The multidrug and toxic compound extrusion (MATE) family is the latest class of novel secondary transporters discovered in plants. However, there is currently no comprehensive analysis of the MATE gene family in the tea plant. In this study, 68 CsMATE genes were identified from the tea plant genome using bioinformatic methods. In general, we analyzed the evolutionary relationships, intron–exon structure, distribution in chromosomes, conserved domains, and gene expression patterns in different tissues and stresses of the CsMATE gene family. The 68 CsMATEs were phylogenetically divided into four major clusters (Class I to Class IV). The CsMATE genes within the same class exhibit similar structural features, while displaying certain distinctions across different classes. Evolutionary analysis indicated that the CsMATE gene family expanded mainly through gene duplication events, in addition to proximal duplication. Through the analysis of cis-acting elements, it was found that CsMATE genes may be involved in the growth, development, and stress response. Furthermore, we observed that certain CsMATE genes could be induced to exhibit expression under abiotic stress conditions such as low temperature, high salinity (NaCl), osmotic stress (PEG), and methyl jasmonate treatment (MeJA). The findings presented herein offer a crucial theoretical foundation for elucidating the biological functions of CsMATE genes, particularly in response to abiotic stress, and furnish valuable potential genetic resources for tea plant resistance breeding.

Phosphorus (P) deficiency is a major constraint on crop productivity, and rapeseed (Brassica napus L.) is particularly sensitive to low phosphorus (LP) stress, yet the role of salicylic acid (SA) in alleviating LP stress in this crop remains poorly understood. Here, we investigated how exogenous SA alleviates LP stress in rapeseed seedlings. SA was applied at 0.1 mM and 0.2 mM under LP conditions, and its effects on plant growth, physiological traits, and transcriptomic responses were evaluated. SA treatment significantly ameliorated LP-induced growth inhibition, increased chlorophyll content and peroxidase activity, and reduced superoxide anion accumulation. RNA-seq analysis revealed that SA up-regulated the expression of phosphate transporter (PHT) family genes and activated genes involved in nitric oxide biosynthesis, flavonoid biosynthesis, glutathione metabolism, and nitrogen metabolism. These findings indicate that SA enhances LP tolerance in rapeseed through coordinated regulation of phosphorus acquisition, antioxidant defense, and key metabolic pathways, highlighting the potential of exogenous SA as an approach that could be further explored to improve phosphorus use efficiency under phosphorus-limited conditions in controlled environments, with field validation still needed.