Search

Rhododendron simsii Planchon is an important ornamental species in the northern hemisphere. Flower color is an important objective of Rhododendron breeding programs. However, information on anthocyanin synthesis in R. simsii is limited. In this research, the regulatory mechanism of anthocyanin biosynthesis in R. simsii was performed through the integrated analysis of metabolome and RNA-seq. A total of 805 and 513 metabolites were screened by positive and negative ionization modes, respectively, In total, 79 flavonoids contained seven anthocyanidins, 42 flavanones, 10 flavans, 13 flavones, and seven flavonols. Methylated and glycosylated derivatives took up the most. Differentially accumulated metabolites were mainly involved in "flavone and flavonol biosynthesis", "cyanoamino acid metabolism", "pyrimidine metabolism", and "phenylalanine metabolism" pathways. For flavonoid biosynthesis, different expression of shikimate O-hydroxycinnamoyltransferase, caffeoyl-CoA O-methyltransferase, flavonoid 3′-monooxygenase, flavonol synthase, dihydroflavonol 4-reductase/flavanone 4-reductase, F3′5′H, chalcone synthase, leucoanthocyanidin reductase, and 5-O-(4-coumaroyl)-D-quinate 3′-monooxygenase genes ultimately led to different accumulations of quercetin, myricetin, cyanidin, and eriodictyol. In flavone and flavonol biosynthesis pathway, differential expression of F3′5′H, flavonoid 3′-monooxygenase and flavonol-3-O-glucoside/galactoside glucosyltransferase genes led to the differential accumulation of quercetin, isovitexin, and laricitrin. This research will provide a biochemical basis for further modification of flower color and genetic breeding in R. simsii and related Rhododendron species. [ABSTRACT FROM AUTHOR]

Abstract: The key process in speciation concerns the formation and maintenance of reproductive isolating barriers between diverging lineages. Although species boundaries are frequently investigated between two species across many taxa, reproductive isolating barriers among multiple species (>2) that would represent the most common phenomenon in nature, remain to be clarified. Here, we use double digest restriction‐site associated DNA (ddRAD) sequencing to examine patterns of hybridization at a sympatric site where three Ligularia species grow together and verify whether those patterns contribute to the maintenance of boundaries among species. The results based on the RAD SNP datasets indicated hybridization Ligularia cyathiceps × L. duciformis and L. duciformis × L. yunnanensis were both restricted to F1s plus a few first‐generation backcrosses and no gene introgression were identified, giving rise to strong reproductive isolation among hybridizing species. Moreover, hybrid swarm simulation, using HYBRIDLAB, indicated the RAD SNP datasets had sufficient discriminatory power for accurate hybrid detection. We conclude that parental species show strong reproductive isolation and they still maintain species boundaries, which may be the key mechanism to maintain species diversity of Ligularia in the eastern Qinghai‐Tibetan Plateau and adjacent areas. Moreover, this study highlights the effectiveness of RAD sequencing in hybridization studies. [ABSTRACT FROM AUTHOR]

Colasposoma dauricum Mannerheim, 1849, is an important insect pest distributed in most areas of China. The complete mitochondrial genome of C. dauricum was sequenced and analyzed. The phylogenetic relationships between C. dauricum and other 10 species in the superfamily Chrysomeloidea were reconstructed using maximum likelihood (ML) methods based on the concatenated nucleotide sequences, the phylogenetic analysis showed that C. dauricum is closely related to Basilepta fulvipes in the same subfamily. [ABSTRACT FROM AUTHOR]

The Amyloporia genus is an important Chinese medicinal fungus. Here, we present a draft genome sequence of Amyloporia xantha strain YAFMF0618. The genome resource will support subsequent research into the potential secondary metabolite diversity of A. xantha .

Here, we report a draft genome sequence of endophytic fungus Nemania diffusa YAFEF818, isolated from Artemisia argyi . Oxford Nanopore Technologies PromethION and Illumina NovaSeq sequence reads were assembled using NECAT and polished using pilon to yield a 55.63 Mb genome., Competing Interests: The authors declare no conflict of interest.

Rhododendronmariesii Hemsley et Wilson, 1907, a typical member of the family Ericaeae, possesses valuable medicinal and horticultural properties. In this research, the complete chloroplast (cp) genome of R.mariesii was sequenced and assembled, which proved to be a typical quadripartite structure with the length of 203,480 bp. In particular, the lengths of the large single copy region (LSC), small single copy region (SSC), and inverted repeat regions (IR) were 113,715 bp, 7,953 bp, and 40,918 bp, respectively. Among the 151 unique genes, 98 were protein-coding genes, 8 were tRNA genes, and 45 were rRNA genes. The structural characteristics of the R.mariesii cp genome was similar to other angiosperms. Leucine was the most representative amino acid, while cysteine was the lowest representative. Totally, 30 codons showed obvious codon usage bias, and most were A/U-ending codons. Six highly variable regions were observed, such as trnK-pafI and atpE-rpoB , which could serve as potential markers for future barcoding and phylogenetic research of R.mariesii species. Coding regions were more conserved than non-coding regions. Expansion and contraction in the IR region might be the main length variation in R.mariesii and related Ericaeae species. Maximum-likelihood (ML) phylogenetic analysis revealed that R.mariesii was relatively closed to the R.simsii Planchon, 1853 and R.pulchrum Sweet,1831. This research will supply rich genetic resource for R.mariesii and related species of the Ericaeae., Competing Interests: The authors declare that they have no competing interests., (Zhiliang Li, Zhiwei Huang, Xuchun Wan, Jiaojun Yu, Hongjin Dong, Jialiang Zhang, Chunyu Zhang, Shuzhen Wang.)