A bud sport is a lateral shoot,inflorescence or single flower/fruit with a visibly different phenotype from the rest of the plant.The new phenotype is often caused by a stable somatic mutation in a single cell that is...A bud sport is a lateral shoot,inflorescence or single flower/fruit with a visibly different phenotype from the rest of the plant.The new phenotype is often caused by a stable somatic mutation in a single cell that is passed on to its clonal descendants and eventually populates part or all of a meristem.In many cases,a bud sport can be vegetatively propagated,thereby preserving the novel phenotype without sexual reproduction.Bud sports provide new characteristics while retaining the desirable qualities of the parent plant,which is why many bud sports have been developed into popular cultivars.We present an overview of the history of bud sports,the causes and methods of detecting somaclonal variation,and the types of mutant phenotypes that have arisen spontaneously.We focus on examples where the molecular or cytological changes causing the phenotype have been identified.Analysis of these sports has provided valuable insight into developmental processes,gene function and regulation,and in some cases has revealed new information about layer-specific roles of some genes.Examination of the molecular changes causing a phenotype and in some cases reversion back to the original state has contributed to our understanding of the mechanisms that drive genomic evolution.展开更多
Rubus fruits are high-value crops that are sought after by consumers for their flavor,visual appeal,and health benefits.To meet this demand,production of red and black raspberries(R.idaeus L.and R.occidentalis L.),bla...Rubus fruits are high-value crops that are sought after by consumers for their flavor,visual appeal,and health benefits.To meet this demand,production of red and black raspberries(R.idaeus L.and R.occidentalis L.),blackberries(R.subgenus Rubus),and hybrids,such as Boysenberry and marionberry,is growing worldwide.Rubus breeding programmes are continually striving to improve flavor,texture,machine harvestability,and yield,provide pest and disease resistance,improve storage and processing properties,and optimize fruits and plants for different production and harvest systems.Breeders face numerous challenges,such as polyploidy,the lack of genetic diversity in many of the elite cultivars,and until recently,the relative shortage of genetic and genomic resources available for Rubus.This review will highlight the development of continually improving genetic maps,the identification of Quantitative Trait Loci(QTL)s controlling key traits,draft genomes for red and black raspberry,and efforts to improve gene models.The development of genetic maps and markers,the molecular characterization of wild species and germplasm,and highthroughput genotyping platforms will expedite breeding of improved cultivars.Fully sequenced genomes and accurate gene models facilitate identification of genes underlying traits of interest and enable gene editing technologies such as CRISPR/Cas9.展开更多
Black raspberry(Rubus occidentalis L.)is a niche fruit crop valued for its flavor and potential health benefits.The improvement of fruit and cane characteristics via molecular breeding technologies has been hindered b...Black raspberry(Rubus occidentalis L.)is a niche fruit crop valued for its flavor and potential health benefits.The improvement of fruit and cane characteristics via molecular breeding technologies has been hindered by the lack of a high-quality reference genome.The recently released draft genome for black raspberry(ORUS 4115-3)lacks assembly of scaffolds to chromosome scale.We used high-throughput chromatin conformation capture(Hi-C)and Proximity-Guided Assembly(PGA)to cluster and order 9650 out of 11,936 contigs of this draft genome assembly into seven pseudo-chromosomes.The seven pseudo-chromosomes cover~97.2%of the total contig length(~223.8 Mb).Locating existing genetic markers on the physical map resolved multiple discrepancies in marker order on the genetic map.Centromeric regions were inferred from recombination frequencies of genetic markers,alignment of 303 bp centromeric sequence with the PGA,and heat map showing the physical contact matrix over the entire genome.We demonstrate a high degree of synteny between each of the seven chromosomes of black raspberry and a high-quality reference genome for strawberry(Fragaria vesca L.)assembled using only PacBio long-read sequences.We conclude that PGA is a cost-effective and rapid method of generating chromosome-scale assemblies from Illumina short-read sequencing data.展开更多
基金This work was funded by the New Zealand Ministry of Business,Innovation and Employment,contract C11X1310 and internal funding by The New Zealand Institute for Plant and Food Research Limited.
文摘A bud sport is a lateral shoot,inflorescence or single flower/fruit with a visibly different phenotype from the rest of the plant.The new phenotype is often caused by a stable somatic mutation in a single cell that is passed on to its clonal descendants and eventually populates part or all of a meristem.In many cases,a bud sport can be vegetatively propagated,thereby preserving the novel phenotype without sexual reproduction.Bud sports provide new characteristics while retaining the desirable qualities of the parent plant,which is why many bud sports have been developed into popular cultivars.We present an overview of the history of bud sports,the causes and methods of detecting somaclonal variation,and the types of mutant phenotypes that have arisen spontaneously.We focus on examples where the molecular or cytological changes causing the phenotype have been identified.Analysis of these sports has provided valuable insight into developmental processes,gene function and regulation,and in some cases has revealed new information about layer-specific roles of some genes.Examination of the molecular changes causing a phenotype and in some cases reversion back to the original state has contributed to our understanding of the mechanisms that drive genomic evolution.
文摘Rubus fruits are high-value crops that are sought after by consumers for their flavor,visual appeal,and health benefits.To meet this demand,production of red and black raspberries(R.idaeus L.and R.occidentalis L.),blackberries(R.subgenus Rubus),and hybrids,such as Boysenberry and marionberry,is growing worldwide.Rubus breeding programmes are continually striving to improve flavor,texture,machine harvestability,and yield,provide pest and disease resistance,improve storage and processing properties,and optimize fruits and plants for different production and harvest systems.Breeders face numerous challenges,such as polyploidy,the lack of genetic diversity in many of the elite cultivars,and until recently,the relative shortage of genetic and genomic resources available for Rubus.This review will highlight the development of continually improving genetic maps,the identification of Quantitative Trait Loci(QTL)s controlling key traits,draft genomes for red and black raspberry,and efforts to improve gene models.The development of genetic maps and markers,the molecular characterization of wild species and germplasm,and highthroughput genotyping platforms will expedite breeding of improved cultivars.Fully sequenced genomes and accurate gene models facilitate identification of genes underlying traits of interest and enable gene editing technologies such as CRISPR/Cas9.
文摘Black raspberry(Rubus occidentalis L.)is a niche fruit crop valued for its flavor and potential health benefits.The improvement of fruit and cane characteristics via molecular breeding technologies has been hindered by the lack of a high-quality reference genome.The recently released draft genome for black raspberry(ORUS 4115-3)lacks assembly of scaffolds to chromosome scale.We used high-throughput chromatin conformation capture(Hi-C)and Proximity-Guided Assembly(PGA)to cluster and order 9650 out of 11,936 contigs of this draft genome assembly into seven pseudo-chromosomes.The seven pseudo-chromosomes cover~97.2%of the total contig length(~223.8 Mb).Locating existing genetic markers on the physical map resolved multiple discrepancies in marker order on the genetic map.Centromeric regions were inferred from recombination frequencies of genetic markers,alignment of 303 bp centromeric sequence with the PGA,and heat map showing the physical contact matrix over the entire genome.We demonstrate a high degree of synteny between each of the seven chromosomes of black raspberry and a high-quality reference genome for strawberry(Fragaria vesca L.)assembled using only PacBio long-read sequences.We conclude that PGA is a cost-effective and rapid method of generating chromosome-scale assemblies from Illumina short-read sequencing data.
