminophores is a necessary condition for developing ultrasensitive ECL biosensors. Therefore, a luminescent carbon dot-based covalent organic framework (CD-COF) was prepared using aldehyde-based carbon dots (CDs) and 1,3,5-tris (4-aminophenyl) benzene (TPB). Because the CD-COF made the regular arrangement of CDs conducive to improving the ECL response, CD-COF had a higher ECL intensity and efficiency than CDs. What's more, the ECL intensity of the CD-COF/S2O82−/Bu4N+ system was about 2.98, 7.50, and 28.08 times higher than those of the CD-COF/S2O82−, CDs/S2O82− and S2O82− systems, respectively. Considering the remarkable ECL performance, the CD-COF/S2O82−/Bu4N+ system was employed combined with the CRISPR/Cas12a trans-cutting strategy to construct an "off–on" ECL biosensor for BPA detection. The proposed ECL biosensor exhibited excellent performance with a wide linear range from 1.0 × 10−14 mol L−1 to 1.0 × 10−5 mol L−1 with a low detection limit of 2.21 fM (S/N = 3) under the optimized conditions. The biosensor demonstrated that CD-COF can be used as an efficient ECL emitter, thus expanding the application field of COFs. In addition, the good stability and specificity of the biosensor enabled the rapid detection of BPA, which will provide valuable insights into promising ultrasensitive ECL biosensors. [ABSTRACT FROM AUTHOR]

Water uptake is crucial for crop growth and development and drought stress tolerance. The water channel aquaporins (AQP) play important roles in plant water uptake. Here, we discovered that a jasmonic acid analog, coronatine (COR), enhanced maize (Zea mays) root water uptake capacity under artificial water deficiency conditions. COR treatment induced the expression of the AQP gene Plasma membrane intrinsic protein 2;5 (ZmPIP2;5). In vivo and in vitro experiments indicated that COR also directly acts on ZmPIP2;5 to improve water uptake in maize and Xenopus oocytes. The leaf water potential and hydraulic conductivity of roots growing under hyperosmotic conditions were higher in ZmPIP2;5‐overexpression lines and lower in the zmpip2;5 knockout mutant, compared to wild‐type plants. Based on a comparison between ZmPIP2;5 and other PIP2s, we predicted that COR may bind to the functional site in loop E of ZmPIP2;5. We confirmed this prediction by surface plasmon resonance technology and a microscale thermophoresis assay, and showed that deleting the binding motif greatly reduced COR binding. We identified the N241 residue as the COR‐specific binding site, which may activate the channel of the AQP tetramer and increase water transport activity, which may facilitate water uptake under hyperosmotic stress. [ABSTRACT FROM AUTHOR]

Graphdiyne (GDY) is an sp and sp2 co-hydrocarbon allotrope whose particular structure endows it with many fascinating properties, including abundant chemical bonds, high conjugation, natural pores, high carrier mobility, high conductivity and stability, etc. In this work, two-dimensional graphdiyne is prepared as an electrode substrate material coupling with an exonuclease III-assisted amplification strategy to construct a superior-performance self-powered biosensor based on enzymatic biofuel cells for highly sensitive detection of the tumour marker miRNA-21. Glucose oxidase (GOD) is first immobilized on the GDY/AuNP composite to prepare a bioconjugate. GDY/AuNP modified carbon cloth is used as an enzyme biofuel cell electrode, which is then modified with bilirubin oxidase as a biocathode. The bioconjugate binds to GOD through specific binding to the bioanode. When miRNA-21 is present, specific recognition by exonuclease III in the system results in cleavage of the capture probe, and miRNA-21 is recovered and involved in the cycle. The target miRNA-21 then causes corresponding changes in the open-circuit voltage of the self-powered system. Based on this, a sensitive detection method was constructed, within the scope from 0.1 fM to 0.1 nM with a shallow detection limit of 55.2 aM (S/N = 3). The new approach triumphantly has been used to detect miRNA-21 in serum, which provides a compelling new way for early diagnosis of related cancers. [ABSTRACT FROM AUTHOR]

