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Zygophyllum xanthoxylum is a salt‐accumulating xerophytic species with excellent adaptability to adverse environments. Previous studies demonstrated that Z. xanthoxylum absorbs a great quantity of Na⁺ as an osmoregulatory substance under arid conditions. To investigate the nutritional status of Z. xanthoxylum in comparison with a typical glycophyte, Arabidopsis thaliana, seedlings were exposed to NaCl (50 mM for Z. xanthoxylum and 5 mM for A. thaliana), osmotic stress (–0.5 MPa), and osmotic stress combined with the NaCl treatment. Compared to the control, NaCl treatment or osmotic stress significantly increased Na⁺ concentration in leaves and roots of Z. xanthoxylum, but not of A. thaliana. Under osmotic stress, the addition of NaCl significantly increased Na⁺ concentration in leaves and roots of Z. xanthoxylum, resulting in improved biomass and tissue water content. However, such changes were not observed in A. thaliana. Compared to the control, K⁺ concentrations in leaves and roots remained unchanged in Z. xanthoxylum when exposed to osmotic stress, with or without additional 50 mM NaCl. In contrast, significant reductions in shoot K⁺ concentrations of A. thaliana were observed under osmotic stress alone or when combined with 5 mM NaCl. Moreover, NaCl alone or when combined with osmotic stress enhanced the accumulation of N, P, Fe, Si, Ca²⁺, and Mg²⁺ in Z. xanthoxylum, but did not cause such nutritional changes in A. thaliana. Compared to the glycophyte A. thaliana, Z. xanthoxylum could accumulate Na⁺ and maintain the stability of nutritional status at a relatively constant level to cope with drought stress.

The editorial office would like to draw reader's attention to an error occurring in the publication by Wang et al. · Under drought conditions NaCl improves the nutritional status of the xerophyte Zygophyllum xanthoxylum but not of the glycophyte Arabidopsis thaliana · pp. 597–606 · Volume 182 · Number 4 · August 2019 that we like to apologize for. 1. Figure : (Figure presented.) Fe concentration of Z. xanthoxylum (a) and A. thaliana (b) under different treatments (C, O, S, O+S) for 72 h. Control (C), osmotic stress (O) (–0.5 MPa osmotic potential induced by sorbitol), salt treatment (S) (50 mM NaCl for Z. xanthoxylum and 5 mM NaCl for A. thaliana), and osmotic stress with corresponding concentrations of NaCl (O+S) (total osmotic potential –0.5 MPa). Values are means ± SE (n = 8) and bars represent SE. Columns labelled different letters indicate significant differences at P < 5% (Duncan's test). 2. Figure : (Figure presented.) Si concentration of Z. xanthoxylum (a) and A. thaliana (b) under different treatments (C, O, S, O+S) for 72 h. Control (C), osmotic stress (O) (–0.5 MPa osmotic potential induced by sorbitol), salt treatment (S) (50 mM NaCl for Z. xanthoxylum and 5 mM NaCl for A. thaliana), and osmotic stress with corresponding concentrations of NaCl (O+S) (total osmotic potential –0.5 MPa). Values are means ± SE (n = 8) and bars represent SE. Columns labelled different letters indicate significant differences at P < 5% (Duncan's test). These changes do not affect the conclusions mentioned in the paper.

UNLABELLED PREMISE OF THE STUDY Food crops of tropical origins, such as rice, are often cultivated in areas with suboptimal temperature regimes. The rice phytochrome B-deficient mutant (phyB) is tolerant of chilling temperatures compared with the wild type (WT) under low irradiance, and unsaturated fatty acids (USFAs) of membrane lipids have been shown to play an important role in chilling resistance. However, the relationship between phytochrome B and membrane lipids has not been empirically investigated. • METHODS We assessed various photosynthesis indexes in phyB and WT rice: chlorophyll content, maximal photochemical efficiency (Fv/Fm) of photosystem II (PSII), the quantum yield of PSII electron transport (ΦPSII), the percentage of oxidizable P700 (P700), nonphotochemical quenching (NPQ), and the de-epoxidized ratio of xanthophyll cycle (A+Z)/(V+A+Z). We also analyzed the ultrastructure and fatty acid desaturases (FADs) and glycerol-3-phosphate acyltransferase (GPAT) genes of the chloroplasts using transmission electron microscopy and real-time PCR. • RESULTS After a chilling treatment of 24 h, chloroplast damage and USFA content reduction were more severe in the WT than in the phyB mutant. Genes involved in the synthesis of USFAs in membranes such as FADs and GPAT were more stable in phyB than in WT. Chlorophyll content, Fv/Fm, ΦPSII, and P700 decreased more slowly under chilling stress and recovered more rapidly under optimal conditions in phyB than in WT. The (A+Z)/(V+A+Z) and NPQ increased more rapidly in phyB than in the WT after 24 h of chilling treatment. • CONCLUSIONS Phytochrome B deficiency in rice with more stabilized chloroplast structure and higher USFA content in membrane lipids could alleviate chilling-induced photoinhibition.

The recretohalophyte with specialized salt-secreting structures including salt glands and salt bladders can secrete salt from their bodies and easily adapt themselves to many kinds of salt habitats. Salt glands and salt bladders, arose from dermatogen cells, are excretory organs specially adapted for dealing with ionic homeostasis in the cells of recretohalophytes. The main function of salt glands or salt bladders is to secrete excess ions that invade the plant. The structures of salt glands or salt bladders differ among plant species. In addition to structural differences, salt glands also differ in their secretion abilities. In this review, we mainly focus on recent progress in the mechanism of salt excretion of salt glands and salt bladders, and in particular, emphasize the vesicle-mediated secretion systems from the vacuole to the plasmalemma and the possibly involved membrane-bound translocating proteins for salt secretion of plant gland secretory cell.

Ascorbate–glutathione (AsA–GSH) cycle is an important component of the scavenging system for reactive oxygen compounds in plants. The member of this pathway involves the antioxidants: AsA, GSH and the antioxidatnt enzymes such as ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAsAR), dehydroascorbate reductase (DAsAR) and glutathione reductase (GR). APX and GR are the key enzymes of the AsA–GSH cycle. APX utilizes AsA as the electron donor reducing H2O2 to water, and prevents the accumulation of a toxic level of H2O2 in photosynthetic organisms under stress conditions. GR converts oxidized glutathione (GSSG) to GSH using NAD(P)H as an electron donor. And thus a highly ratio of GSH/GSSG and AsA/DAsA is maintained at the intracellular level by this reaction during oxidative stress. In general, APX and GR activity have been shown to increase in various plant species under different stress conditions. Transgenic plants showed that APX and GR play an important role in providing resistance to oxidative stress caused by diferent stressors such as paraquat, methyl viologen, ozone, drought, heavy metals, high light, salinity, and chilling. In this review, recent progress in research on APX, GR and stress tolerance will be discussed.

Salt stress can induce ionic stress and osmotic stress in plant cells. A direct result of these primary effects is the enhanced accumulation of reactive oxygen species (ROS) that are harmful to plant cells at high concentrations. To cope with the oxidative stress resulting from the ROS, higher plants have developed a complex scavenging system including enzymatic and non-enzymatic ( antioxidants) system. In plant cells, specific ROS producing and scavenging systems are found in different organelles such as chloroplasts, mitochondria, and peroxisomes; and the ROS-scavenging pathways from different cellular compartments are coordinated. Relatively low levels of ROS can be used for signaling molecules to control abiotic stress responses. Coordinated work of ROS-scavenging pathways from different