Carotenoids are a diverse group of pigments widely distributed in nature.The vivid yellow,orange,and red colors of many horticultural crops are attributed to the overaccumulation of carotenoids,which contribute to a c...Carotenoids are a diverse group of pigments widely distributed in nature.The vivid yellow,orange,and red colors of many horticultural crops are attributed to the overaccumulation of carotenoids,which contribute to a critical agronomic trait for flowers and an important quality trait for fruits and vegetables.Not only do carotenoids give horticultural crops their visual appeal,they also enhance nutritional value and health benefits for humans.As a result,carotenoid research in horticultural crops has grown exponentially over the last decade.These investigations have advanced our fundamental understanding of carotenoid metabolism and regulation in plants.In this review,we provide an overview of carotenoid biosynthesis,degradation,and accumulation in horticultural crops and highlight recent achievements in our understanding of carotenoid metabolic regulation in vegetables,fruits,and flowers.展开更多
Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplas...Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. These plastids have dramatic differences in their capacity to synthesize and sequester carotenoids. Clearly, plastids play a central role in governing carotenogenic activity, carotenoid stability, and pigment diversity. Understanding of carotenoid metabolism and accumulation in various plastids expands our view on the multifaceted regulation of carotenogenesis and facilitates our efforts toward developing nutrient-enriched food crops. In this review, we provide a comprehensive overview of the impact of various types of plastids on carotenoid biosynthesis and accumulation, and discuss recent advances in our understanding of the regulatory control of carotenogenesis and metabolic engineering of carotenoids in light of plastid types in plants.展开更多
Carotenoids are a group of widely distributed natural pigments.They give many horticultural plants the bright red,orange,and yellow colors,as well as the aroma and flavor.Carotenoids enhance the health value and repre...Carotenoids are a group of widely distributed natural pigments.They give many horticultural plants the bright red,orange,and yellow colors,as well as the aroma and flavor.Carotenoids enhance the health value and represent an essential quality trait of horticultural products.Significant efforts have been made to correlate specific carotenoid production with pathway gene expression.Some transcription factors that directly regulate transcription of the pathway genes have been identified.Horticultural crops have evolved with complicated and multifaceted regulatory mechanisms to generate the enormous diversity in carotenoid content and composition.However,the diverse and complex control of carotenoid accumulation is still not well understood.In this review,we depict carotenoid accumulation pathways and highlight the recent progress in the regulatory control of carotenoid accumulation in horticultural plants.Because of the critical roles of chromoplasts for carotenoid hyperproduction,we evaluate chromoplast ultrastructures and carotenoid sequestrations.A perspective on carotenoid research in horticultural crops is provided.展开更多
Phytoene synthase （PSY） is the crucial plastidial enzyme in the carotenoid biosynthetic pathway. However, its post-translational regulation remains elusive. Likewise, Clp protease constitutes a central part of the p...Phytoene synthase （PSY） is the crucial plastidial enzyme in the carotenoid biosynthetic pathway. However, its post-translational regulation remains elusive. Likewise, Clp protease constitutes a central part of the plastid protease network, but its substrates for degradation are not well known. In this study, we report that PSY is a substrate of the Clp protease. PSY was uncovered to physically interact with various Clp protease subunits （i.e., ClpS1, CIpC1, and CIpD）. High levels of PSY and several other carotenogenic enzyme proteins overac- cumulate in the clpcl, clpp4, and clprl-2 mutants. The overaccumulated PSY was found to be partially enzy- matically active. Impairment of Clp activity in clpcl results in a reduced rate of PSY protein turnover, further supporting the role of Clp protease in degrading PSY protein. On the other hand, the ORANGE （OR） protein, a major post-translational regulator of PSY with holdase chaperone activity, enhances PSY protein stability and increases the enzymatically active proportion of PSY in clpcl, counterbalancing CIp-mediated proteol- ysis in maintaining PSY protein homeostasis. Collectively, these findings provide novel insights into the qual- ity control of plastid-localized proteins and establish a hitherto unidentified post-translational regulatory mechanism of carotenogenic enzymes in modulating carotenoid biosynthesis in plants.展开更多