Background: Low grain water content (GWC) at harvest of maize (Zea mays L.) is essential for mechanical harvesting, transportation and storage. Grain drying rate (GDR) is a key determinant of GWC. Many quantitative trait locus (QTLs) related to GDR and GWC have been reported, however, the confidence interval (CI) of these QTLs are too large and few QTLs has been fine-mapped or even been cloned. Meta-QTL (MQTL) analysis is an effective method to integrate QTLs information in independent populations, which helps to understand the genetic structure of quantitative traits. Results: In this study, MQTL analysis was performed using 282 QTLs from 25 experiments related GDR and GWC. Totally, 11 and 34 MQTLs were found to be associated with GDR and GWC, respectively. The average CI of GDR and GWC MQTLs was 24.44 and 22.13 cM which reduced the 57 and 65% compared to the average QTL interval for initial GDR and GWC QTL, respectively. Finally, 1494 and 5011 candidate genes related to GDR and GWC were identified in MQTL intervals, respectively. Among these genes, there are 48 genes related to hormone metabolism. Conclusions: Our studies combined traditional QTL analyses, genome-wide association study and RNA-seq to analysis major locus for regulating GWC in maize. [ABSTRACT FROM AUTHOR]

Background: MicroRNA (miRNA) plays vital roles in the regulation of both plant architecture and stress resistance through cleavage or translation inhibition of the target messenger RNAs (mRNAs). However, miRNA-induced gene silencing remains a major challenge in vivo due to the low delivery efficiency and instability of miRNA, thus an efficient and simple method is urgently needed for miRNA transformation. Previous researches have constructed a star polycation (SPc)-mediated transdermal double-stranded RNA (dsRNA) delivery system, achieving efficient dsRNA delivery and gene silencing in insect pests. Results: Here, we tested SPc-based platform for direct delivery of double-stranded precursor miRNA (ds-MIRNA) into protoplasts and plants. The results showed that SPc could assemble with ds-MIRNA through electrostatic interaction to form nano-sized ds-MIRNA/SPc complex. The complex could penetrate the root cortex and be systematically transported through the vascular tissue in seedlings of Arabidopsis and maize. Meanwhile, the complex could up-regulate the expression of endocytosis-related genes in both protoplasts and plants to promote the cellular uptake. Furthermore, the SPc-delivered ds-MIRNA could efficiently increase mature miRNA amount to suppress the target gene expression, and the similar phenotypes of Arabidopsis and maize were observed compared to the transgenic plants overexpressing miRNA. Conclusion: To our knowledge, we report the first construction and application of star polycation nanocarrier-based platform for miRNA delivery in plants, which explores a new enable approach of plant biotechnology with efficient transformation for agricultural application. [ABSTRACT FROM AUTHOR]

A mild and efficient method for the cobalt-catalyzed hydroxyperfluoroalkylation of alkenes has been developed. This method demonstrated broad substrate scope, good yields, and mild conditions with the tolerance of mono-, di-, and trisubstituted alkenes including both styrenes and non-activated aliphatic olefins. This strategy offered a valuable solution for rapid and efficient construction of β-perfluoro-alkyl alcohols using widely available and inexpensive perfluoroalkyl bromides- and atmospheric oxygen. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effect of induced electric field (IEF) treatment on acid hydrolysis of corn starch by altering the connection modes of sample coils of a 4-reactor IEF system. Results suggested that IEF treatment could enhance the hydrolysis of corn starch and series connection (1. RRRR, η = 16 E Si 2 P in 4 Z Si + Z load ) exhibited higher energy efficiency than parallel (9. (RRRR), η = 4 E Si 2 P in Z Si + 4 Z load ), thus contributing to more extensive hydrolysis. Although no new functional group was formed, the starch granules were partially cracked into pieces and the crystallinity was slightly increased after IEF-assisted hydrolysis. Differential scanning calorimetry results indicated that IEF-assisted hydrolysis increased the gelatinization temperatures but decreased the enthalpy of starch, with a greatest variation was observed by series connection. Rapid visco-analysis showed that IEF-assisted hydrolysis greatly decreased the pasting viscosity of corn starch and also series connection showed the strongest reduction. The obtained results could provide a theoretical guide for the applications of IEF technology in biomaterial processing. [Display omitted] • Induced electric field (IEF) could enhance the acid hydrolysis of corn starch. • IEF-assisted hydrolysis highly depends on the energy efficiency of IEF system. • Series connection of IEF reactors showed the highest energy efficiency. • IEF-assisted hydrolysis largely decreased the pasting viscosity of corn starch. • IEF-assisted hydrolysis increased gelatinization temperatures but decreased enthalpy. [ABSTRACT FROM AUTHOR]

