Rosaceae represents a vast and complex group of species,with its classification being intricate and contentious.The taxonomic placement of many species within this family has been a subject of ongoing debate.The study utilized the Illumina platform to sequence 19 plant species from 10 genera in the Rosaceae.The cp genomes,vary-ing in size from 153,366 to 159,895 bp,followed the typical quadripartite organization consisting of a large single-copy(LSC)region(84,545 to 87,883 bp),a small single-copy(SSC)region(18,174 to 19,259 bp),and a pair of inverted repeat(IR)regions(25,310 to 26,396 bp).These genomes contained 132–138 annotated genes,including 87 to 93 protein-coding genes(PCGs),37 tRNA genes,and 8 rRNA genes using MISA software,52 to 121 simple sequence repeat(SSR)loci were identified.D.arbuscular contained the least of SSRs and did not have hexanotides,A.lineata contained the richest SSRs.Long terminal repeats(LTRs)were primarily composed of palindromic and forward repeat sequences,meanwhile,The richest LTRs were found in Argentina lineata.Except for Argentina lineata,Fragariastrum eriocarpum,and Prunus trichostoma,which varied in gene type and position on both sides of the boundary,the remaining species were found to be mostly conserved according to IR boundary analysis.The examination of the Ka/Ks ratio revealed that only the infA gene had a value greater than 1,indicating that this gene was primarily subjected to positive selection during evolution.Additionally,9 hotspots of variation were identified in the LSC and SSC regions.Phylogenetic analysis confirmed the scientific validity of the genus Prunus L.sensu lato(s.l.)within the Rosaceae family.The separation of the three genera Argentina Hill,Fragariastrum Heist.ex Fabr.and Dasiphora Raf.from Potentilla L.may be a more scientific classification.These results offer fresh perspectives on the taxonomy of the Rosaceae.
The stem barks of Prunus africana are used in the treatment of the benign prostate. Cameroon is one of the important exporters of the barks. Despite the important measures adopted in Cameroon for sustaining its harvesting, some many chalenges still remain. The objective of this work is to refine the forest management parameters in relation to P. africana in the regions of Adamaoua and the South-West by developing a volume rate which makes it possible to estimate the production for a new stem. The work took place in two phases: in the South-West in 2010 and in Adamaoua in 2011. Data collection used the semi-direct method, while the cubing equation was deduced by the multiple linear regression method. Two models for volume estimation and three models for mass prediction were developed. The predictive parameters retained are diameter, height of the bole and thickness of the bark. Results show that the average mass of the dry bark for a given P. africana tree species is 27.55 ± 14.44 kg and this varies according to the site. The strong adjusted coefficient of determination (adjusted R2) observed illustrates the reliability of the proposed models. These models provide a reliable tool that can be adopted as a standard in Cameroon for P. africana.
In overlapping distribution areas of Sorbus pohuashanensis and S.discolor in North China(Mount Tuoliang,Mount Xiling and Mount Baihua),Sorbus indi-viduals were found with pink fruit,which have never been recorded for the flora of China.Fourteen morphological characters combined with four chloroplast DNA markers and internal transcribed spacer(ITS)were used to analyze the origin of the Sorbus individuals with pink fruits and their relationship to S.pohuashanensis and S.discolor.PCA,SDA and one-way(taxon)ANOVA of morphological characters provided convincing evidence of the hybrid ori-gin of Sorbus individuals with pink fruits based on a novel morphological character and many intermediate characters.Haplotype analysis based on four cpDNA markers showed that either S.pohuashanensis or S.discolor were maternal parents of Sorbus individuals with pink fruits.Incongru-ence of the position of Sorbus individuals with pink fruits between cpDNA and ITS in cluster trees supported by DNA sequence comparative analysis,implying former hybridiza-tion events between S.pohuashanensis and S.discolor.Mul-tiple hybridization events between S.pohuashanensis and S.discolor might have contributed to the generation of Sorbus individuals with pink fruits.This study has provided insights into hybridization between species of the same genus in sympatric areas,which is of great significance for the study of interspecific hybridization.
