Anthracnose fruit rot(AFR),caused by the fungal pathogen Colletotrichum fioriniae,is among the most destructive and widespread fruit disease of blueberry,impacting both yield and overall fruit quality.Blueberry cultiv...Anthracnose fruit rot(AFR),caused by the fungal pathogen Colletotrichum fioriniae,is among the most destructive and widespread fruit disease of blueberry,impacting both yield and overall fruit quality.Blueberry cultivars have highly variable resistance against AFR.To date,this pathogen is largely controlled by applying various fungicides;thus,a more cost-effective and environmentally conscious solution for AFR is needed.Here we report three quantitative trait loci associated with AFR resistance in northern highbush blueberry(Vaccinium corymbosum).Candidate genes within these genomic regions are associated with the biosynthesis of flavonoids(e.g.anthocyanins)and resistance against pathogens.Furthermore,we examined gene expression changes in fruits following inoculation with Colletotrichum in a resistant cultivar,which revealed an enrichment of significantly differentially expressed genes associated with certain specialized metabolic pathways(e.g.flavonol biosynthesis)and pathogen resistance.Using non-targeted metabolite profiling,we identified a flavonol glycoside with properties consistent with a quercetin rhamnoside as a compound exhibiting significant abundance differences among the most resistant and susceptible individuals from the genetic mapping population.Further analysis revealed that this compound exhibits significant abundance differences among the most resistant and susceptible individuals when analyzed as two groups.However,individuals within each group displayed considerable overlapping variation in this compound,suggesting that its abundance may only be partially associated with resistance against C.fioriniae.These findings should serve as a powerful resource that will enable breeding programs to more easily develop new cultivars with superior resistance to AFR and as the basis of future research studies.展开更多
Metabolite transport processes and primary metabolism are highly interconnected. This study exam- ined the importance of source-to-sink nitrogen partition- ing, and associated nitrogen metabolism for carbon capture, t...Metabolite transport processes and primary metabolism are highly interconnected. This study exam- ined the importance of source-to-sink nitrogen partition- ing, and associated nitrogen metabolism for carbon capture, transport and usage. Specifically, Arabidopsis aap8 （AMINO ACID PERMEASE 8） mutant lines were analyzed to resolve the consequences of reduced amino acid phloem loading for source leaf carbon metabolism, sucrose phloem transport and sink development during vegetative and reproductive growth phase. Results showed that decreased amino acid transport had a negative effect on sink development of aap8 lines throughout the life cycle, leading to an overall decrease in plant biomass. During vegetative stage, photosynthe- sis and carbohydrate levels were decreased in aap8 leaves, while expression of carbon metabolism and transport genes, as well as sucrose phloem transport were not affected despite reduced sink strength. However, when aap8 plants transitioned to reproductive phase, carbon fixation and assimilation as well as sucrose partitioning to siliques were strongly decreased. Overall, this work demonstrates that phloem loading of nitrogen has varying implications for carbon fixation, assimilation and source-to-sink allocation depending on plant growth stage. It further suggests alterations in source-sink relationships, and regulation of carbon metabolism and transport by sink strength in a development-dependent manner.展开更多
基金This work was supported by United States Department of Agriculture-Agriculture and Food Research Initiative(USDA-AFRI)#2018-67013-27592 to G.S.,T.M.and P.P.E.United States Department of Agriculture-Specialty Crop Research Initiative(USDASCRI)#2019-51181-30015 to P.P.E.+2 种基金National Institute of Health(NIH)Training Grant#T32-GM110523National Science Foundation(NSF)Training Grant DGE-1828149 to M.J.and P.P.EThis work was also supported by Michigan State University AgBioRe search and United States Department of Agriculture-HATCH MICL02742 to P.P.E.
文摘Anthracnose fruit rot(AFR),caused by the fungal pathogen Colletotrichum fioriniae,is among the most destructive and widespread fruit disease of blueberry,impacting both yield and overall fruit quality.Blueberry cultivars have highly variable resistance against AFR.To date,this pathogen is largely controlled by applying various fungicides;thus,a more cost-effective and environmentally conscious solution for AFR is needed.Here we report three quantitative trait loci associated with AFR resistance in northern highbush blueberry(Vaccinium corymbosum).Candidate genes within these genomic regions are associated with the biosynthesis of flavonoids(e.g.anthocyanins)and resistance against pathogens.Furthermore,we examined gene expression changes in fruits following inoculation with Colletotrichum in a resistant cultivar,which revealed an enrichment of significantly differentially expressed genes associated with certain specialized metabolic pathways(e.g.flavonol biosynthesis)and pathogen resistance.Using non-targeted metabolite profiling,we identified a flavonol glycoside with properties consistent with a quercetin rhamnoside as a compound exhibiting significant abundance differences among the most resistant and susceptible individuals from the genetic mapping population.Further analysis revealed that this compound exhibits significant abundance differences among the most resistant and susceptible individuals when analyzed as two groups.However,individuals within each group displayed considerable overlapping variation in this compound,suggesting that its abundance may only be partially associated with resistance against C.fioriniae.These findings should serve as a powerful resource that will enable breeding programs to more easily develop new cultivars with superior resistance to AFR and as the basis of future research studies.
基金supported by the U.S. National Science Foundation grant number IOS 1021286 and IOS 1457183
文摘Metabolite transport processes and primary metabolism are highly interconnected. This study exam- ined the importance of source-to-sink nitrogen partition- ing, and associated nitrogen metabolism for carbon capture, transport and usage. Specifically, Arabidopsis aap8 （AMINO ACID PERMEASE 8） mutant lines were analyzed to resolve the consequences of reduced amino acid phloem loading for source leaf carbon metabolism, sucrose phloem transport and sink development during vegetative and reproductive growth phase. Results showed that decreased amino acid transport had a negative effect on sink development of aap8 lines throughout the life cycle, leading to an overall decrease in plant biomass. During vegetative stage, photosynthe- sis and carbohydrate levels were decreased in aap8 leaves, while expression of carbon metabolism and transport genes, as well as sucrose phloem transport were not affected despite reduced sink strength. However, when aap8 plants transitioned to reproductive phase, carbon fixation and assimilation as well as sucrose partitioning to siliques were strongly decreased. Overall, this work demonstrates that phloem loading of nitrogen has varying implications for carbon fixation, assimilation and source-to-sink allocation depending on plant growth stage. It further suggests alterations in source-sink relationships, and regulation of carbon metabolism and transport by sink strength in a development-dependent manner.