Background: Lodging is one of the important factors causing maize yield. Plant height is an important factor in determining plant architecture in maize (Zea mays L.), which is closely related to lodging resistance under high planting density. Coronatine (COR), which is a phytotoxin and produced by the pathogen Pseudomonas syringae, is a functional and structural analogue of jasmonic acid (JA). Results: In this study, we found COR, as a new plant growth regulator, could effectively reduce plant height and ear height of both hybrids (ZD958 and XY335) and inbred (B73) maize by inhibiting internode growth during elongation, thus improve maize lodging resistance. To study gene expression changes in internode after COR treatment, we collected spatio-temporal transcriptome of inbred B73 internode under normal condition and COR treatment, including the three different regions of internode (fixed, meristem and elongation regions) at three different developmental stages. The gene expression levels of the three regions at normal condition were described and then compared with that upon COR treatment. In total, 8605 COR-responsive genes (COR-RGs) were found, consist of 802 genes specifically expressed in internode. For these COR-RGs, 614, 870, 2123 of which showed expression changes in only fixed, meristem and elongation region, respectively. Both the number and function were significantly changed for COR-RGs identified in different regions, indicating genes with different functions were regulated at the three regions. Besides, we found more than 80% genes of gibberellin and jasmonic acid were changed under COR treatment. Conclusions: These data provide a gene expression profiling in different regions of internode development and molecular mechanism of COR affecting internode elongation. A putative schematic of the internode response to COR treatment is proposed which shows the basic process of COR affecting internode elongation. This research provides a useful resource for studying maize internode development and improves our understanding of the COR regulation mechanism based on plant height. [ABSTRACT FROM AUTHOR]

Ethephon is plant growth regulator widely used to control maize lodging at the early stage of jointing. However, the function and efficacy of ethephon due to differences of cultivars and maize growing areas remains elusive, necessitating the evaluation of each cultivar's sensitivities prior to the application of ethylene. In this study, we collected ten maize cultivars from the largest planted area in China and cultivated in three typical growing areas to evaluate their sensitivity to ethephon. The results showed that ethephon reduced maize plant height, ear height, length of base internode, and generally increased the crushing strength of maize base internode. These traits may enhance maize lodging resistance by reducing the center of gravity of the plant structure. The effect of ethephon varied across growing areas, and cultivars within the same region exhibited distinct sensitivity levels to ethephon. The crushing strength of the eighth internode in maize exhibits a wide range of change and small coefficient of variation. Hence, this index's change range could be utilized to assess the sensitivity of maize cultivars to ethephon in various regions. In addition to agronomic traits, we detected shifts in transcriptional levels related to the signaling pathways of phytohormones, particularly ethylene and gibberellin. These changes reveal the association between transcriptional signaling levels of key factors and the sensitivity to ethylene in ten maize cultivars. The results contribute to our understanding of the lodging resistance in different maize cultivars and evaluation the sensitivity of maize cultivar to ethephon in different growing areas, with implications for comparable pedo-climatic conditions elsewhere. [Display omitted] • The sensitivity of same cultivar to ETH differed in different growing areas, and within the same growing area. • The sensitivity of different cultivars to ETH can be evaluated by the crushing strength of maize eighth internode. • The sensitivity of different cultivars to ETH correlated to the expression level of ETH receptor. [ABSTRACT FROM AUTHOR]

