Euhalophytes, such as Suaeda salsa, are ideal candidates to remediate heavy metal-polluted saline soils. However, the metal tolerance ability of dimorphic seeds and subsequent seedlings is largely unknown. This study investigated the tolerance of S. salsa seeds to different concentrations of Cu²⁺ (0–300 mM) and Zn²⁺ (0–300 mM) during germination and seedling growth stages. Results showed that dimorphic seeds of S. salsa had high metal tolerance during germination, and even germinated under 300 mM Cu and Zn treatments. However, seedling growth was more sensitive to metal solutions and radicle growth was almost completely inhibited by Cu at 10 mM, and by Zn at 50 mM. Germinating seeds and seedlings of S. salsa had a higher metal toxicity threshold of Zn than that of Cu. In all indexes, indexes of radicle were the most sensitive and effective indicator of metal tolerance. Seeds of S. salsa germinated successfully and seedlings survived under high Zn and Cu stress. The results suggest that S. salsa could be sown directly in heavy metal-contaminated soils for phytoremediation.

Seed germination is a crucial stage in the life cycle of annuals in arid, saline regions and is particularly vulnerable to abiotic stresses. Peganum harmala, a valuable medicinal plant, has limited research on its seed germination response to different environmental stresses in the arid, saline regions of Central Asia. To investigate this, we studied the effects of various temperature regimes (ranging from 20/5 to 35/20 °C), light exposure (12 hours light/12 hours dark and continuous dark), seven levels of polyethylene glycol (PEG-6000) concentration (ranging from 0–30%), and four types of salinity (ranging from 0–600 mmol L⁻¹). Our findings show that photoperiod and temperature significantly influence germination. Optimal temperature range for seed germination was observed at 30/15 °C, with simulated critical and limit values of drought tolerance being highest (17.30% and 24.98%). However, higher temperatures (35/20 °C) and lower temperatures (20/5 °C) reduced the critical and limit values of drought tolerance. Additionally, the type and concentration of salinity had a significant effect on the seed germination, shoot, and root lengths of P. harmala. Regression analysis indicated that the critical values of NaCl, Na₂SO₄, NaHCO₃, and Na₂CO₃ tolerance during germination were 178 mmol L⁻¹, 101 mmol L⁻¹, 106 mmol L⁻¹, and 54 mmol L⁻¹, respectively. Salinity inhibition on seed germination followed the order: NaCl < NaHCO₃ < Na₂SO₄ < Na₂CO₃. Moreover, NaCl, Na₂SO₄, NaHCO₃, and Na₂CO₃ significantly inhibited the growth of P. harmala seedlings in both shoots and roots. Our study demonstrates the sensitivity of P. harmala to environmental factors such as light, temperature, drought, and salinity. The study provides valuable information on the germination ecology of P. harmala under diverse ecological scenarios, which can be useful in developing efficient propagation and utilization of this medicinal plant.

Apocynum pictum (A. pictum) honey is rich in effective ingredients including flavonoids, terpenes, and alkaloids that are beneficial to human health. In this study, widely targeted metabolomics were used to detect the plant-derived secondary metabolites of the same batch of A. pictum honey from 2022 to 2024, in order to explore whether storage time changes the quality of A. pictum honey, especially the content of plant-derived secondary metabolites with important health benefits. The results showed that storage time had no significant effect on the content of sugars, proteins, and other major components in A. pictum honey. At the same time, we also found that although storage time had an impact on the content of some secondary metabolites such as flavonoids in A. pictum honey, the changes in the content of the characteristic active ingredient, hyperoside, in A. pictum honey were not significant. These findings suggest that storage time has a minimal impact on the quality of A. pictum honey. This study provides a theoretical basis for the rational storage of A. pictum honey.

Apocynum pictum and Apocynum venetum are two medicinal important halophytes' plants from Xinjiang, China. However, honey derived from these plants, remains unexplored. This study investigated the physicochemical properties, essential elements, enzymatic activity, and metabolomic profiles of both types of honeys. This study identified A. pictum honey significantly higher peroxidase (POD) activity (19.2 ± 1.1 U/g vs. 7.5 ± 0.3 U/g), adenine content (17.5 ± 0.1 mg/g vs. 6.2 ± 0.1 mg/g), and protein levels (13.0 ± 0.5 mg/g vs. 11.2 ± 0.4 mg/g) compared to A. venetum honey. Mineral analysis showed potassium (76.5 ± 1.2 mg/L, 2.8 ± 0.1, 46.0 ± 1.5 mg/L), magnesium, and zinc in A. pictum honey, aligning with its adaptation to arid conditions. Total 735 differentially accumulated metabolites (DAMs), such as flavonoids (diosmetin, chrysin), phenolic acids (homogentisate), and alkaloids (tryptamine), linked to antioxidant, anti-inflammatory, and anticancer properties. Thus, approved A. pictum honey superior nutritional and therapeutic values.

Water conditions directly affect plant growth and thus modify reproduction allocation. However, little is known about the transgenerational effects of water conditions on xerophytes. The desert annual Atriplex aucheri produces three types of seeds (A: dormant, ebracteate black seeds; B: dormant, bracteolate black seeds; C: non-dormant, bracteolate brown seeds) on a single plant. The aim of this study was to investigate the effects of low/high water treatment (thereafter progeny water treatment) on aboveground biomass, C:N stoichiometry, and offspring seed characteristics of A. aucheri grown from brown seeds whose mother plants were under low/high water treatment (thereafter maternal water treatment). Progeny water only affected shoot dry weight and seed allocation of type A. Under low progeny water treatment, plants from parents with low maternal water treatment had the lowest biomass. Maternal water did not significantly influence the C and N content, however high maternal water increased the C:N ratio. Maternal water treatment did not significantly affect seed number. However, plants under low maternal and progeny water treatments had the lowest weight for type B seeds. When progeny plants were under low water treatment, seed allocation of type A, type B, and total seed allocation of plants under high maternal water were significantly lower than those of plants under low maternal water. These results indicate that water conditions during the maternal generation can dramatically contribute to progeny seed variation, but the transgenerational effects depend on the water conditions of progeny plants.

Apocynum venetum L. is an economically valuable plant with tolerance to drought and salinity. Its leaves are utilized in tea production and pharmaceuticals, while the stem bark serves as a high-quality fiber material. To gain insights into the gene expression patterns of A. venetum using quantitative real-time PCR (qRT-PCR), it is crucial to identify appropriate reference genes. This study selected nine candidate genes, including α-tubulin (TUA), β-tubulin (TUB), actin (ACT), cyclophilin (CYP), elongation factor-1α (EF-1α), the B family of regulatory subunits of protein phosphatase (PPP2R2, PPP2R3, and PPP2R5), and phosphoglycerate kinase (PGK), to determine the most appropriate reference genes in the leaf, stem, and root tissues of A. venetum. A comprehensive ranking by geNorm, NormFinder, BestKeeper, and RefFinder software and Venn diagrams was used to screen more stable reference genes in different tissues. The two most stable reference genes were CYP and TUA in leaves, PGK and PPP2R3 in stems, and TUA and EF-1α in roots, respectively. The relative expression values of the four genes involved in proline metabolism under polyethylene glycol treatment were used to validate the screened reference genes, and they exhibited highly stable expression levels. These findings represent the first set of stable reference genes for future gene expression studies in A. venetum. They significantly contribute to enhancing the accuracy and reliability of gene expression analyses in this economically important plant species.