Strigolactones (SLs) are a new class of carotenoid-derived phytohormones essential for developmental processes shaping plant architecture and interactions with parasitic weeds and symbiotic ...arbuscular mycorrhizal fungi. Despite the rapid progress in elucidating the SL biosynthetic pathway, the perception and signaling mechanisms of SL remain poorly understood. Here we show that DWARF53 (D53) acts as a repressor of SL signaling and SLs induce its degradation. We found that the rice
d53
mutant, which produces an exaggerated number of tillers compared to wild type plants, is caused by a gain-of-function mutation and is insensitive to exogenous SL treatment. The
D53
gene product shares predicted features with the class I Clp ATPase proteins and can form a complex with the α/β hydrolase protein DWARF14 (D14) and the F-box protein DWARF3 (D3), two previously identified signaling components potentially responsible for SL perception. We demonstrate that, in a D14- and D3-dependent manner, SLs induce D53 degradation by the proteasome and abrogate its activity in promoting axillary bud outgrowth. Our combined genetic and biochemical data reveal that D53 acts as a repressor of the SL signaling pathway, whose hormone-induced degradation represents a key molecular link between SL perception and responses.
Carbon nanotubes (CNTs) with large length-diameter ratios and high conductivity are ideal to fabricate conductive networks in cathodes for Li ion batteries. However, good dispersion of CNTs in ...cathodes remains great challenge. Here, a CNT suspension containing an ultra-low concentration (0.2 wt%) of vertically-aligned CNTs (VACNTs) is used to construct a well-dispersed conductive network in cathodes. The VACNTs exhibit excellent dispersion stability in N-methyl pyrrolidone due to less entangling between CNTs. Significant promotion in specific capacities and low temperature performance have been achieved by adding highly-dispersed VACNTs into LiFePO4 cathodes.
•NO3-N dynamic were similar among mulching fields during the early growing season.•NO3-N concentrations in 0–40 cm were higher under biodegradable film mulching.•Corn yield and the N use efficiency ...were significantly increased by mulching.•210 kg ha−1 N-fertilizer under biodegradable film mulching is an optimal scenario.
Drip irrigation under plastic film mulching with applications of the N-fertilizer is an excellent agricultural strategy, resulting in saving irrigation water, improving N use efficiency, and increasing crop yield. However, the film residue and nitrate-nitrogen (NO3-N) losses are the leading cause of non-point pollution in agricultural fields. To promote the development of sustainable agriculture, the HYDRUS (2D/3D) model was first calibrated and then validated using experimental data from 2016 and 2017, respectively, collected in the drip-irrigated sandy field with plastic film mulching (PFM), biodegradable film mulching (BFM), and no film mulching (NFM). Additionally, the NO3-N spatial and temporal distributions, uptake, leaching, and use efficiency (NUE) under PFM, BFM, and NFM with 280 kg ha−1 of the N-fertilizer (the local recommendation) were evaluated using both observed and simulated data. These factors were also assessed under BFM with 210 (75 % of the recommended value) and 140 kg ha-1 (50 % of the recommended value) of the N-fertilizer. The results of numerical simulations were in good agreement with observations, with the RMSE, R2, and NSE during verification being 0.01-0.08 mg cm-3, 0.62-0.87, and 0.68-0.94, respectively. When the same amount of the N-fertilizer (280 kg ha−1) was applied in each treatment, there were no apparent differences in NO3-N concentrations in the soil profile, cumulative NO3-N uptake by corn (CNU), and cumulative NO3-N leaching (CNL) in the 100-cm soil depth between the BFM280 and PFM280 scenarios (the subscript indicates the amount of the N-fertilizer) during the early growing season (Day After Sowing DAS of 0–78 in 2016 and DAS of 0–92 in 2017). However, CNU and CNL were higher, and the NO3-N concentrations in the upper soil layer (0−40 cm soil layer) lower in these two scenarios than in the NFM280 scenario. The NO3-N concentrations in the topsoil layer (the 0−20 cm soil layer) in the BFM280 scenario were 3.9 % higher than in the PFM280 scenario during DAS 93–154 in 2017 due to the disintegration of the biodegradable film and 26.3 % lower during DAS 79–155 in 2016 because of intensive rainfall. Additionally, the highest NUE (50.9 kg kg-1, the average value for two years) was found when 75 % of the recommended N-fertilizer (210 kg ha−1) was applied. Therefore, an application of 210 kg ha−1 of the N-fertilizer in the BFM scenario can be recommended for sandy farmland to avoid plastic pollution, increase NUE, and effectively promote the development of sustainable agriculture.
Jasmonates are a family of plant hormones that regulate plant growth, development and responses to stress. The F-box protein CORONATINE INSENSITIVE 1 (COI1) mediates jasmonate signalling by promoting ...hormone-dependent ubiquitylation and degradation of transcriptional repressor JAZ proteins. Despite its importance, the mechanism of jasmonate perception remains unclear. Here we present structural and pharmacological data to show that the true Arabidopsis jasmonate receptor is a complex of both COI1 and JAZ. COI1 contains an open pocket that recognizes the bioactive hormone (3R,7S)-jasmonoyl-l-isoleucine (JA-Ile) with high specificity. High-affinity hormone binding requires a bipartite JAZ degron sequence consisting of a conserved α-helix for COI1 docking and a loop region to trap the hormone in its binding pocket. In addition, we identify a third critical component of the jasmonate co-receptor complex, inositol pentakisphosphate, which interacts with both COI1 and JAZ adjacent to the ligand. Our results unravel the mechanism of jasmonate perception and highlight the ability of F-box proteins to evolve as multi-component signalling hubs.