Maize yield is limited by water deficit in the arid and semiarid regions of China. Conserving water and enhancing crop water productivity are inevitable requirements for the sustainable development of water efficient agriculture. Plant growth regulators (PGRs) play important roles in maize water stress tolerance. In this study, we investigated the effect of plant growth regulator-brazide, a functional analog of brassinolide (BR), on maize water stress resistance through a two-year (2020–2021) field experiment. The experiment included four water treatments (I100: 4012 m3 ha−1; I80: 3210 m3 ha−1; I60: 2407 m3 ha−1; I40: 1605 m3 ha−1), four PGR concentrations (CK: water; Bra: 0.1 μmol L−1 14-hydroxylated brassinosteroid; B1: 0.1 μmol L−1 brazide; B2: 1 μmol L−1 brazide; B3: 10 μmol L−1 brazide). The results showed that deficit irrigation (I60 and I40) decreased soil water content (SWC), photosynthetic rate (Pn), leaf area index (LAI), aboveground biomass (AB) and yield, but improved crop water productivity (WP c). Under deficit irrigation conditions, 1 μmol L−1 brazide application also increased dry matter accumulation and grain yield, a result attributed to improvement of the photosynthetic rate and increases in the root bleeding saps, water productivity. 1 μmol L−1 Brazide application reduced bare tip length, increasing kernel number per ear, thereby increased the yield of I60 and I40 by 15.1% and 11.4% (p ≤ 0.05; 2020), 16.4% and 20.4% (p ≤ 0.001; 2021), respectively. Path analysis showed brazide improved final yields by increasing thousand grain weight (TGW), photosynthetic rate (Pn) and WP c under deficit irrigation. The increase in TGW with brazide treatment was primarily attributed to the increase of Pn. Overall, Brazide increased maize drought resistance mainly by increasing Pn and WP c , with 1 μmol L−1 brazide as an optimal concentration. • A new plant growth regulator, Brazide, was evaluated in maize. • Brazide increased photosynthetic rate and WUE under deficit irrigation. • Application of brazide improved maize growth and grain yield under deficit irrigation. • 1 μmol L−1 brazide as an optimal concentration for maize in arid region of Northwest China. [ABSTRACT FROM AUTHOR]

Waterlogging negatively affects maize growth and yield. In this study, we found that ethylene played a vital role in plant adaptation to waterlogging. ET promotes better growth in seedlings under waterlogging conditions by altering root architecture and increasing lateral root formation by 42.1%. What's more, plants with high endogenous ethylene levels exhibited reduced sensitivity to waterlogging stress. ET also induced the formation of aerenchyma, a specialized tissue that facilitates gas exchange, in a different pattern compared to aerenchyma formed under waterlogging. Aerenchyma induced by ET was mainly located in the medial cortex of the roots and was not prone to decay. ethylene inhibited root elongation under normal conditions, but this inhibition was not alleviated under waterlogging stress. Upon activation of the ET signaling pathway, the transcription factor EREB90 promoted aerenchyma formation by enhancing the programmed cell death process. Overexpression of EREB90 resulted in increased waterlogging tolerance compared to wild type plants. Our findings suggest that pre-treatment of maize seedlings with ET before waterlogging stress can trigger the programmed cell death process and induce aerenchyma formation, thus improving waterlogging resistance. [ABSTRACT FROM AUTHOR]

Increasing planting density is important to raise maize yield, however, high density often leads to an increase risk of lodging due to dense canopy and weak stem. Maize yield and optimal plant density are increased by applying plant growth regulator compound of ethephon and DA-6, however, we do not know if this compound would interact with location and genotype. In this study, a novel plant growth regulator, as the synthesis of N , N - diethyl − 2 − hexanoyl oxygen radicals − ethyl amine (2-ethyl chloride) phosphonic acid salt (DHEAP), combining the effects of ethephon and DA-6 in one chemical, was developed and tested at three locations, five plant densities (6.75, 8.25, 9.75, 11.25 and 12.75 plants m −2 ) and three cultivars in 2014–2015. This study aimed to quantify the interactions between environment, genotype and management (Appling DHEAP and plant density) on lodging-related optimal plant density and yield. DHEAP significantly increased grain yield by 10.7% due to the increases of kernel weight by 3.2% and kernel number per ear by 4.4%. On average across genotypes and environments, applying DHEAP increased optimum plant density by 6%. The optimal plant density interacted with cultivar, DHEAP and environment. Applying DHEAP reduced lodging percentage by lowering ear height. The yield-lodging relationship was affected by genotype and location. We concluded that maize yield could be enhanced by optimizing plant density, applying DHEAP and cultivar selection, but climatic and environmental differences of locations should be considered. [ABSTRACT FROM AUTHOR]

