Amino acid conjugates of pesticides can promote the phloem translocation of parent ingredients, allowing for the reduction of usage, and decreased environmental pollution. Plant transporters play ...important roles in the uptake and phloem translocation of such amino acid-pesticide conjugates such as L-Val-PCA (L-valine-phenazine-1-carboxylic acid conjugate). However, the effects of an amino acid permease, RcAAP1, on the uptake and phloem mobility of L-Val-PCA are still unclear. Here, the relative expression levels of
were found to be up-regulated 2.7-fold and 2.2-fold by the qRT-PCR after L-Val-PCA treatments of
cotyledons for 1 h and 3 h, respectively. Subsequently, expression of
in yeast cells increased the L-Val-PCA uptake (0.36 μmol/10
cells), which was 2.1-fold higher than the control (0.17 μmol/10
cells). Pfam analysis suggested RcAAP1 with its 11 transmembrane domains belongs to the amino acid transporter family. Phylogenetic analysis found RcAAP1 to be strongly similar to AAP3 in nine other species. Subcellular localization showed that fusion RcAAP1-eGFP proteins were observed in the plasma membrane of mesophyll cells and phloem cells. Furthermore, overexpression of
for 72 h significantly increased the phloem mobility of L-Val-PCA in
seedlings, and phloem sap concentration of the conjugate was 1.8-fold higher than the control. Our study suggested that RcAAP1 as carrier was involved in the uptake and phloem translocation of L-Val-PCA, which could lay foundation for the utilization of amino acids and further development of vectorized agrochemicals.
•Established the Minimum data set (MDS) indicators for cultivated-layer soil quality (CLSQ) diagnosis.•The CLSQI was generally between the reasonable (III) and unreasonable (IV) levels of red soil ...sloping farmland in southern China .•Defined the thresholds of MDS indicators for reasonable cultivated-layer construction.•Subsoiling is recommended for the recovery and improvement of CLSQ, and compaction exert an adverse impact on it.
Tillage is known to potentially affect soil quality in various ways, and employing appropriate tillage measures is crucial to construct a reasonable cultivated layer (RCL), which could maximize the storage and coordination of water, gas and heat conditions in the cultivated layer of red soil sloping farmland. This study aims to 1) select the key indicators to establish a minimum data set (MDS), 2) evaluate the quality of cultivated-layer soil and define the indicator threshold for RCL construction, and 3) develop a credible cultivated-layer soil quality index (CLSQI) for the cultivated layer with different tillage measures, and screen suitable tillage measures to improving the soil productivity of red soil sloping farmland. Taking the red soil sloping farmland in China as the research focus, the MDS is established by principal component analysis (PCA) in conjunction with the norm value, Furthermore, the membership function models (S type, anti-s-type, Parabola-type) are used to normalize the indicator data and then assess the CLSQ based on the CLSQI approache, determine the indicator threshold by the CLSQ grade and membership function model, and analyse the cultivated-layer improvement effect by different tillage measures. The results indicated that the MDS and the thresholds of six indicators defined as the cultivated-layer thickness (CLT ≥ 20.39 cm), saturated hydraulic conductivity (SHC ≥ 6.24 mm/min), shear strength (SS ≥ 3.16 kg/cm2), clay content of 10.0–28.1%, organic matter (OM ≥ 15.23 g/kg) and available phosphorus (AP ≥ 58.48 mg/kg), were established in this research for the soil quality assessment of red soil sloping farmland. Tillage methods notably influenced these indicators and CLSQ, and the CLSQI was the highest for subsoiling (0.58) and lowest for soil compaction (0.37); however, mechanical compaction imposed a negative impact on the CLSQ under agricultural modernization, so subsoiling was the recommended measure for the production of soil conditions in this area. Our findings demonstrated that the sloping farmland resources in the research area should be reasonably utilized for the construction of an RCL, and effective subsoiling was suggested for good recovery of cultivated-layer soil capacity and function to increase the CLSQ. Smallholder farmers should therefore be aware of the potential for high soil quality in the future as a result of subsoiling and maintain the soil indicators at a suitable or even high level.