Artemisia argyi Le´vl.et Vant.,a perennial Artemisia herb with an intense fragrance,is widely used in traditional medicine in China and many other Asian countries.Here,we present a chromosome-scale genome assembl...Artemisia argyi Le´vl.et Vant.,a perennial Artemisia herb with an intense fragrance,is widely used in traditional medicine in China and many other Asian countries.Here,we present a chromosome-scale genome assembly of A.argyi comprising 3.89 Gb assembled into 17 pseudochromosomes.Phylogenetic and comparative genomic analyses revealed that A.argyi underwent a recent lineage-specificwhole-genomeduplication(WGD)event after divergence fromArtemisia annua,resulting in two subgenomes.Wedeciphered the diploid ancestral genome of A.argyi,and unbiased subgenome evolution was observed.The recent WGD led to a large number of duplicated genes in the A.argyi genome.Expansion of the terpene synthase(TPS)gene family through various types of gene duplication may have greatly contributed to the diversity of volatile terpenoids in A.argyi.In particular,we identified a typical germacrene D synthase gene cluster within the expanded TPS gene family.The entire biosynthetic pathways of germacrenes,(+)-borneol,and(+)-camphor were elucidated in A.argyi.In addition,partial deletion of the amorpha-4,11-diene synthase(ADS)gene and loss of function of ADS homologs may have resulted in the lack of artemisinin production in A.argyi.Our study provides newinsights into the genome evolution of Artemisia and lays a foundation for further improvement of the quality of this important medicinal plant.展开更多
Carotenoids are isoprenoid metabolites synthesized de novo in all photosynthetic organisms.Carotenoids are essential for plants with diverse functions in photosynthesis,photoprotection,pigmentation,phytohormone synthe...Carotenoids are isoprenoid metabolites synthesized de novo in all photosynthetic organisms.Carotenoids are essential for plants with diverse functions in photosynthesis,photoprotection,pigmentation,phytohormone synthesis,and signaling.They are also critically important for humans as precursors of vitamin A synthesis and as dietary antioxidants.The vital roles of carotenoids to plants and humans have prompted significant progress toward our understanding of carotenoid metabolism and regulation.New regulators and novel roles of carotenoid metabolites are continuously revealed.This review focuses on current status of carotenoid metabolism and highlights recent advances in comprehension of the intrinsic and multi-dimensional regulation of carotenoid accumulation.We also discuss the functional evolution of carotenoids,the agricultural and horticultural application,and some key areas for future research.展开更多
The flesh color of pummelo(Citrus maxima)fruits is highly diverse and largely depends on the level of carotenoids,which are beneficial to human health.It is vital to investigate the regulatory network of carotenoid bi...The flesh color of pummelo(Citrus maxima)fruits is highly diverse and largely depends on the level of carotenoids,which are beneficial to human health.It is vital to investigate the regulatory network of carotenoid biosynthesis to improve the carotenoid content in pummelo.However,the molecular mechanism underlying carotenoid accumulation in pummelo is not fully understood.In this study,we identified a novel histone methyltransferase gene,CgSDG40,involved in carotenoid regulation by analyzing the flesh transcriptome of typical white-fleshed pummelo,red-fleshed pummelo and extreme-colored F1 hybrids from a segregated pummelo population.Expression of CgSDG40 corresponded to flesh color change and was highly coexpressed with CgPSY1.Interestingly,CgSDG40 and CgPSY1 are located physically adjacent to each other on the chromosome in opposite directions,sharing a partially overlapping promoter region.Subcellular localization analysis indicated that CgSDG40 localizes to the nucleus.Overexpression of CgSDG40 significantly increased the total carotenoid content in citrus calli relative to that in wild type.In addition,expression of CgPSY1 was significantly activated in overexpression lines relative to wild type.Taken together,our findings reveal a novel histone methyltransferase regulator,CgSDG40,involved in the regulation of carotenoid biosynthesis in citrus and provide new strategies for molecular design breeding and genetic improvement of fruit color and nutritional quality.展开更多
