Tea is an important cash crop, representing a $40 billion-a-year global market. Differentiation of the tea market has resulted in increasing demand for tea products that are sustainably and responsibly produced. Tea a...Tea is an important cash crop, representing a $40 billion-a-year global market. Differentiation of the tea market has resulted in increasing demand for tea products that are sustainably and responsibly produced. Tea authentication is important because of growing concerns about fraud involving premium tea products. Analytical technologies are needed for protection and value enhancement of high-quality brands. For loose-leaf teas, the challenge is that the authentication needs to be established on the basis of a single leaf, so that the products can be traced back to the original varieties. A new generation of molecular markers offers an ideal solution for authentication of processed agricultural products. Using a nanofluidic array to identify variant SNP sequences, we tested genetic identities using DNA extracted from single leaves of 14 processed commercial tea products. Based on the profiles of 60 SNP markers, the genetic identity of each tea sample was unambiguously identified by multilocus matching and ordination analysis. Results for repeated samples of multiple tea leaves from the same products(using three independent DNA extractions) showed 100% concordance, showing that the nanofluidic system is a reliable platform for generating tea DNA fingerprints with high accuracy. The method worked well on green, oolong, and black teas, and can handle a large number of samples in a short period of time. It is robust and cost-effective, thus showing high potential for practical application in the value chain of the tea industry.展开更多
Dragon fruits are tropical fruits economically important for agricultural industries.As members of the family of Cactaceae,they have evolved to adapt to the arid environment.Here we report the draft genome of Hylocere...Dragon fruits are tropical fruits economically important for agricultural industries.As members of the family of Cactaceae,they have evolved to adapt to the arid environment.Here we report the draft genome of Hylocereus undatus,commercially known as the white-fleshed dragon fruit.The chromosomal level genome assembly contains 11 longest scaffolds corresponding to the 11 chromosomes of H.undatus.Genome annotation of H.undatus found~29,000 protein-coding genes,similar to Carnegiea gigantea(saguaro).Whole-genome duplication(WGD)analysis revealed a WGD event in the last common ancestor of Cactaceae followed by extensive genome rearrangements.The divergence time between H.undatus and C.gigantea was estimated to be 9.18 MYA.Functional enrichment analysis of orthologous gene clusters(OGCs)in six Cactaceae plants found significantly enriched OGCs in drought resistance.Fruit flavor-related functions were overrepresented in OGCs that are significantly expanded in H.undatus.The H.undatus draft genome also enabled the discovery of carbohydrate and plant cell wall-related functional enrichment in dragon fruits treated with trypsin for a longer storage time.Lastly,genes of the betacyanin(a red-violet pigment and antioxidant with a very high concentration in dragon fruits)biosynthetic pathway were found to be co-localized on a 12 Mb region of one chromosome.The consequence may be a higher efficiency of betacyanin biosynthesis,which will need experimental validation in the future.The H.undatus draft genome will be a great resource to study various cactus plants.展开更多
Cacao(Theobroma cacao L.)is an important Neotropical crop originating in South America and dispersed by European explorers,arriving in Madagascar in the late 19th century.Although Madagascar is an important producer o...Cacao(Theobroma cacao L.)is an important Neotropical crop originating in South America and dispersed by European explorers,arriving in Madagascar in the late 19th century.Although Madagascar is an important producer of cocoa for the premium chocolate market,the varietal composition and genetic diversity in cacao germplasm from Madagascar,especially in traditional cacao farms,remains unknown.A total of 190 cacao accessions,including 40 farmer accessions collected from traditional cacao farms in Madagascar,and 150 accessions representing seven reference cacao populations,were analyzed using Single Nucleotide Polymorphism(SNP)markers.Multivariate analysis and Bayesian stratification resulted in the clustering of the 40 farmer accessions into three groups:Criollo,Amelonado and Trinitario.These three traditional varieties were commonly cultivated in tropical America in the 18th century,but most of them have been replaced by improved varieties.The present study demonstrated that Madagascar is distinctive in that all three traditional cacao varieties,Criollo,Amelonado and Trinitario,are still maintained on-farm for cocoa production,as in Mesoamerica and the Caribbean several hundred years ago.Results from the present study are significant in terms of understanding the early dispersal of cacao from tropical America and Asia to Africa,in addition to the well-documented route from Brazil to São Tomé&Príncipe.The results also provide new information for planning future conservation and utilization of cacao germplasm in Madagascar.展开更多