The induced electric field assisted hydrochloric acid (IEF-HCl) hydrolysis of potato starch was investigated in a fluidic system. The impact of various reaction parameters on the hydrolysis rate, including reactor number (1–4), salt type (KCl, MgCl 2 , FeCl 3 ), salt concentration (3–12%), temperature (40–55 °C), and hydrolysis time (0–60 h), were comprehensively assessed. Under optimal conditions, the maximum reducing sugar content in the hydrolysates was 10.59 g/L. X-ray diffraction suggested that the crystallinity of IEF-HCl-modified starches increased with the intensification of hydrolysis but was lower than that of native starch. Scanning electron microscopy indicated that the surface and interior regions of starch granules were disrupted by the hydrolysis. The solubility of IEF-HCl-modified starches increased compared to native starch while their swelling power decreased, contributing to a decline in paste viscosity. These results suggest that IEF is a notable potential electrotechnology to conventional hydrolysis under mild conditions without any electrode touching the subject. [ABSTRACT FROM AUTHOR]

Plant growth regulators (PGRs) play crucial roles in maize drought tolerance. However, most of the studies are focused on seedling stage under greenhouse conditions, little is known on the effects of grain yields at later growth stage under field environment. It is hypothesized that exogenous application of PGRs can increase maize drought tolerance at different growth stages under field conditions. Here we used alginate oligosaccharide (AOS) and coronatine (COR) to investigate the effects of these two PGRs on maize drought tolerance in a two-year field experiment. The results showed that both COR and AOS treatments reduced leaf water loss and significantly increased the relative leaf water content by 12.6% and 13.0%, thus significantly decreasing superoxide anion accumulation by 49% and 42% in maize seedlings. There was no big difference between these two treatments in the seedling stage. In the subsequent reproductive growth period, although both COR and AOS treatments significantly increased leaf photosynthesis and above-ground growth, including photosynthetic rate by 41% and 33%, relative chlorophyll content (SPAD value) by 8.0% and 6.5%, leaf area by 22% and 15%, plant height by 8.3% and 5.9%, dry matter accumulation by 23% and 17%, respectively, under drought conditions, the effect of COR was superior to the AOS, as evidenced by membership function values of COR treatment were 0.12 and 0.08 larger than that of AOS treatment in 2020 and 2021, respectively. Ultimately, COR and AOS treatments significantly increased the grain yields by 21.7% and 16.2% in 2020, 22.3% and 15.7% in 2021, respectively, under drought conditions. Path analysis showed both PGRs increased final grain yields by increasing thousand-kernel weight (TKW). While the TKW increase with COR treatment was mainly due to the increase of relative chlorophyll content (SPAD value), AOS treatment mainly increased dry matter accumulation under drought conditions. [Display omitted] • Effects of coronatine (COR) and alginate oligosaccharide (AOS) on drought tolerance examined. • Both COR and AOS treatments improved maize drought tolerance. • Treatment of maize seedling contributed to the whole growth period. • The COR treatment was more pronounced in the reproductive growth period. • The COR treatment was superior to that of the AOS treatment. [ABSTRACT FROM AUTHOR]

The effects of induced electric field (IEF) on the crystal structure and physicochemical properties of potato starch were investigated by subjecting identically treated control and electrically-modified samples to the same temperature history. Additionally, a method of combining IEF with heating for efficient modification of native polymer was also proposed. Results showed that the application of IEF at an electric voltage of 75 V has a statistically significant effect on starch gelatinization and pasting properties, especially when combined with heating at 50 °C. After treatment by the combination method for 96 h, the gelatinization temperatures increased, which can be explained by the slight increase in the ratio of 1044/1015 cm −1 and relative crystallinity. Furthermore, IEF reduced granular swelling and therefore contributed to decreasing the peak, breakdown, and setback viscosity of potato starch. This study explores the potential of IEF as innovative technology for starch modification. [ABSTRACT FROM AUTHOR]