Marker-assisted selection(MAS)is often employed in crop breeding programs to accelerate and enhance cultivar development,via selection during the juvenile phase and parental selection prior to crossing.Next-generation...Marker-assisted selection(MAS)is often employed in crop breeding programs to accelerate and enhance cultivar development,via selection during the juvenile phase and parental selection prior to crossing.Next-generation sequencing and its derivative technologies have been used for genome-wide molecular marker discovery.To bridge the gap between marker development and MAS implementation,this study developed a novel practical strategy with a semi-automated pipeline that incorporates trait-associated single nucleotide polymorphism marker discovery,low-cost genotyping through amplicon sequencing(AmpSeq)and decision making.The results document the development of a MAS package derived from genotyping-by-sequencing using three traits(flower sex,disease resistance and acylated anthocyanins)in grapevine breeding.The vast majority of sequence reads(⩾99%)were from the targeted regions.Across 380 individuals and up to 31 amplicons sequenced in each lane of MiSeq data,most amplicons(83 to 87%)had<10%missing data,and read depth had a median of 220–244×.Several strengths of the AmpSeq platform that make this approach of broad interest in diverse crop species include accuracy,flexibility,speed,high-throughput,low-cost and easily automated analysis.展开更多
Background:Alfalfa is a globally important forage crop.Cultivars are characterized by fall dormancy(FD).FD affects biomass yield and winter survival and is used to identify appropriate growing regions of cultivars.It ...Background:Alfalfa is a globally important forage crop.Cultivars are characterized by fall dormancy(FD).FD affects biomass yield and winter survival and is used to identify appropriate growing regions of cultivars.It has historically been assessed by measuring the natural height of regrowth in autumn of spaced plants in the field.Because commercial alfalfa is normally grown as a solid planted sward,FD could be different if plants were grown under real production conditions.The objective of this experiment was to assess whether FD ratings obtained from swards were similar to those obtained on spaced plants.Methods:We evaluated 20 alfalfa cultivars in field trials established in 2015 at five locations in the United States.We harvested the trials in early autumn and measured regrowth plant height approximately 3 weeks later in 2015 and 2016.Results:Autumn plant height responded as expected for the established check cultivars in all locations.Fall dormancy ratings for cultivars under both management systems were highly correlated.Conclusions:Estimating FD from spaced plant height measurements in autumn is very robust,and using height data from sward plots gives equivalent results to that measured in spaced plant nurseries.This finding has many practical advantages.展开更多
Nutrient deficiencies in crops are a serious threat to human health,especially for populations in poor areas.To overcome this problem,the development of crops with nutrient-enhanced traits is imperative.Biofortificati...Nutrient deficiencies in crops are a serious threat to human health,especially for populations in poor areas.To overcome this problem,the development of crops with nutrient-enhanced traits is imperative.Biofortification of crops to improve nutritional quality helps combat nutrient deficiencies by increasing the levels of specific nutrient components.Compared with agronomic practices and conventional plant breeding,plant metabolic engineering and synthetic biology strategies are more effective and accurate in synthesizing specific micronutrients,phytonutrients,and/or bioactive components in crops.In this review,we discuss recent progress in the field of plant synthetic metabolic engineering,specifically in terms of research strategies of multigene stacking tools and engineering complex metabolic pathways,with a focus on improving traits related to micronutrients,phytonutrients,and bioactive components.Advances and innovations in plant synthetic metabolic engineering would facilitate the development of nutrient-enriched crops to meet the nutritional needs of humans.展开更多
Background Boron(B)deficiency is an important factor for poor seed cotton yield and fiber quality.However,it is often missing in the plant nutrition program,particularly in developing countries.The current study inves...Background Boron(B)deficiency is an important factor for poor seed cotton yield and fiber quality.However,it is often missing in the plant nutrition program,particularly in developing countries.The current study investigated B’s effect on growth,yield,and fiber quality of Bt(CIM-663)and non-Bt(Cyto-124)cotton cultivars.The experimental plan consisted of twelve treatments:Control(CK);B at 1 mg·kg^(−1) soil application(SB1);2 mg·kg^(−1) B(SB2);3 mg·kg^(−1) B(SB3);0.2%B foliar spray(FB1);0.4%B foliar spray(FB2);1 mg·kg^(−1) B+0.2%B foliar spray(SB1+FB1);1 mg·kg^(−1) B+0.4%B foliar spray(SB1+FB2);2 mg·kg^(−1) B+0.2%B foliar spray(SB2+FB1);2 mg·kg^(−1) B+0.4%B foliar spray(SB2+FB2);3 mg·kg^(−1) B+0.2%B foliar spray(SB3+FB1);3 mg·kg^(−1) B+0.4%B foliar spray(SB3+FB2).Each treat-ment has three replications,one pot having two plants per replication.Results B nutrition at all levels and methods of application significantly(P≤0.05)affected the growth,physiological,yield,and fiber quality characteristics of both cotton cultivars.However,SB2 either alone or in combination with foliar spray showed superiority over others,particularly in the non-Bt cultivar which responded better to B nutrition.Maxi-mum improvement in monopodial branches(345%),sympodial branches(143%),chlorophyll-a(177%),chlorophyll-b(194%),photosynthesis(169%),and ginning out turn(579%)in the non-Bt cultivar was found with SB2 compared with CK.In Bt cultivar,although no consistent trend was found but integrated use of SB3 with foliar spray performed relatively better for improving cotton growth compared with other treatments.Fiber quality characteristics in both cultivars were improved markedly but variably with different B treatments.Conclusion B nutrition with SB2 either alone or in combination with foliar spray was found optimum for improving cotton’s growth and yield characteristics.展开更多
