Introduction: Soil salinization poses a significant challenge to plant growth and vitality. Plants like Tamarix ramosissima Ledeb (T. ramosissima), which are halophytes, are often integrated into planting schemes tailored for saline environments. Yet, the role of WRKY transcription factors in T. ramosissima, especially under sodium chloride (NaCl) stress mitigated by exogenous K⁺ application, is not well-understood. This research endeavors to bridge this knowledge gap.Methods: Using Pfam protein domain prediction and physicochemical property analysis, we delved into the WRKY genes in T. ramosissima roots that are implicated in counteracting NaCl stress when aided by exogenous K⁺ applications. By observing shifts in the expression levels of WRKY genes annotated to the KEGG pathway under NaCl stress at 0, 48, and 168 h, we aimed to identify potential key WRKY genes.Results: We found that the expression of 56 WRKY genes in T. ramosissima roots responded to exogenous K⁺ application during NaCl stress at the indicated time points. Particularly, the expression levels of these genes were primarily upregulated within 168 h. From these, 10 WRKY genes were found to be relevant in the KEGG pathways. Moreover, six genes, namely Unigene0024962, Unigene0024963, Unigene0010090, Unigene0007135, Unigene0070215, and Unigene0077293, were annotated to the Plant-pathogen interaction pathway or the MAPK signaling pathway in plants. These genes exhibited dynamic expression regulation at 48 h with the application of exogenous K⁺ under NaCl stress.Discussion: Our research highlights that WRKY transcription factors can modulate the activation or inhibition of related genes during NaCl stress with the application of exogenous K⁺. This regulation enhances the plant’s adaptability to saline environments and mitigates the damage induced by NaCl. These findings provide valuable gene resources for future salt-tolerant Tamarix breeding and expand our understanding of the molecular mechanisms of WRKY transcription factors in alleviating NaCl toxicity.

NaCl stress adversely affects plant growth. Tamarix ramosissima Ledeb (T. ramosissima), a halophyte, thrives in saline-alkali areas. Myo-inositol, a lipid-soluble compound, is crucial for stress response, but its role in mitigating NaCl damage remains underexplored. We analyzed transcriptome sequencing and metabolites in T. ramosissima roots under NaCl stress at various intervals (0 h, 48 h, and 168 h). We identified ten Myo-inositol oxygenase-related genes. Nine of these genes, linked to metabolic pathways involving Myo-inositol, showed differential expression. Myo-inositol accumulation increased over time, suggesting its role as an osmotic regulator and reactive oxygen species (ROS) scavenger. This accumulation likely shields T. ramosissima from NaCl-induced osmotic and oxidative damage. Notably, Unigene0002140 and Unigene0095980, associated with Myo-inositol oxygenase, appear to regulate Myo-inositol accumulation and correlate significantly with its levels. We hypothesize they are key genes in controlling Myo-inositol levels, warranting further study. This research illuminates the role of Myo-inositol oxygenase-related genes in T. ramosissima roots combating NaCl stress, offering insights for selecting salt-tolerant tree species.

The biodiversity and activity of microorganisms are crucial for litter decomposition, but how litter traits at different stages of decomposition drive changes in microbial communities has yet to be thoroughly explored. In the typical alpine hilly area of the Qinghai–Tibet Plateau, three types of litter at different decomposition stages were selected under a natural Picea crassifolia (Picea crassifolia Kom.) forest: undecomposed (A-1), partially decomposed (A-2), and fully decomposed (A-3). By measuring physicochemical indicators, microbial diversity, and the composition of the litter at different decomposition stages, this study investigates the community changes and responses of bacteria to litter characteristic changes at different decomposition levels. The results show that with the increase in decomposition level, bacterial diversity increases, community structure changes, and network complexity gradually increases, while the changes in fungal communities are insignificant. Structural equation modeling indicates that the first principal component (PC1) of litter properties is significantly negatively correlated with bacterial diversity and positively correlated with bacterial community composition. There is no significant correlation between fungal diversity and community composition, indicating a closer relationship between bacteria and litter characteristics than fungi. In summary, with an increase in litter decomposition level, the diversity and network complexity of bacterial and fungal communities will significantly increase, which is related to the changes in various litter characteristics. This study provides a scientific basis for the regulatory mechanism of litter decomposition and turnover in the alpine hilly area of the Qinghai–Tibet Plateau, specifically in Picea crassifolia forests.

