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In southern China, the fresh shoots of rape are used as a high-quality seasonal vegetable owing to their pleasant taste. In this study, we investigated the taste and quality of fresh shoots of Fanmingyoutai, which was derived from WH23 by 60Co mutation. WH23 was used as a control (CK). Physiological indexes, transcriptome analyses, and metabolomics analyses between Fanmingyoutai and CK were studied and the related key differential genes were identified. The results showed that the glucosinolate content of Fanmingyoutai seeds was 51.14% lower than that of CK, and the contents of soluble sugar and vitamin C in the fresh shoots of Fanmingyoutai were 2.1 times and 1.4 times higher, respectively, than CK. Using transcriptome analyses, we identified that the differential genes were involved in glycan biosynthesis and metabolism, energy metabolism, carbohydrate metabolism, and the metabolism of cofactors and vitamins. Metabolomics analyses demonstrated that the contents of sucrose and D-fructose in the fresh shoots of Fanmingyoutai were 1.22 times and 1.15 times higher, respectively, than those in CK. Using qRT-PCR analyses, the expression of SWEET17, STP5, and GSL in the fresh shoots and leaves of Fanmingyoutai was two times higher than that in CK. SWEET17 (involved in sugar production and transport), STP5 (involved in monosaccharide transport), and GSL (involved in glucosinolate accumulation) may be the key functional genes. We concluded that the low glucosinolate content and high sucrose and D-fructose contents may be the main factors affecting the taste of fresh shoots of Fanmingyoutai and CK; SWEET17, STP5, and GSL may be the key related genes. This research provides a reference for the breeding and molecular mechanisms of new edible rape varieties. [ABSTRACT FROM AUTHOR]

SUMMARY: Nitrogen (N) is one of the most essential mineral elements for plants. Brassinosteroids (BRs) play key roles in plant growth and development. Emerging evidence indicates that BRs participate in the responses to nitrate deficiency. However, the precise molecular mechanism underlying the BR signaling pathway in regulating nitrate deficiency remains largely unknown. The transcription factor BES1 regulates the expression of many genes in response to BRs. Root length, nitrate uptake and N concentration of bes1‐D mutants were higher than those of wild‐type under nitrate deficiency. BES1 levels strongly increased under low nitrate conditions, especially in the non‐phosphorylated (active) form. Furthermore, BES1 directly bound to the promoters of NRT2.1 and NRT2.2 to promote their expression under nitrate deficiency. Taken together, BES1 is a key mediator that links BR signaling under nitrate deficiency by modulating high affinity nitrate transporters in plants. Significance Statement: The accumulation of BES1 in the non‐phosphorylated state under low nitrogen conditions directly promotes their transcription by binding to the promoters of NRT2.1 and NRT2.2, thereby enhancing the uptake of NO3− in roots and improving the utilization efficiency of plants to nitrogen. The present study provides direct evidence that brassinosteroid signals are directly involved in the regulation of nitrogen uptake and nitrogen transporters. [ABSTRACT FROM AUTHOR]

Summary: Cadmium (Cd) is a toxic heavy element for plant growth and development, and plants have evolved many strategies to cope with Cd stress. However, the mechanisms how plants sense Cd stress and regulate the function of transporters remain very rudimentary.Here, we found that Cd stress induces obvious Ca2+ signals in Arabidopsis roots. Furthermore, we identified the calcium‐dependent protein kinases CPK21 and CPK23 that interacted with the Cd transporter NRAMP6 through a variety of protein interaction techniques.Then, we confirmed that the cpk21 23 double mutants significantly enhanced the sensitive phenotype of cpk23 single mutant under Cd stress, while the overexpression and continuous activation of CPK21 and CPK23 enhanced plants tolerance to Cd stress. Multiple biochemical and physiological analyses in yeast and plants demonstrated that CPK21/23 phosphorylate NRAMP6 primarily at Ser489 and Thr505 to inhibit the Cd transport activity of NRAMP6, thereby improving the Cd tolerance of plants.Taken together, we found a plasma membrane‐associated calcium signaling that modulates Cd tolerance. These results provide new insights into the molecular breeding of crop tolerance to Cd stress. [ABSTRACT FROM AUTHOR]

The rare-earth (RE)-based magnetic solids with large magneto-caloric effect (MCE) have been well investigated recently due to their potential applications in the field of environmentally friendly cryogenic magnetic refrigeration (MR). Herein, two polycrystalline RE-based REFe2Si2 (RE = Dy and Tb) intermetallic compounds have been prepared by an arc-melting way and determined with regard to the structural and magnetic phase transition (MPT) properties as well as the MCE and magneto-caloric performance. Both of the present REFe2Si2 compounds at room temperature are crystallized in a ThCr2Si2-type structure and undergo a first-ordered MPT from antiferromagnetic to paramagnetic state around the Néel temperature (TN) of ~ 4.05 K for DyFe2Si2 and ~ 6.25 K for TbFe2Si2, respectively. Large cryogenic MC effect together with excellent MC performance have been realized in DyFe2Si2 compound. The MC parameters with magnetic field change at 0–5 T of the maximum magnetic entropy changes and the refrigerant capacity/relative cooling power were found to be 16.08 J/kgK and 318.5/403.3 J/kg for DyFe2Si2 and to be 9.88 J/kgK and 105.9/140.8 J/kg for TbFe2Si2, respectively. [ABSTRACT FROM AUTHOR]

Two rare earth (RE)-based ternary intermetallic compounds, PrCu2Ge2 and NdCu2Ge2, have been synthesized and investigated with respect to the structure, magnetic phase transition and magnetocaloric (MC) properties. Both of the RECu2Ge2 compounds are found to be crystallized in the layered ThCr2Si2-type structure and reveal paramagnetic-to-antiferromagnetic transition at low temperature. Large reversible MC effects have been found and the maximum values of magnetic isothermal entropy change (− ΔSMmax) with the magnetic field change (ΔH) of 0–7 T are evaluated to be 5.36 J/kg K and 5.04 J/kg K for PrCu2Ge2 and NdCu2Ge2 compounds, respectively. [ABSTRACT FROM AUTHOR]

This study focuses on a black micro‐arc oxidation ceramic coating prepared on the surface of magnesium alloy by the technology of micro‐arc oxidation in the electrolyte containing F– and Fe3+ as well as its mechanism of F– and Fe3+. It needs coatings to experience detail analyses on their thickness, roughness, corrosion resistance, thermal control property, valence states of elements, phase composition, and morphology of coatings, respectively, through coating thickness gauge, roughness tester, electrochemical workstation, AE radiometer, X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), scanning electron microscope (SEM), and energy‐dispersive X‐ray spectroscopy (EDS). Results showed that with the help of F– in electrolyte, Fe3+ can be complexed and MgF2 can be obtained in the coating, which reduces the pores on the surface of micro‐arc oxidation coating. In addition, Fe3+ in the electrolyte contributes to the preparation of Fe2O3 and Fe3O4 in the coating, which can blacken the surface of the coating. Both F– and Fe3+ benefit to improve the corrosion resistance and thermal control performance of micro‐arc oxidation coating. There is higher iron oxide in the outer layer but higher fluoride in the inner layer of the coating. [ABSTRACT FROM AUTHOR]