•Low GWP ternary zeotropic mixtures were applied in high-temperature heat pump.•A novel selected method of ternary zeotropic mixtures was proposed.•The selected mixtures show high potential in heat ...pump for waste heat recovery.•The mixture CO2/R600a/R1233zd(E) shows the better performance.
In this study, the novel low GWP ternary large glide temperature zeotropic mixtures were proposed to apply in the high-temperature heat pump for waste heat recovery. The ternary zeotropic mixtures were composed of two retardants (CO2 and R1233zd(E)) and one flammable, including (R600a, R290, R1270, and RE170). First, a novel method, which combines the operated pressure, glide temperature, flammability, safety, energy, and exergy efficiency, were proposed to select the proper ternary zeotropic mixture applied in the high temperature heat pump. Besides, the effect of operated temperature parameters, including the subcooling degree (Tsc), superheating degree (Tsh), dew point temperature in evaporator (Tdew,evap), and dew point temperature in condenser(Tdew,cond), on the performance of the high temperature heat pump using the selected optimal ternary zeotropic mixture was conducted further. The results show that the ternary zeotropic mixture CO2/R600a/R1233zd(E) was selected to applied in the high temperature heat pump with the mass fraction of 0.2/0.7/0.1, and the maximum heating coefficient of performance (COPh), volumetric heating capacity (qv) and exergy efficiency (ηex) are 3.22, 3017 kJ/m3 and 0.402, respectively under the selected condition. Besides, compared with the Tsc and Tsh, the Tdew,cond and Tdew,evap affect the performance notable for the selected ternary zeotropic mixture, especially for the Tdew,cond, which affect the condensation pressure significantly and should be gain more attention for the high temperature application. Among the Tdew,cond and Tdew,evap, The COPh and qv are sensitive to the Tdew,cond and the Tdew,evap, respectively. The results hope to promote the application and research of low GWP zeotropic mixtures in the high-temperature heat pump.
Vitrimer is a new class of polymeric materials which can be reprocessed to any shape while being permanently cross-linked. We designed and synthesized a catalyst-free network with ...poly(dimethylsiloxane)etherimide (PDMS-NH2), terephthalaldehyde (TA), and tri(2-aminoethyl)amine (TREA) through the condensation reaction between amino groups and aldehyde groups. As a result of the exchange reaction of the dynamic imine bond obtained, this PDMS network exhibits the nature of vitrimer-like material, which is examined by solubility and stress-relaxation experiments, and the relaxation time is as short as 64 s at 130 °C. In addition, the vitrimer-like PDMS is malleable and capable of self-healing, and the mechanical properties can be maintained even after three consecutive breaking/mold pressing cycles. Especially, besides heating, this vitrimer-like PDMS can also be recycled and reshaped at ambient temperature due to the exchange reaction of dynamic imine bond when immersed in water, which will potentially lead to green processing of the elastomers.
Brackish water has been increasingly used worldwide for irrigation to relieve crop water stress. However, crop yield reductions inevitably occur under uncontrolled irrigation with saline waters, ...especially in areas with shallow and saline groundwater. It is essential to quantify the movement of soil water and salts in a soil-plant system and to optimize irrigation patterns with brackish water to alleviate the harm of salt stress on crop growth. Therefore, a two-year cornfield experiment was carried out during 2020–2021 to evaluate differences in soil water and salt movement under different irrigation regimes: a) brackish water irrigation with high (HB), medium (MB), and low (LB) irrigation depths, and b) freshwater irrigation with medium irrigation depths (MF). Moreover, the HYDRUS (2D/3D) model was used to evaluate soil water contents (SWC), electrical conductivities of the saturation paste extract (ECe), and fluxes, distributions, and mass balances of soil water and salts for the HB, MB, LB, and MF regimes. Meanwhile, oxygen isotope (18O) was used to calibrate and verify the simulation accuracy of the HYDRUS (2D/3D) model by determining the proportion of water and salt sources in a soil-plant system.The results showed that HYDRUS (2D/3D) could precisely capture SWC and ECe under different irrigation treatments, with the root mean square error (RMSE) of 0.004–0.017 cm3 cm−3 and 0.023–0.372 dS m−1 for SWC and ECe, respectively. The highest differences in SWCs and ECe in plots under brackish water and freshwater irrigations occurred in the 0–20 cm soil layer. The stress areas in the soil profile due to water and salt stresses under MB decreased and increased by 1.8 cm2 and 2010.0 cm2, respectively, compared with MF, accounting for 0.04% and 40.2% of the root zone. However, average root water uptake (RWU) in both years under MB decreased by 1.9% compared to MF. Additionally, RWU showed a nonlinear relationship with irrigation depth when brackish water was used for irrigation. The highest RWU occurred under MB, where the average RWU in both years increased by 7.7% and 12.4% compared with HB and LB, respectively. Therefore, the MB treatment could be recommended to increase crop yield and alleviate the freshwater shortage in agricultural production. Moreover, the findings of this study improve our understanding of the mechanisms of soil water and salt movement and groundwater contributions in a system under brackish water irrigation with different irrigation depths.