Liquidambar formosana Hance is renowned for its rich leaf color and possesses notable advantages, such as robust adaptability, strong resistance to diseases and pests, and rapid growth, making it a preferred choice for urban greening and carbon sequestration forest initiatives. The completion of whole-genome sequencing of L. formosana has spurred an increased interest in exploring the molecular mechanisms underlying seasonal changes in leaf color, marking a significant focus in L. formosana breeding research. However, there is currently a lack of stable reference genes suitable for analyzing the expression patterns of functional genes in L. formosana exhibiting varying leaf colors. This study selected five L. formosana varieties with significant differences in leaf colors. Through the RT-qPCR analysis, and evaluation using BestKeeper, geNorm, NormFinder, Delta Ct, and RefFinder, the expression stability of 14 candidate reference genes was examined. Consequently, two reference genes (LifEF1-α and LifACT) with stable expression, suitable for RT-qPCR of L. formosana with diverse leaf colors, were identified. The stability of these selected reference genes was further validated by examining the LifbHLH137 gene, which promoted the biosynthesis of anthocyanins. This advancement facilitated molecular biology and genetic breeding investigations of L. formosana, providing essential data for the precise quantification of functional genes associated with leaf color variation.

Salt stress is a significant environmental factor affecting plant growth and development, with NaCl stress being one of the most common types of salt stress. The halophyte, Tamarix ramosissima Ledeb (T. ramosissima), is frequently utilized for the afforestation of saline-alkali soils. Indeed, there has been limited research and reports by experts and scholars on the regulatory mechanisms of basic leucine zipper (bZIP) genes in T. ramosissima when treated with exogenous potassium (K⁺) to alleviate the effects of NaCl stress. This study focused on the bZIP genes in T. ramosissima roots under NaCl stress with additional KCl applied. We identified key candidate genes and metabolic pathways related to bZIP and validated them through quantitative real-time PCR (qRT-PCR). The results revealed that under NaCl stress with additional KCl applied treatments at 0 h, 48 h, and 168 h, based on Pfam protein domain prediction and physicochemical property analysis, we identified 20 related bZIP genes. Notably, four bZIP genes (bZIP_2, bZIP_6, bZIP_16, and bZIP_18) were labeled with the plant hormone signal transduction pathway, showing a predominant up-regulation in expression levels. The results suggest that these genes may mediate multiple physiological pathways under NaCl stress with additional KCl applied at 48 h and 168 h, enhancing signal transduction, reducing the accumulation of ROS, and decreasing oxidative damage, thereby enhancing the tolerance of T. ramosissima to NaCl stress. This study provides gene resources and a theoretical basis for further breeding of salt-tolerant Tamarix species and the involvement of bZIP transcription factors in mitigating NaCl toxicity.

Salt stress significantly impacts plant growth, and Tamarix ramosissima Ledeb is utilized for afforestation in China’s saline–alkali regions. Trehalose, an osmoregulatory compound, enhances plant tolerance to salt stress by stabilizing cell membranes and regulating oxidative states and ion distribution. However, its role in mitigating NaCl-induced damage in Tamarix species remains understudied. In this study, root samples of T. ramosissima were exposed to NaCl stress with exogenous K⁺ at 0 h, 48 h, and 168 h. Analyses revealed that soluble sugar content increased over time, especially in the 200 mM NaCl + 10 mM KCl treatment at 168 h. Transcriptome sequencing identified 19 trehalose-related genes involved in metabolic and sucrose pathways, with Unigene0015746 notably enhancing D-Glucose 6-phosphate accumulation, a key precursor for trehalose synthesis. This gene emerged as a crucial candidate for further research. The transcriptome data were validated using qRT-PCR. Overall, the study elucidates the molecular mechanisms of trehalose-related genes in T. ramosissima under salt stress with exogenous K⁺, providing valuable genetic resources for breeding salt-tolerant tree species.