The pathogenesis of wheat powdery mildew (WPM) is from the bottom to upper layers of the plant, and the vertical observation angle limits the early monitoring of WPM status. Multiangle remote sensing ...could effectively extract spatial structural information from different plant layers. The objectives of this study were to improve the monitoring accuracy of WPM severity and to screen suitable observation angles by developing a novel vegetation index. The monitoring capacities of the novel parameters Normalized Powdery Mildew Index (NPMI) and Ratio Powdery Mildew Index (RPMI) and 14 optimized traditional spectral parameters were compared at 13 observation angles and different angle ranges. The correlation between all spectral parameters and disease severity was superior in the forward observation direction than in the backward observation direction in the principal plane of the Sun, and the correlation between the two observation directions decreased with an increase in observation angle. The new spectral parameter suitable for inversion of disease index was RPMI (<inline-formula> <tex-math notation="LaTeX">{R}_{744}/{R}_{762}-0.5 \times R_{710} </tex-math></inline-formula>), and the best optimal observation angle was +10°, with a 0.852 coefficient, which was 31.74% higher than that of the two-band spectral parameter, <inline-formula> <tex-math notation="LaTeX">{R}_{744}/{R}_{762} </tex-math></inline-formula>. The fitting accuracy of the new parameter in the range of 0° to +30° in the forward direction was 0.704. RPMI could not only improve the monitoring accuracy of powdery mildew severity at a single angle but also achieve a more stable monitoring accuracy in the 0° to +30° range in the forward direction, which significantly expands the application scope of remote sensing monitoring and enhances the flexibility of the technology in actual production environments.
Glutathione S-transferase (GST) is the key enzyme in glutathione (GSH) synthesis, and plays a crucial role in copper (Cu) detoxification. Nonetheless, its regulatory mechanisms remain largely ...unclear. In this study, we identified a Cu-induced glutathione S-transferase 1 (TaGST1) gene in wheat. Yeast one-hybrid (Y1H) screened out TaWRKY74, which was one member from the WRKY transcription factor family. The bindings between TaGST1 promoter and TaWRKY74 were further verified by using another Y1H and luciferase assays. Expression of TaWRKY74 was induced more than 30-folds by Cu stress. Functions of TaWRKY74 were tested by using transiently silence methods. In transiently TaWRKY74-silenced wheat plants, TaWRKY74 and TaGST1 expression, GST activity, and GSH content was significantly inhibited by 25.68%, 19.88%, 27.66%, and 12.68% in shoots, and 53.81%, 52.11%, 23.47%, and 17.11% in roots, respectively. However, contents of hydrogen peroxide, malondialdehyde, or Cu were significantly increased by 2.58%, 12.45%, or 37.74% in shoots, and 25.24%, 53.84%, and 103.99% in roots, respectively. Notably, exogenous application of GSH reversed the adverse effects of transiently TaWRKY74-silenced wheat plants during Cu stress. Taken together, our results suggesting that TaWRKY74 regulated TaGST1 expression and affected GSH accumulation under Cu stress, and could be useful to ameliorate Cu toxicity for crop food safety.
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•Cu stress quickly induced expression of TaGST1, which catalyzed synthesis of GSH.•Y1H screen out TaWRKY74, which was bound to TaGST1 promoter via the W-box sequence.•TaWRKY74 regulated TaGST1 expression, GST activity and GSH content under Cu stress.•GSH significantly alleviated the damage caused by Cu stress of TaWRKY74-silencing plants.
Relationships between vegetation indices (VIs) and leaf area index (LAI) tend to saturate in the nadir direction, and vary with crop canopy structure and view zenith angles (VZAs). The objective of ...this paper was to improve the monitoring accuracy and angular stability of VIs for estimating LAI using multiangular remote sensing data. The relationship between LAI and ground-based hyperspectral spectral reflectance was quantified in winter wheat (Triticum aestivum L.) exhibiting erectophile and planophile growth habits. To further reduce the saturation, species specificity, and angular sensitivity, we developed a saturation factor (SF), based on near-infrared and green bands. Multiplying all VIs by SF greatly improved the association with LAI across all VZAs (<inline-formula> <tex-math notation="LaTeX">R^{2} = 0.73{-}0.82 </tex-math></inline-formula>). Most VI <inline-formula> <tex-math notation="LaTeX">\times </tex-math></inline-formula> SF values, particularly optimized soil-adjusted VI <inline-formula> <tex-math notation="LaTeX">\times </tex-math></inline-formula> SF, were able to construct universal algorithms across VZAs for accurate estimation of LAI due to the sensitivity of SF to LAI in a dense canopy, and the insensitivity of SF to view effects with larger VZAs. This approach is also promising for the exploitation of multiangular satellite data for the design and calibration of nonview-angle-corrected spectral reflectance, for which the sensor is only deployed at fixed observation direction.
