The selenium (Se) content in human hair is useful as an indicator of human Se intake and status. In this regard, when measuring the hair Se concentrations in Chinese inhabitants across northeast to southeast China, the results indicated that generally 84% of all residents have normal hair Se content. Between the sexes, the average hair Se content of males was higher than that of females, irrespective of districts. When comparing geographical regions, the average hair Se content of southern residents was greater than that of northern residents, regardless of gender. Historically, the overall hair Se content of today’s inhabitants decreased between 24% and 46% when compared with the inhabitants living in the same geographic region 20 years ago. The decrease of hair Se content may be related to the overall decrease of grain consumption and the lower Se content in the staple food rice.

An electrochemical voltammogram recording method for plant variety identification is proposed. Electrochemical voltammograms of Vistula, Andromeda, Danuta, Armandii ‘Apple Blossom,’ Proteus, Hagley Hybrid, Violet Elizabeth, Kiri Te Kanawa, Regina, and Veronica’s Choice were recorded using leaf extracts with two solvents under buffer solutions. The voltametric data recorded under different conditions were derived as scatter plots, 2D density patterns, and hot maps for variety identification. In addition, the voltametric data were further used for genetic relationship studies. The dendrogram deduced from the voltammograms was used as evidence for relationship study. The dendrogram deduced from voltametric data suggested the Andromeda, Danuta, Proteus, Regina, and Hagley Hybrid were closely related, while Violet Elizabeth and Veronica’s Choice were closely related. In addition, Vistula and Armandii ‘Apple Blossom’ could be considered outliers among the varieties.

Lagerstroemia indica is an important woody ornamental plant worldwide. However, the application of many technologies, such as transgenic breeding and genome editing, has been severely hampered due to the lack of efficient calli induction and regeneration technology. Here, we discussed a reliable and efficient calli induction and regeneration protocol using whole-leaf explants. This protocol’s effectiveness for the calli induction and regeneration systems in crape myrtle were up to 70.33% and 44.33%, respectively. Next, an efficient and stable Agrobacterium-mediated genetic transformation system was created from leaf calli, and the green fluorescent protein (GFP) was able to detect up to 90% of its positive frequency. Meanwhile, two positive lines’ transfer DNA insertion sites and directions were identified using whole genome sequencing. LiMYB75, a novel R2R3-MYB transcription factor, was identified and transferred to the L. indica genome to enhance the leaf calli regeneration frequency. Surprisingly, overexpressing LiMYB75 increased the frequency of calli regeneration in the leaf by 1.27 times and the number of regenerated plantlets per callus by 4.00 times compared to the wild type, by regulating the expression levels of genes involved in callus formation, such as SHOOT MERISTEMLESS (STM). Overall, our findings revealed a simple, reliable, and highly efficient transformation approach and identified the desirable candidate gene LiMYB75, which improves L. indica’s calli regeneration efficiency.

Catalpa bungei is an economically important tree with high-quality wood, which is highly ornamentally valuable in China. Salinity is one of the major constraints restricting the growth of the C. bungei. However, the molecular mechanism underlying the salt stress response remains unknown in C. bungei. In our previous study, a novel WRKY transcription factor gene CbWRKY27 was isolated using association mapping based on the transcriptome database of Catalpa Yuqiu1. In this study, CbWRKY27 was found to function as a transcriptional activator in the nucleus. The transcription of CbWRKY27 was inhibited under salt stress and reactive oxygen species (ROS) but was induced after abscisic acid (ABA) treatment. CbWRKY27-overexpression plants showed decreased tolerance to salt stress compared to wild type while enhancing sensitivity to ABA-regulated lateral root length. Quantitative real-time PCR (qPCR) studies showed that the transcript levels of the ABA biosynthesis gene (NCED3), signaling genes (ABI3 and ABI5), and responsive genes (RD29B and RD22) were greatly increased in CbWRKY27-overexpression plants under salt stress. Under salt treatment, CbWRKY27-overexpression plants disturbed ROS homeostasis by repressing antioxidant enzymes and enhancing the production of O₂⁻ and H₂O₂ through down-regulation of ROS-scavenging-related genes (APX, SOD, and PER57). In summary, these results indicate that CbWRKY27 negatively regulates salt tolerance in C. bungei.

Background: The yellow-leaf gl1 mutant of Lagerstroemia indica exhibits an altered phenylpropanoid metabolism pathway compared to wild-type (WT). However, details on the metabolites associated with leaf color variation, including color-specific metabolites with bioactive constituents, are not fully understood. Methods: Chemical and metabolomics approaches were used to compare metabolite composition and antioxidant capacity between the gl1 mutant and WT leaves. Results: The mutant exhibited an irregular xylem structure with a significantly lower phenolic polymer lignin content and higher soluble phenolic compounds. Untargeted metabolomics analysis identified phenolic compounds, particularly lignans, as key differential metabolites between gl1 and WT, with a significant increase in the mutant. The neolignan derivative balanophonin-4-O-D-glu was identified as a characteristic metabolite in the gl1 mutant. The soluble phenolic compounds of the gl1 mutant exhibited higher FRAP, ABTS, DPPH, and hydroxyl radical scavenging activity than in WT. Correlation analysis showed a positive relationship between antioxidant capacity and phenolic compounds in L. indica. Conclusions: Metabolites associated with leaf color variation in the L. indica yellow-leaf gl1 mutant demonstrated high antioxidant capacity, particularly in scavenging hydroxyl radicals.