The natural pesticide phenazine-1-carboxylic acid (PCA) is known to lack phloem mobility, whereas Metalaxyl is a representative phloem systemic fungicide. In order to endow PCA with phloem mobility ...and also enhance its antifungal activity, thirty-two phenazine-1-carboxylic acid-
-phenylalanine esters conjugates were designed and synthesized by conjugating PCA with the active structure
-acylalanine methyl ester of Metalaxyl. All target compounds were characterized by
H NMR,
C NMR and HRMS. The antifungal evaluation results revealed that several target compounds exhibited moderate to potent antifungal activities against
,
,
,
. In particular, compound
displayed excellent antifungal activity against
with an EC
value of 6.57 µg/mL, which was superior to that of Metalaxyl. Phloem mobility study in castor bean system indicated good phloem mobility for the target compounds
-
. Particularly, compound
exhibited excellent phloem mobility; the content of compound
in the phloem sap of castor bean was 19.12 μmol/L, which was six times higher than Metalaxyl (3.56 μmol/L). The phloem mobility tests under different pH culture solutions verified the phloem translocation of compounds related to the "ion trap" effect. The distribution of the compound
in tobacco plants further suggested its ambimobility in the phloem, exhibiting directional accumulation towards the apical growth point and the root. These results provide valuable insights for developing phloem mobility fungicides mediated by exogenous compounds.
Chilo suppressalis
Walker (Lepidoptera: Crambidae) is a devastating rice crop pest in China. Chemical insecticides have been used to effectively managing
C
.
suppressalis
field populations in most of ...China’s agricultural regions. However, due to the intensive and extensive application of these insecticides,
C
.
suppressalis
has developed widespread resistance to many active ingredients. Thus, insecticide resistance development is a genuine concern for all crop specialists and growers. In this study, using the topical application method, we assessed the susceptibility of forty-six field populations of
C
.
suppressalis
to three insecticides in three Central Chinese provinces from 2010 to 2021. Our findings revealed that field populations of
C
.
suppressalis
built moderate to high levels of resistance to triazophos (Resistance Ratio (RR) = 41.9–250.0 folds), low to moderate levels of resistance to chlorpyrifos (RR = 9.5–95.2 folds), with the exception of the Zhijiang population in 2013 and the Xinyang population in 2015 at 4.8 folds and 3.4 folds resistance rates, respectively, despite showing susceptibility, and low and moderate levels of resistance to abamectin (RR = 4.1–53.5 folds). There were significant correlations between the activity of the detoxification enzymes (CarE) and the log LD
50
values of triazophos. These results should help effective insecticide resistance management strategies reduce the risk of rapid build-ups of resistance to insecticides and slow down the process of selection for insecticide resistance.
In the search for crop protectants, amino acid ester conjugates have been widely investigated as potential antifungal agents. In this study, a series of rhein-amino acid ester conjugates were ...designed and synthesized in good yields, and their structures were confirmed by
H-NMR,
C-NMR and HRMS. The bioassay results revealed that most of the conjugates exhibited potent inhibitory activity against
and
. In particular, conjugate
had the highest antifungal activity against
with an EC
value of 0.125 mM. For
, conjugate
showed the highest antifungal activity with an EC
value of 0.114 mM. Satisfactorily, conjugate
exhibited better protective effects than that of the positive control, physcion, against powdery mildew in wheat. This research supports the role of rhein-amino acid ester conjugates as potential antifungal agents for plant fungal diseases.
Crop fungal diseases pose a serious threat to global crop production and quality. Developing new and efficient fungicides is an important measure to control crop diseases. Phenylthiazole was found to ...be an excellent antifungal skeleton based on our previous study on the structural optimization and biological activity of the natural product thiasporine A. To find new fungicides, 45 phenylthiazole derivatives containing an acylhydrazone moiety were designed and synthesized by the principle of active substructure splicing. Forty-two of the forty-five compounds are novel, except for compounds E1, E14, and E33. Their structures were structurally characterized by 1H NMR, 13C NMR, and HRMS. The antifungal activities of the target compounds against Magnaporthe oryzae Colletotrichum camelliaet, Bipolaris maydis, and Sclerotinia sclerotiorum were evaluated at 25 μg/mL. The bioassay results revealed that most of these compounds exhibited excellent antifungal activities against M. oryzae and C. camelliaet at 25 μg/mL. In particular, compounds E4, E10, E14, E17, E23, E26, and E27 showed the inhibition rate of more than 80% against M. oryzae, with EC50 values of 1.66, 2.01, 2.26, 1.45, 1.50, 1.29, and 2.65 μg/mL, respectively, which were superior to that of the commercial fungicides Isoprothiolane (EC50 = 3.22 μg/mL) and Phenazine-1-carboxylic acid (EC50 = 27.87 μg/mL). The preliminary structure–activity relationship (SAR) results suggested that introducing methyl, halogen, or methoxy at the ortho-position of R1 and the para-position of R2 can endow the final structure with excellent antifungal activity against M. oryzae. The current results provide useful data for developing phenylthiazole derivatives as new fungicides for controlling rice blast caused by M. oryzae.