Salt stress negatively affects maize growth and yield. Application of plant growth regulator is an effective way to improve crop salt tolerance, therefore reducing yield loss by salt stress. Here, we used a novel plant growth regulator B2, which is a functional analogue of ABA. With the aim to determine whether B2 alleviates salt stress on maize, we studied its function under hydroponic conditions. When the second leaf was fully developed, it was pretreated with 100 µM ABA, 0.01 µM B2, 0.1 µM B2, and 1 µM B2, independently. After 5 days treatment, NaCl was added into the nutrient solution for salt stress. Our results showed that B2 could enhance salt tolerance in maize, especially when the concentration was 1.0 µMol·L−1. Exogenous application of B2 significantly enhanced root growth, and the root/shoot ratio increased by 7.6% after 6 days treatment under salt stress. Compared with control, the ABA level also decreased by 31% after 6 days, which might have resulted in the root development. What is more, B2 maintained higher photosynthetic capacity in maize leaves under salt stress conditions and increased the activity of antioxidant enzymes and decreased the generation rate of reactive oxygen species by 16.48%. On the other hand, B2 can enhance its water absorption ability by increasing the expression of aquaporin genes ZmPIP1-1 and ZmPIP1-5. In conclusion, the novel plant growth regulator B2 can effectively improve the salt tolerance in maize. [ABSTRACT FROM AUTHOR]

• Reduced irrigation decreased SWC, LAI, biomass, yield and ET, but improved WUE. • Increasing planting density increased LAI and ET, but reduced SWC and biomass. • Planting density had significant effects on yield and WUE. • MI-D2 is recommended for spring maize production in the Northwest China. The limited availability of water resources severely restricts agricultural development in the semiarid and arid regions of Northwest China. A two-year field experiment was conducted to investigate the effects of irrigation and planting density on the soil water content (SWC), growth and development, yield, water use efficiency (WUE) and economic benefits of spring maize in arid areas under mulch drip irrigation system. The optimized combination of irrigation and planting densities for high grain yield, WUE and net return were obtained by multiple regression analysis. Experiment included three irrigation treatments (HI: 450 mm; MI: 337.5 mm; LI: 225 mm) and four planting densities (D1: 75,000 plants ha−1; D2: 90,000 plants ha−1; D3: 105,000 plants ha−1; D4: 120,000 plants ha−1). The results showed that the reduction of irrigation decreased SWC, leaf area index (LAI), aboveground biomass, yield and evapotranspiration (ET), but improved WUE. HI and MI were significantly different from LI. Increasing planting density increased LAI and ET, but reduced SWC and aboveground biomass. Planting density had significant effects on yield and WUE, which differed in both years. The overall yield, WUE and net return were greater than the two-year average of HI-D1 under an irrigation amount of 271.9–500.2 mm and a planting density range of 7.1–14.3 × 104 plants ha-1. MI-D2, with 25 % reduced irrigation, increased the two-year average yield, WUE and net return by 5.2 %, 20.2 % and 27.2 %, respectively, compared to HI-D1. Therefore, irrigation of 337.5 mm at a medium planting density of 90,000 plants ha-1 under mulch drip irrigation is recommended for spring maize production in the drylands of Northwest China in our research. [ABSTRACT FROM AUTHOR]

• DHEAP is a novel plant growth regulator. • DHEAP improved maize lodging resistance. • DHEAP shaped a compact maize plant type. • DHEAP is helpful to increases summer maize planting density in NCP. Increasing the planting density (PD) of maize (Zea mays L.) crops is the most efficient method for enhancing maize grain yield, but supra-optimum PD leads to an increase in lodged maize, which alters the maize canopy structure. In this study, N, N-Diethyl-2-hexanoyl oxygen radicals-ethyl amine (2-ethyl chloride) phosphonic acid salt (DHEAP, a single compound), a novel plant growth regulator, was sprayed at the seven-expanded-leaf stage under two different PDs (75,000, and 90,000 plants ha-1) using two maize hybrids, ZD958 (lodging-resistance) and XY335 (lodging-susceptible), to reduce maize lodging rates and improve the maize canopy structure under high PD. After DHEAP treatment, the maize lodging rate of ZD958 and XY335 decreased by 70.87% and 75.22%, respectively, through a change in the morphological structure (i.e., reduced plant and ear heights and increased mean tilt angle) and an improvement in the basal internode quality (i.e., increased diameter, dry weight per unit length, crushing strength, cellulose content, lignin content, and vascular area, and reduced length). In addition, DHEAP treatment significantly reduced gibberellin (GA 3) contents in maize basal internodes. Moreover, the increase in the mean tilt angle (MTA) above the maize ear leaf after DHEAP treatment improved the light penetration in the middle leaf strata, which increased the chlorophyll content (SPAD), net photosynthetic rate (P n), and Rubisco enzyme activities. Finally, DHEAP treatment increased the grain yield of ZD958 and XY335 under 90,000 PD by 22.28% and 43.14%, respectively. Thus, it was concluded that the spraying of DHEAP effectively reduced maize lodging rates and improved the photosynthetic performance of the maize ear leaf, which increased maize grain yield under high PDs. [ABSTRACT FROM AUTHOR]

