RESUMO
The completed chloroplast genome of Gastrodia elata Blume (G. elata) from Korea was determined in this study. The cpDNA is 35,230 bp in length and lacked the large and small single copy (LSC and SSC) regions, due to the lost inverted repeat (IR). The overall AT content is 73.30%, and the cpDNA contains 20 protein-coding genes, 5 tRNA genes, and 3 rRNA genes. Remarkably, the Korean G. elata cp genome was 74 bp smaller than that of the Chinese G. elata. It revealed substantial sequence variants 495 SNPs and 75 InDels between the two G. elata genomes.
RESUMO
Nut weight is one of the most important traits that can affect a chestnut grower's returns. Due to the long juvenile phase of chestnut trees, the selection of desired characteristics at early developmental stages represents a major challenge for chestnut breeding. In this study, we identified single nucleotide polymorphisms (SNPs) in transcriptomic regions, which were significantly associated with nut weight in chestnuts (Castanea crenata), using a genome-wide association study (GWAS). RNA-sequencing (RNA-seq) data were generated from large and small nut-bearing trees, using an Illumina HiSeq. 2000 system, and 3,271,142 SNPs were identified. A total of 21 putative SNPs were significantly associated with chestnut weight (false discovery rate [FDR] < 10-5), based on further analyses. We also applied five machine learning (ML) algorithms, support vector machine (SVM), C5.0, k-nearest neighbour (k-NN), partial least squares (PLS), and random forest (RF), using the 21 SNPs to predict the nut weights of a second population. The average accuracy of the ML algorithms for the prediction of chestnut weights was greater than 68%. Taken together, we suggest that these SNPs have the potential to be used during marker-assisted selection to facilitate the breeding of large chestnut-bearing varieties.
Assuntos
Fagaceae/genética , Estudo de Associação Genômica Ampla/métodos , Nozes/genética , Polimorfismo de Nucleotídeo Único , Transcriptoma/genética , Fagaceae/classificação , Genótipo , Aprendizado de Máquina , Fenótipo , Melhoramento Vegetal , Análise de Sequência de RNA/métodos , Especificidade da Espécie , Máquina de Vetores de SuporteRESUMO
The complete chloroplast genome sequence of Castanea crenata was sequenced and assembled using PacBio Sequel data. The cpDNA was 160,787 bp in length, containing a pair of inverted repeats (IRs) of 25,654 bp each separated by a large and small single copy (LSC and SSC) regions of 90,645 bp and 18,836 bp, respectively. The cpDNA contained 102 genes, including 65 protein-coding genes, 8 ribosomal RNA genes and 37 transfer RNA genes. Phylogenetic analysis indicated that C. crenata was closest to C. pumila var. pumila, which is known as a typical variety of American chinquapin or dwarf chestnut.