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Toona fargesii (T. fargesii) is a deciduous tree of the Meliaceae family which is utilized for high-value timber. Interestingly, root sprouting is a typical reproductive pattern in T. fargesii. Nevertheless, the genetics underlying this phenomenon are still unclear. Here, three type of roots of T. fargesii were used for histological observation, plant endogenous hormone determination, non-structural carbohydrate (NSC) determination, and sequencing using the Illumina next-generation and PacBio SMRT platforms. Our results indicated that root sprouts originated from cork cambiums. Furthermore, indole-3-acetic acid (IAA), zeatin riboside (ZR), gibberellic acid 3 (GA3), and abscisic acid (ABA) content was significantly increased, while soluble sugar content was significantly decreased in the root sprouts. In addition, transcriptomic analysis suggested a total of 36.19 G of raw data from which 210 differentially expressed genes (DEGs) of were identified in RS vs. SR. Of these, the candidate DEGs were largely enriched in the citrate cycle, gluconeogenesis, starch and sucrose metabolism, and plant hormone signal transduction pathways. We therefore speculated that the accumulation of cytokinin and auxin might be induced by ATP-binding cassette-B 19 (ABCB19) and ABCG14, which were necessary for root sprouting. Additionally, transcription factors SQUAMOSA promoter binding protein-like 18 (SPL18) and NAM, ATAF1/2, and CUC2-14 (NAC14) were found in response to environmental water and epigenetic modification in RS. Overall, this study was to unravel the physiological and transcriptomic levels of the development of root sprouting in T. fargesii. Full article

The quantitative anatomical characteristics of Quercus variabilis virgin cork grown in Korea were observed by scanning electron microscopy and compared with Quercus suber reproduction cork from Portugal to obtain basic data for further utilization of domestic cork resources in Korean cork industries. Q. variabilis virgin cork showed a smaller growth ring width and higher latecork percentage than Q. suber reproduction cork. Q. variabilis showed a smaller proportion of cork cells and a higher proportion of lenticular channels than Q. suber, whereas sclereid and dark-brown zones were found only in Q. variabilis. The frequency of pentagonal cork cells in the transverse and radial sections was higher in the cork of Q. suber than in Q. variabilis. In the tangential section, Q. variabilis displayed a lower frequency of heptagonal cells and a higher frequency of pentagonal cells than Q. suber.Q. variabilis cork had a smaller cell width, lumen diameter, cell wall thickness, prism base edge and area, total cell volume, and solid volume of the cell wall than Q. suber cork. The fractional solid volume and number of cells per cm³ were higher in Q. variabilis than Q. suber. Full article