Background: Zoysia japonica is an important warm-season turfgrass used worldwide. Although the draft genome sequence and a vast amount of next-generation sequencing data have been published, the current genome annotation and complete mRNA structure remain incomplete. Therefore, to analyze the full-length transcriptome of Z. japonica, we used the PacBio single-molecule long-read sequencing method in this study. Results: First, we generated 37,056 high-confidence non-redundant transcripts from 16,005 gene loci. Next, 32,948 novel transcripts, 913 novel gene loci, 8035 transcription factors, 89 long non-coding RNAs, and 254 fusion transcripts were identified. Furthermore, 15,675 alternative splicing events and 5325 alternative polyadenylation sites were detected. In addition, using bioinformatics analysis, the underlying transcriptional mechanism of senescence was explored based on the revised reference transcriptome. Conclusion: This study provides a full-length reference transcriptome of Z. japonica using PacBio single-molecule long-read sequencing for the first time. These results contribute to our knowledge of the transcriptome and improve the knowledge of the reference genome of Z. japonica. This will also facilitate genetic engineering projects using Z. japonica.

In this article, we propose a 3-dimensional graphical representation of protein sequences based on 10 physicochemical properties of 20 amino acids and the BLOSUM62 matrix. It contains evolutionary information and provides intuitive visualization. To further analyze the similarity of proteins, we extract a specific vector from the graphical representation curve. The vector is used to calculate the similarity distance between 2 protein sequences. To prove the effectiveness of our approach, we apply it to 3 real data sets. The results are consistent with the known evolution fact and show that our method is effective in phylogenetic analysis.

Drought, a pervasive global challenge, significantly hampers plant growth and crop yields, with drought stress being a primary inhibitor. Among resilient species, Buchloe dactyloides, a warm-season and dioecious turfgrass, stands out for its strong drought resistance and minimal maintenance requirements, making it a favored choice in ecological management and landscaping. However, there is limited research on the physiological and molecular differences in drought resistance between male and female B. dactyloides. To decipher the transcriptional regulation dynamics of these sexes in response to drought, RNA-sequencing analysis was conducted using the ‘Texoka’ cultivar as a model. A 14-day natural drought treatment, followed by a 7-day rewatering period, was applied. Notably, distinct physiological responses emerged between genders during and post-drought, accompanied by a more pronounced differential expression of genes (DEGs) in females compared to males. Further, KEGG and GO enrichment analysis revealed different DEGs enrichment pathways of B. dactyloides in response to drought stress. Analysis of the biosynthesis and signaling transduction pathways showed that drought stress significantly enhanced the biosynthesis and signaling pathway of ABA in both female and male B. dactyloides plants, contrasting with the suppression of IAA and JA pathways. Also, we discovered BdMPK8-like as a potential enhancer of drought tolerance in yeast, highlighting novel mechanisms. This study demonstrated the physiological and molecular mechanisms differences between male and female B. dactyloides in response to drought stress, providing a theoretical basis for the corresponding application of female and male B. dactyloides. Additionally, it enriches our understanding of drought resistance mechanisms in dioecious plants, opening avenues for future research and genetic improvement.

Carex breviculmis is an excellent native grass species of the Carex L. of the Cyperaceae family. It has strong resistance and outstanding water-saving advantages, which is widely used in landscaping and understory ecological management. However, the strong seed shattering affects the seed yield and increases the risk of seed harvesting,which not only enhances the difficulty of seed production,but also limits the large-scale application of C. breviculmis. In order to explore the intrinsic mechanism of seed shattering in C. breviculmis, this study analyzed the histology, physiology, and transcriptomics of C. breviculmisseeds. Through histological observation, it was found that there are obvious abscission zones on the seeds, mainly distributed at the end of the seeds. By measuring the physiological indicators, it was found that the cellulase activity in the abscission zone gradually increased with the development of the spike at different stages, and was significantly positively correlated with the degree of seed shattering. In addition, the changes in the content of gibberellin, cytokinin, and ethylene in the abscission zone were significantly correlated with the breaking tensile strength. The second-generation transcriptome sequencing data of the abscission zone indicate that the main pathways involved in seed shattering include "plant hormone signaling transduction", "phenylalanine biosynthesis", and "starch and sucrose metabolism", and many key genes that may be involved in the seed shattering process have been identified. This study provides new insights into the seed shattering mechanism of C. breviculmis and has important theoretical and practical significance for breeding low seed shattering C. breviculmisvarieties.