文摘Tea is an important cash crop, representing a $40 billion-a-year global market. Differentiation of the tea market has resulted in increasing demand for tea products that are sustainably and responsibly produced. Tea authentication is important because of growing concerns about fraud involving premium tea products. Analytical technologies are needed for protection and value enhancement of high-quality brands. For loose-leaf teas, the challenge is that the authentication needs to be established on the basis of a single leaf, so that the products can be traced back to the original varieties. A new generation of molecular markers offers an ideal solution for authentication of processed agricultural products. Using a nanofluidic array to identify variant SNP sequences, we tested genetic identities using DNA extracted from single leaves of 14 processed commercial tea products. Based on the profiles of 60 SNP markers, the genetic identity of each tea sample was unambiguously identified by multilocus matching and ordination analysis. Results for repeated samples of multiple tea leaves from the same products(using three independent DNA extractions) showed 100% concordance, showing that the nanofluidic system is a reliable platform for generating tea DNA fingerprints with high accuracy. The method worked well on green, oolong, and black teas, and can handle a large number of samples in a short period of time. It is robust and cost-effective, thus showing high potential for practical application in the value chain of the tea industry.
文摘Dragon fruits are tropical fruits economically important for agricultural industries.As members of the family of Cactaceae,they have evolved to adapt to the arid environment.Here we report the draft genome of Hylocereus undatus,commercially known as the white-fleshed dragon fruit.The chromosomal level genome assembly contains 11 longest scaffolds corresponding to the 11 chromosomes of H.undatus.Genome annotation of H.undatus found~29,000 protein-coding genes,similar to Carnegiea gigantea(saguaro).Whole-genome duplication(WGD)analysis revealed a WGD event in the last common ancestor of Cactaceae followed by extensive genome rearrangements.The divergence time between H.undatus and C.gigantea was estimated to be 9.18 MYA.Functional enrichment analysis of orthologous gene clusters(OGCs)in six Cactaceae plants found significantly enriched OGCs in drought resistance.Fruit flavor-related functions were overrepresented in OGCs that are significantly expanded in H.undatus.The H.undatus draft genome also enabled the discovery of carbohydrate and plant cell wall-related functional enrichment in dragon fruits treated with trypsin for a longer storage time.Lastly,genes of the betacyanin(a red-violet pigment and antioxidant with a very high concentration in dragon fruits)biosynthetic pathway were found to be co-localized on a 12 Mb region of one chromosome.The consequence may be a higher efficiency of betacyanin biosynthesis,which will need experimental validation in the future.The H.undatus draft genome will be a great resource to study various cactus plants.
文摘Cacao(Theobroma cacao L.)is an important Neotropical crop originating in South America and dispersed by European explorers,arriving in Madagascar in the late 19th century.Although Madagascar is an important producer of cocoa for the premium chocolate market,the varietal composition and genetic diversity in cacao germplasm from Madagascar,especially in traditional cacao farms,remains unknown.A total of 190 cacao accessions,including 40 farmer accessions collected from traditional cacao farms in Madagascar,and 150 accessions representing seven reference cacao populations,were analyzed using Single Nucleotide Polymorphism(SNP)markers.Multivariate analysis and Bayesian stratification resulted in the clustering of the 40 farmer accessions into three groups:Criollo,Amelonado and Trinitario.These three traditional varieties were commonly cultivated in tropical America in the 18th century,but most of them have been replaced by improved varieties.The present study demonstrated that Madagascar is distinctive in that all three traditional cacao varieties,Criollo,Amelonado and Trinitario,are still maintained on-farm for cocoa production,as in Mesoamerica and the Caribbean several hundred years ago.Results from the present study are significant in terms of understanding the early dispersal of cacao from tropical America and Asia to Africa,in addition to the well-documented route from Brazil to São Tomé&Príncipe.The results also provide new information for planning future conservation and utilization of cacao germplasm in Madagascar.