Chromoplasts are colored plastids that synthesize and store massive amounts of carotenoids.Chromoplast number and size define the sink strength for carotenoid accumulation in plants.However,nothing is known about the ...Chromoplasts are colored plastids that synthesize and store massive amounts of carotenoids.Chromoplast number and size define the sink strength for carotenoid accumulation in plants.However,nothing is known about the mechanisms controlling chromoplast number.Previously,a natural allele of Orange(OR),OR^His,was found to promote carotenoid accumulation by activating chromoplast differentiation and increasing carotenoid biosynthesis,but cells in orange tissues in melon fruit and cauliflower OR mutant have only one or two enlarged chromoplasts.In this study,we investigated an OR^His variant of Arabidopsis OR,genetically mimicking the melon OR^His allele,and found that it also constrains chromoplast number in Arabidopsis calli.Both in vitro and in vivo experiments demonstrate that OR^His specifically interacts with the Membrane Occupation and Recognition Nexus domain of ACCUMULATION AND REPLICATION OF CHLOROPLASTS 3(ARC3),a crucial regulator of chloroplast division.We further showed that OR^His interferes with the interaction between ARC3 and PARALOG OF ARC6(PARC6),another key regulator of chloroplast division,suggesting a role of OR^His in competing with PARC6 for binding to ARC3 to restrict chromoplast number.Overexpression or knockout of ARC3 in Arabidopsis OR^His plants significantly alters total carotenoid levels.Moreover,overexpression of the plastid division factor PLASTID DIVISION 1 greatly enhances carotenoid accumulation.These division factors likely alter carotenoid levels via their influence on chromoplast number and/or size.Taken together,our findings provide novel mechanistic insights into the machinery controlling chromoplast number and highlight a potential new strategy for enhancing carotenoid accumulation and nutritional value in food crops.展开更多
Chlorophylls and carotenoids are essential photosynthetic pigments.Plants spatiotemporally coordinate the needs of chlorophylls and carotenoids for optimal photosynthesis and fitness in response to diverse environment...Chlorophylls and carotenoids are essential photosynthetic pigments.Plants spatiotemporally coordinate the needs of chlorophylls and carotenoids for optimal photosynthesis and fitness in response to diverse environmental and developmental cues.However,how the biosynthesis pathways of these two pigments are coordinated,particularly at posttranslational level to allow rapid control,remains largely unknown.Here,we report that the highly conserved ORANGE(OR)family proteins coordinate both pathways via posttranslationally mediating the first committed enzyme in each pathway.We demonstrate that OR family proteins physically interact with magnesium chelatase subunit I(CHLI)in chlorophyll biosynthesis pathway in addition to phytoene synthase(PSY)in carotenoid biosynthesis pathway and concurrently stabilize CHLI and PSY enzymes.We show that loss of OR genes hinders both chlorophyll and carotenoid biosynthesis,limits light-harvesting complex assembly,and impairs thylakoid grana stacking in chloroplasts.Overexpression of OR safeguards photosynthetic pigment biosynthesis and enhances thermotolerance in both Arabidopsis and tomato plants.Our findings establish a novel mechanism by which plants coordinate chlorophyll and carotenoid biosynthesis and provide a potential genetic target to generate climate-resilient crops.展开更多
Carotenoids,such asβ-carotene,accumulate in chromoplasts of various fleshy fruits,awarding them with colors,aromas,and nutrients.The Orange(CmOr)gene controlsβ-carotene accumulation in melon fruit by posttranslation...Carotenoids,such asβ-carotene,accumulate in chromoplasts of various fleshy fruits,awarding them with colors,aromas,and nutrients.The Orange(CmOr)gene controlsβ-carotene accumulation in melon fruit by posttranslationally enhancing carotenogenesis and repressingβ-carotene turnover in chromoplasts.Carotenoid isomerase(CRTISO)isomerizes yellow prolycopene into red lycopene,a prerequisite for further metabolism intoβ-carotene.We comparatively analyzed the developing fruit transcriptomes of orange-colored melon and its two isogenic EMS-induced mutants,low-β(Cmor)and yofi(Cmcrtiso).The Cmor mutation in low-βcaused a major transcriptomic