Periodontitis and hypertension often occur as comorbidities, which need to be treated at the same time. To resolve this issue, a controlled‐release composite hydrogel approach is proposed with dual ...antibacterial and anti‐inflammatory activities as a resolution to achieve the goal of co‐treatment of comorbidities. Specifically, chitosan (CS) with inherent antibacterial properties is cross‐linked with antimicrobial peptide (AMP)‐modified polyethylene glycol (PEG) to form a dual antibacterial hydrogel (CS‐PA). Subsequently, curcumin loaded into biodegradable nanoparticles (CNP) are embedded in the hydrogel exhibiting high encapsulation efficiency and sustained release to achieve long‐term anti‐inflammatory activities. In a mouse model of periodontitis complicated with hypertension, CS‐PA/CNP is applied to gingival sulcus and produced an optimal therapeutic effect on periodontitis and hypertension simultaneously. The therapeutic mechanisms are deeply studied and indicated that CS‐PA/CNP exerted excellent immunoregulatory effects by suppressing the accumulation of lymphocytes and myeloid cells and enhanced the antioxidant capacity and thus the anti‐inflammatory capacity of macrophages through the glutathione metabolism pathway. In conclusion, CS‐PA/CNP has demonstrated its superior therapeutic effects and potential clinical translational value in the co‐treatment of periodontitis and hypertension, and also serves as a drug delivery platform to provide combinatorial therapeutic options for periodontitis with complicated pathogenesis.
CS‐PA hydrogel with dual antibacterial activities is fabricated through the thiol‐maleimide click reaction, where curcumin nanoparticles are physically incorporated. By in situ injection of the hydrogel into periodontal pockets, CS‐PA/CNP can inhibit various periodontal pathogens and restore immune hemostasis to effectively manage periodontitis, which reverses periodontitis‐exacerbated hypertension in the meantime.
•Multi-angular vegetation indices (MAVI) for estimating LNC in wheat were developed.•Optimal wavelengths and viewing zenith angles were determined and characterized.•These indices were compared with ...existing traditional indices.•Our MAVI model improves LNC estimation from remote sensing data by 9.4%.
Real-time, nondestructive estimation of crop nitrogen (N) status is highly important for precision N management in winter wheat production. Developing a new N indicator based on the direct link between spectral index and chlorophyll content is important for crop N diagnosis. In this study, we investigated the quantitative relationships between leaf N concentration (LNC) and ground-based multi-angular remote sensing hyperspectral reflectance in winter wheat (Triticum aestivum L.). Field experiments were conducted from 2011 to 2014 across different sites, cultivars, growth stages, N rates, and planting densities, and a novel Multi-angular vegetation index (MAVISR) was developed to improve the prediction accuracy and stability of LNC measurement. The optimum vegetation indices (VIs) obtained from 40 traditional indices reported in the literature, as well as normalized difference spectral indices (ND) and Simple Ratio Indices (SR), were tested for their stability in estimating LNC at 13 viewing zenith angles (VZAs). Overall, the coefficient of determination (r2) of spectral reflectance and traditional VIs with LNC decreased with increasing VZA in both the forward and backward scattering directions and reached maximum values at a viewing angle of −20°. Ratio index (RI-1dB) exhibited the best linear relationship to LNC (r2 of 0.837) at the −20° viewing angle, but Enhanced vegetation index (EVI-1) showed the highest r2 (0.819) with LNC at the nadir direction. The relationships between the LNC and two-band combinations indicate that there are three sensitive regions with high r2, which vary with VZA, usually comprising combinations of blue–red wavelengths, green–red edge wavelengths, and between-red edge wavelengths. To further analyze the relationship between the combination of the three sensitive regions and the sensitive VZAs with LNC, the MAVISR index in the form of MAVISR=(R538/R768)−20−(R478/R634)+10 was calculated and found to be highly correlated with LNC (r2=0.897). When independent data were fit to the derived equations, the average relative error (RE) values were 15.5%, 14.3%, and 12.6% between measured and estimated LNC using EVI-10°, RI-1dB−20°, and MAVISR, respectively. These results suggest that the models can accurately estimate LNC in wheat, and the novel MAVISR is more effective for estimating LNC than previously reported VIs, independent of years, sites, and growth periods. The results also indicate the importance of taking into account angle effects when analyzing VIs.