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•The movements of soil water and salts under brackish water irrigation were quantified experimentally and numerically.•An oxygen isotope was used to verify the water fluxes simulated by HYDRUS (2D/3D).•Root water uptake increased nonlinearly with increased irrigation depths of brackish water.•The irrigation depth of 23 mm is an optimal irrigation depth for irrigation with brackish water.
The plant hormone auxin regulates virtually every aspect of plant growth and development. Auxin acts by binding the F-box protein transport inhibitor response 1 (TIR1) and promotes the degradation of ...the AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) transcriptional repressors. Here we show that efficient auxin binding requires assembly of an auxin co-receptor complex consisting of TIR1 and an Aux/IAA protein. Heterologous experiments in yeast and quantitative IAA binding assays using purified proteins showed that different combinations of TIR1 and Aux/IAA proteins form co-receptor complexes with a wide range of auxin-binding affinities. Auxin affinity seems to be largely determined by the Aux/IAA. As there are 6 TIR1/AUXIN SIGNALING F-BOX proteins (AFBs) and 29 Aux/IAA proteins in Arabidopsis thaliana, combinatorial interactions may result in many co-receptors with distinct auxin-sensing properties. We also demonstrate that the AFB5-Aux/IAA co-receptor selectively binds the auxinic herbicide picloram. This co-receptor system broadens the effective concentration range of the hormone and may contribute to the complexity of auxin response.
The emerging micro-nano-processing technologies have propelled significant advances in multifunctional systems that can perform multiple functions within a small volume through integration. Herein, ...we present an on-chip multifunctional system based on a 1T/2H-MoS
2
/graphene fishnet tube, where a micro-supercapacitor and a gas sensor are integrated. A hybrid three-dimensional stereo nanostructure, including MoS
2
nanosheets and graphene fishnet tubes, provides K
+
ions with a short diffusion pathway and more active sites. Owing to the large layer spacing of 1T-MoS
2
promoting fast reversible diffusion, the on-chip micro-supercapacitor exhibits excellent electrochemical properties, including an areal capacitance of 0.1 F·cm
−2
(1 mV·s
−1
). The variation in the conductivity of 2H-MoS
2
when ammonia molecules are adsorbed as derived from the first-principles calculations proves the Fermi level-changes theory. Driven by a micro-supercapacitor, the responsivity of the gas sensor can reach 55.7% at room temperature (27 °C). The multifunctional system demonstrates the possibility of achieving a two-dimensional integrated system for wearable devices and wireless sensor networks in the future.
Regulating the plastic film mulching duration was a good strategy to decrease plastic residues and to avoid the stress from low soil nitrate concentration (SNC). However, few studies focused on soil ...nitrogen dynamic under different mulching durations, especially for the impacts of soil nitrogen loss on crop yield and comprehensive benefits have not been revealed. In this study, HYDRUS (2D/3D) model was used to evaluate the differences of SNC and NO3-N leaching (NL) under no mulching (NM), mulching for the seedling stage (PMS), mulching for the elongation stage (PME), mulching for the tasseling stage (PMT), and mulching for the entire corn growth season (PMW). Additionally, a two-year (2019–2020) field experiment was carried out to measure SNC, NL, N2O, and NH3 emissions and to calibrate and validate the model accuracy. The effect of soil nitrogen loss on the comprehensive benefits under different mulching durations was further analyzed using a comprehensive multi-objective model. The results showed that HYDRUS (2D/3D) could well capture SNC dynamic under different mulching treatments, with average the normalized root mean square error of 16.5% in the validation period. There was no apparent difference in SNC, N2O emission, NH3 emission, and NL under different mulching durations in the seedling stage. However, the corresponding difference markedly increased with corn growth and development, especially in 2019. The average SNC (0–20 cm soil depth) under NM was higher by 9.2%, 25.0%, 21.2%, and 19.4% than PMS, PME, PMT, and PMW, respectively. Nitrogen emission (N2O and NH3) showed an increase trend with the shortening of mulching duration, i.e., NM>PMS>PME >PMT >PMW, while an opposite trend was found for NL. In general, PME was found to be the optimal mulching duration with the highest comprehensive evaluation score of 1782.7. Therefore, PME can be recommended to apply in this region to promote the developments of sustainable agriculture.
•Nitrogen transformation parameters in HYDRUS (2D/3D) was calibrated and validated.•Entropy method is used to evaluate the agriculture production among mulching fields.•An apparent difference in soil surface nitrate concentration among mulching duration.•N2O and NH3 emissions increased as the shortening of mulching duration.•Removing plastic film in the elongation stage is recommended for corn.
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