Human-object interaction (HOI) detection aims to localize and recognize the relationship between humans and objects, which helps computers understand high-level semantics. In HOI detection, two-stage ...and one-stage methods have distinct advantages and disadvantages. The two-stage methods can obtain high-quality human-object pair features based on object detection but lack contextual information. The one-stage transformer-based methods can model good global features but cannot benefit from object detection. The ideal model should have the advantages of both methods. Therefore, we propose the Pairwise Convolutional neural network (CNN)-Transformer (PCT), a simple and effective two-stage method. The model both fully utilizes the object detector and has rich contextual information. Specifically, we obtain pairwise CNN features from the CNN backbone. These features are fused with pairwise transformer features to enhance the pairwise representations. The enhanced representations are superior to using CNN and transformer features individually. In addition, the global features of the transformer provide valuable contextual cues. We fairly compare the performance of pairwise CNN and pairwise transformer features in HOI detection. The experimental results show that the previously neglected CNN features still have a significant edge. Compared to state-of-the-art methods, our model achieves competitive results on the HICO-DET and V-COCO datasets.
The effective functionalization and self-assembly of MXene are of crucial importance for a broad range of nanomaterial applications. In this work, we investigated the aggregates of sulfanilic ...acid-modified MXene (abbreviated as MXene-SO3H) with three model dyes at the air⁻water interface and demonstrated the morphological and aggregation changes of composite films, using Langmuir-Blodgett (LB) technology, as well as excellent uniformity and reproducibility by using surface-enhanced Raman scattering (SERS) spectra. This research has found that cationic dye molecules were adsorbed onto negatively charged MXene-SO3H particles mainly through electrostatic interaction and the particles induced dyes to form highly ordered nanostructures including H- and/or J-aggregates corresponding to monomers in bulk solution. The surface pressure-area isotherms from different dye sub phases confirmed that the stable composite films have been successfully formed. And the spectral results reveal that different dyes have different types of aggregations. In addition, the SERS spectra indicated that the optimal layers of MXene-SO3H/methylene blue (MB) films was 50 layers using rhodamine 6G (R6G) as probe molecule. And the formed 50 layers of MXene-SO3H/MB films (MXene-SO3H/MB-50) as SERS substrate were proved to possess excellent uniformity and repeatability.
To effectively control the infection of plant pathogens, we designed and synthesized a series of phenylthiazole derivatives containing a 1,3,4-thiadiazole thione moiety and screened for their ...antibacterial potencies against
,
pv.
, as well as their antifungal potencies against
,
,
and
. The chemical structures of the target compounds were characterized by
H NMR,
C NMR and HRMS. The bioassay results revealed that all the tested compounds exhibited moderate-to-excellent antibacterial and antifungal activities against six plant pathogens. Especially, compound
possessed the most remarkable antibacterial activity against
(EC
= 2.23 μg/mL), which was significantly superior to that of compound
(EC
= 69.87 μg/mL) and the commercial agent Thiodiazole copper (EC
= 52.01 μg/mL). Meanwhile, compound
displayed the most excellent antifungal activity against
(EC
= 0.51 μg/mL), which was equivalent to that of the commercial fungicide Carbendazim (EC
= 0.57 μg/mL). The preliminary structure-activity relationship (SAR) results suggested that introducing an electron-withdrawing group at the meta-position and ortho-position of the benzene ring could endow the final structure with remarkable antibacterial and antifungal activity, respectively. The current results indicated that these compounds were capable of serving as promising lead compounds.
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