Melatonin (MT) is involved in various physiological processes and stress responses in animals and plants. However, little is known about the molecular mechanisms by which MT regulates potassium ...deficiency (DK) tolerance in crops. In this study, an appropriate concentration (50 μmol/L) was found to enhance the tolerance of wheat plants against DK. RNA‐seq analysis showed that a total of 6253 and 5873 differentially expressed genes (DEGs) were separately identified in root and leaf tissues of the DK + MT‐treated wheat plants. They functionally involved biological processes of secondary metabolite, signal transduction, and transport or catabolism. Of these, an upregulated high‐affinity K transporter 1 (TaHAK1) gene was next characterized. TaHAK1 overexpression markedly enhanced the K absorption, while its transient silencing exhibited the opposite effect, suggesting its important role in MT‐mediated DK tolerance. Moreover, yeast one‐hybrid (Y1H) was used to screen the upstream regulators of TaHAK1 gene and the transcription factor TaNAC71 was identified. The binding between TaNAC71 and TaHAK1 promoter was evidenced by using Y1H, LUC, and EMSA assays. Transient overexpression of TaNAC71 in wheat protoplasts activated the TaHAK1 expression, whereas its transient silencing inhibited the TaHAK1 expression and aggravated the sensitivity to DK. Exogenous MT application greatly upregulated the expression of TaHAK1 in both transient overexpression and silencing systems. Our findings revealed some molecular mechanisms underlying MT‐mediated DK tolerance and helped broaden its practical application in agriculture.
Abstract
Background
Parkinson’s disease (PD) is a common chronic neurological disorder with a high risk of disability and no cure. Periodontitis is an infectious bacterial disease occurring in ...periodontal supporting tissues. Studies have shown that periodontitis is closely related to PD. However, direct evidence of the effect of periodontitis on PD is lacking. Here, we demonstrated that ligature-induced periodontitis with application of subgingival plaque (LIP-SP) exacerbated motor dysfunction, microglial activation, and dopaminergic neuron loss in 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice.
Results
The 16S rRNA gene sequencing revealed that LIP-SP induced oral and gut dysbiosis. Particularly,
Veillonella parvula
(
V. parvula
) and
Streptococcus mutans
(
S. mutans
) from oral ligatures were increased in the fecal samples of MPTP + LIP-SP treated mice. We further demonstrated that
V. parvula
and
S. mutans
played crucial roles in LIP-SP mediated exacerbation of motor dysfunction and neurodegeneration in PD mice.
V. parvula
and
S. mutans
caused microglial activation in the brain, as well as T helper 1 (Th1) cells infiltration in the brain, cervical lymph nodes, ileum and colon in PD mice. Moreover, we observed a protective effect of IFNγ neutralization on dopaminergic neurons in
V. parvula-
and
S. mutans-
treated PD mice.
Conclusions
Our study demonstrates that oral pathogens
V. parvula
and
S. mutans
necessitate the existence of periodontitis to exacerbate motor dysfunction and neurodegeneration in MPTP-induced PD mice. The underlying mechanisms include alterations of oral and gut microbiota, along with immune activation in both brain and peripheral regions.
