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Cryptomeria fortunei is the indigenous evergreen coniferous timber species in southern China, valued for its superior wood quality, which frequently finds industrial applications. MiRNAs (microRNAs) can be involved in regulating various aspects of plant growth, and more and more studies have explored miRNAs related to growth and development, but among them, the ones on C. fortunei are relatively rare. In this study, we screened miRNAs that were differentially expressed during vascular cambium development, and chose miR159a and CfMYB37 as candidate genes for cloning and functional validation. The results showed that miR159a had CfMYB37 as a target gene and that there was a distinct negative regulatory relationship between miR159a and CfMYB37 in C. fortunei. 35 S::miR159a plants were taller than WT and had thicker stems than WT, and miR159a encouraged the growth of xylem cells and lignin. While 35 S::mCfMYB37 plants had the opposite phenotype to 35 S::miR159a plants, with considerably lower lignin content and xylem cell layer number compared to WT, 35 S::CfMYB37 plants lacked a distinctive phenotype. This suggests that the miR159- CfMYB37 module can control plant growth and xylem development. For the following investigation of C. fortunei 's growth and vascular cambium development as well as the enhancement of its wood qualities, this work serves as a crucial theoretical foundation. • Screening from transcriptome and miRNA sequencing data for differentially expressed miR159 and CfMYB37 in C. fortunei. • MiR159a and its target gene CfMYB37 were cloned from C. fortunei. • MiR159 negatively regulates the expression of CfMYB37 in different growth stages of C. fortunei. • CfMYB37 was nucleus localization proteins. • The miR159a-CfMYB37 module plays an important role in the development of xylem and regulates the synthesis of lignin. [ABSTRACT FROM AUTHOR]

R2R3-MYB, the largest subfamily in MYB transcription factor (TF), plays a crucial role in regulating numerous aspects of growth and development of plants. Whereas, a comprehensive identification and characterization of R2R3-MYBs have not been elucidated in Cryptomeria fortunei Hooibrenk. C. fortunei is the indigenous evergreen coniferous timber species in southern China. Here, we aimed to understand the functional roles of CfMYBs during lignin biosynthesis. Therefore, we conducted systematic transcriptome-wide mining to explore biological functions and expression profiles of CfMYBs. A total of 35 CfMYBs were screened from transcriptome data, which could further be subdivided into 16 groups through phylogenetic analysis. Besides, they all shared a highly conserved R2R3 domain that could form helix-turn-helix (HTH) structure. The expression patterns revealed that CfMYBs participated in various biological processes. Moreover, the interaction network suggested that CfMYBs regulated many metabolic pathways as upstream regulatory switches. Further verification uncovered that CfMYB25 and CfMYB13 were nucleus localization proteins. CfMYB25 , a transcriptional repressor, negatively regulated the lignin deposition and secondary cell wall (SCW) formation. These results provide new insights into the functional verification of CfMYBs and lay a foundation for understanding their regulatory roles in lignin biosynthesis. • A total of 35 R2R3-CfMYB TFs were identified from the transcriptome data of C. fortunei vascular cambium. • These R2R3-CfMYB TFs were clustered into diverse evolutionary branches, including the "Regulation of secondary cell wall". • Most R2R3-CfMYBs were highly expressed in stages B and D. • CfMYB25 and CfMYB13 were nucleus localization proteins. • CfMYB25 , a transcriptional repressor, negatively regulated the lignin biosynthesis and secondary cell wall formation. [ABSTRACT FROM AUTHOR]

The relationships between soil respiration and environmental factors determine the effect of warming soil on the carbon balance in temperate forest ecosystems and on changes in atmospheric CO2 concentrations. Here, we used 3 years of data regarding soil respiration rates ( Rs), soil temperature ( Ts), and soil volumetric water content ( θ) from a 50-year-old mature cedar ( Platycladus orientalis L.) plantation at Jiufeng Mountain, Beijing, China, to demonstrate the seasonal and interannual variation of Rs dependence on Ts and θ throughout the period 2008-2010. We used the exponential model to calculate the temperature sensitivity indicator Q10 and we examined the annual and seasonal patterns of Rs and Q10. The Rs correlated with Ts annually ( p < 0.05). The Rs- Ts exponential relationship was significant in the autumn and winter ( p < 0.05), while the combined Ts and θ relationships with Rs were significant in the spring and summer ( p < 0.001). The spring Rs anomalies caused by drought appeared to have carryover effects that translated to Rs anomalies in the following summer. Finally, the summer Rs, which was influenced by the coincident precipitation and θ anomalies, determined the magnitude of the annual total amount of soil respiration. This result has implications for how abiotic factors may drive shifts in seasonal patterns of soil respiration under a changing climate. [ABSTRACT FROM AUTHOR]