Coronatine (COR) is a phytotoxin produced by the pathogen Pseudomonas syringae, it has a structure similar to that of jasmonates (JAs), but it is much more active as a plant growth regulator. The goal of this study was to gain more insight into the effect and the mechanism of COR effects on stalk characteristics are related lodging resistance of maize. The agronomic traits, stalk ultrastructure, and endogenous hormones in maize stalks were studied in field trails and greenhouses, using hybrid cultivar "Xianyu 335" (XY335), "Zhengdan 958" (ZD958) and inbred line B73 as materials in 2018 and 2019. Different concentration of COR were sprayed onto maize foliar surfaces at the seven-expanded-leaves (V7) stage. Foliar application with 10 µmol L−1 of COR at the V7 stage decreased plant and ear height, increased weight and diameter of the basal internodes, and increased penetration strength and stalk bending resistance. Compared to the control treatment, in COR-treated plants, salicylic acid (SA) and jasmonic acid (JA) were decreased significantly in stalks. The treatment of 10 µmol L−1 of COR enhanced lignin accumulation, the integrity, and the thickness of cell walls in maize stalks in the early stages of stem growth in the inbred line B73, as revealed by autofluorescence microscopy and scanning electron micrographs. Our results indicated that COR improved stalk bending resistance of maize not only by optimizing stalk morphological characteristics, but also by altering hormone levels, which may led to greater lignin accumulation, thickens cell wall, and decreased the area of vascular bundles. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs), the post-transcriptional gene regulators, are known to play an important role in plant development. The identification of differentially expressed miRNAs could better help us understand the post-transcriptional regulation that occurs during maize internode elongation. Accordingly, we compared the expression of MIRNAs between fixed internode and elongation internode samples and classified six differentially expressed MIRNAs as internode elongation-responsive miRNAs including zma-MIR160c, zma-MIR164b, zma-MIR164c, zma-MIR168a, zma-MIR396f, and zma-MIR398b, which target mRNAs supported by transcriptome sequencing. Functional enrichment analysis for predictive target genes showed that these miRNAs were involved in the development of internode elongation by regulating the genes respond to hormone signaling. To further reveal how miRNA affects internode elongation by affecting target genes, the miRNA–mRNA–PPI (protein and protein interaction) network was constructed to summarize the interaction of miRNAs and these target genes. Our results indicate that miRNAs regulate internode elongation in maize by targeting genes related to cell expansion, cell wall synthesis, transcription, and regulatory factors. [ABSTRACT FROM AUTHOR]

Coronatine (COR) is a structural and functional analog of methyl jasmonic acid (MeJA), which can alleviate stress on plant. We studied the effects of COR on the drought stress of rice (Oryza sativa L.). Pre-treatment with COR significantly increased the biomass, relative water and proline content, and DPPH (1,1-diphenyl-2-picrylhydrazyl)-radical scavenging activity, decreased the electrolyte leakage and MDA (Malondialdehyde) content in order to maintain the stability of cell membrane. Meanwhile, we determined how COR alleviates water stress by Nipponbare gene expression profiles and cDNA microarray analyses. Seedlings were treated with 0.1 μmol L−1 COR at the three leafed stage for 12 h, followed with 17.5% polyethylene glycol (PEG). Whole genome transcript analysis was determined by employing the Rice Gene Chip (Affymetrix), a total of 870 probe sets were identified to be up or downregulated due to COR treatment under drought stress. Meanwhile, the real-time quantitative PCR (RT-qPCR) method was used to verify some genes; it indicated that there was a good agreement between the microarray data and RT-qPCR results. Our data showed that the differentially expressed genes were involved in stress response, signal transduction, metabolism and tissue structure development. Some important genes response to stress were induced by COR, which may enhance the expression of functional genes implicated in many kinds of metabolism, and play a role in defense response of rice seedling to drought stress. This study will aid in the analysis of the expressed gene induced by COR. [ABSTRACT FROM AUTHOR]