Water shortage has threatened sustainable development of agriculture globally as well as in the North China Plain（NCP）.Irrigation,as the most effective way to increase food production in dry land,may ...not be readily available in the situation of drought.One of the alternatives is to supply plants with enough nutrients so that they can be more sustainable to the water stress.The objective of this study was to explore effects of irrigation and sulphur（S）application on water consumption,dry matter accumulation（DMA）,and grain yield of winter wheat in NCP.Three irrigation regimes including no irrigation（rainfed,I0）during the whole growth period,once irrigation only at jointing stage（90 mm,I1）,and twice respective irrigation at jointing and anthesis stages（90 mm plus 90 mm,I2）,and two levels of S application including 0S0and 60 kg ha^–1（S60）were designed in the field experiment in NCP.Results showed that increasing irrigation times significantly increased mean grain yield of wheat by 12.5–23.7%and nitrogen partial factor productivity（NPFP）by 21.2–45.0%in two wheat seasons,but markedly decreased crop water use efficiency（YWUE）.Furthermore,S supply 60 kg ha^–1 significantly increased mean grain yield,YWUE,IWUE and NPFP by 5.6,6.1,23.2,and 5.6%（across two wheat seasons）,respectively.However,we also found that role of soil moisture prior to S application was one of important greater factors on improving the absorption and utilization of storage water and nutrients of soil.Thus,water supply is still the most important factor to restrict the growth of wheat in the present case of NCP,supplying 60 kg ha^–1 S with once irrigation 90 mm at the jointing stage is a relatively appropriate recommended combination to improve grain yield and WUE of wheat when saving water resources is be considered in irrigated wheat farmlands of NCP.
Scientific management of nitrogen (N) fertilizer has a significant effect on yield while also reducing the environmental risks. In this study, we conducted field experiments over three years at two ...different sites (Zhengzhou and Shangshui) in Henan Province, China, using different N application rates (0, 90,180, 270, and 360 kg ha
) to determine the relationships between soil N supply and N demand in winter wheat (Triticum aestivum L.). Optimal N input was then determined. Both sites showed the same trend. Namely, aboveground N uptake and soil nitrate N (NO
-N) increased with increasing N, while NO
-N decreased with increasing soil depth, gradually moving downwards with growth. A significant correlation (p < 0.001) between increasing aboveground N uptake and increasing NO
-N was also observed under N application, with the best relationships occurring in the 20-60 cm layer during jointing-anthesis (R
= 0.402-0.431) and the 20-80 cm layer at maturity (R
= 0.474). Root weight density showed the same spatial-temporal characteristics as NO
-N, following a unimodal trend with increasing N, and peaking at 90 kg ha
. The root weight density was mainly distributed in the 0-60 cm layer (above 80%), with the 20-60 cm layer accounting for 30% of the total root system. In this layer, the root weight density was also significantly positively correlated with aboveground N uptake. Wheat yield reached saturation under high N (>270 kg ha
), with a sharp decrease in N use efficiency (NUE) and linear increase in residual NO
-N. To balance yield and the risk of environmental pollution in the experimental area, an N application rate of 180-270 kg ha
is recommended under sufficient irrigation, thereby supporting a well-developed root system while ensuring balance between N supply and demand.
Psoriasis is a multisystem disease affecting about 2% of the population, while keratin16 (KRT16) has been reported to participate in psoriasis. However, the specific mechanism of KRT16 in psoriasis ...was inadequately investigated. The objective of the study was to elucidate the mechanism by which siRNA‐mediated silencing of KRT16 affects keratinocyte proliferation and vascular endothelial growth factor (VEGF) secretion in psoriasis through the extracellular signal‐related kinase (ERK) signaling pathway. Psoriasis‐related core gene KRT16 was screened out. Then, the expression of KRT16, VEGF, and ERK signaling pathway‐related genes was detected in psoriatic patients. To further investigate the mechanism of KRT16, keratinocytes in psoriatic patients were treated with KRT16 siRNA or/and ERK inhibitor (PD98059) to detect the changes in related gene expression and cell survival. KRT16 was involved in psoriasis development. The expression levels of KRT16, p‐ERK1/2, and VEGF in lesion tissues are significantly elevated. Keratinocytes treated with KRT16‐siRNA and KRT16‐siRNA + PD98059 exhibited reduced KRT16, p‐ERK1/2, and VEGF expression. The cell survival rate in cells treated with KRT16‐siRNA, PD98059, and KRT16‐siRNA + PD98059 reduced significantly. These findings indicate that silencing KRT16 inhibits keratinocyte proliferation and VEGF secretion in psoriasis via inhibition of ERK signaling pathway, which provides a basic theory in the treatment of psoriasis.
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