change in the mature fruit.In contrast,the Cmcrtiso mutation in yofi significantly changed the transcriptome only in early fruit developmental stages.These findings indicate that melon fruit transcriptome is primarily altered by changes in carotenoid metabolic flux and plastid conversion,but minimally by carotenoid composition in the ripe fruit.Clustering of the differentially expressed genes into functional groups revealed an association between fruit carotenoid metabolic flux with the maintenance of the photosynthetic apparatus in fruit chloroplasts.Moreover,large numbers of thylakoid localized photosynthetic genes were differentially expressed in low-β.CmOR family proteins were found to physically interact with light-harvesting chlorophyll a–b binding proteins,suggesting a new role of CmOR for chloroplast maintenance in melon fruit.This study brings more insights into the cellular and metabolic processes associated with fruit carotenoid accumulation in melon fruit and reveals a new maintenance mechanism of the photosynthetic apparatus for plastid development.展开更多
The abundance of predatory phytoseiid mites,Typhlodromus pyri,important biological control agents of spider mite pests in numerous crops,is positively influenced by the density of leaf trichomes and tuft-form domatia ...The abundance of predatory phytoseiid mites,Typhlodromus pyri,important biological control agents of spider mite pests in numerous crops,is positively influenced by the density of leaf trichomes and tuft-form domatia in vein axils.Identification of the genetic regions controlling both trophic levels could facilitate the improvement of predatory mite habitat in breeding programs.The abundance of T.pyri and non-glandular trichomes was measured in a segregating F1 family derived from the cross of the complex Vitis hybrid,‘Horizon’,with Illinois 547-1(V.rupestris B38×V.cinerea B9),finding positive correlation among traits.High density genetic maps were used to localize one major quantitative trait locus(QTL)on chromosome 1 of Illinois 547-1 associated with both predatory mite abundance and leaf trichomes.This QTL explained 23%of the variation in phytoseiid abundance and similar amounts of variance in domatia rating(21%),domatia size(16%),leaf bristle density(37%in veins and 33%in blades),and leaf hair density(20%in veins and 15%in blades).Another nine QTL distributed among chromosomes 1,2,5,8,and 15 were associated solely with trichome density,and explained 7–17%of the phenotypic variation.Combined,our results provide evidence of the genetic architecture of non-glandular trichomes in Vitis,with a major locus influencing trichome densities,domatia size and predatory mite abundance.This information is relevant for breeding grapevines with a more favorable habitat for biological control agents.展开更多
Use of CRISPR-Cas9(Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)-CRISPR-associated 9)-mediated genome editing has proliferated for use in numerous plant species to modify gene function and expressi...Use of CRISPR-Cas9(Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)-CRISPR-associated 9)-mediated genome editing has proliferated for use in numerous plant species to modify gene function and expression,usually in the context of either transient or stably inherited genetic alternations.While extremely useful in many applications,modification of some loci yields outcomes detrimental to further experimental evaluation or viability of the target organism.Expression of Cas9 under a promoter conferring gene knockouts in a tissue-specific subset of genomes has been demonstrated in insect and animal models,and recently in Arabidopsis.We developed an in planta GFP(green fluorescent protein)assay system to demonstrate fruit-specific gene editing in tomato using a phosphoenolpyruvate carboxylase 2 gene promoter.We then targeted a SET-domain containing polycomb protein,SlEZ2,previously shown to yield pleiotropic phenotypes when targeted via ^(35)S-driven RNA interference and we were able to characterize fruit phenotypes absent additional developmental perturbations.Tissue-specific gene editing will have applications in assessing function of essential genes otherwise difficult to study via germline modifications and will provide routes to edited genomes in tissues that could not otherwise be recovered when their germline modification perturbs their normal development.展开更多
Staple grains with low levels of provitamin A carotenoids contribute to the global prevalence of vitamin A deficiency and therefore are the main targets for provitamin A biofortification.However,carotenoid stability d...Staple grains with low levels of provitamin A carotenoids contribute to the global prevalence of vitamin A deficiency and therefore are the main targets for provitamin A biofortification.However,carotenoid stability during both seed maturation and postharvest storage is a serious concern for the full benefits of carotenoid biofortified grains.In this study,we utilized Arabidopsis as a model to establish car-otenoid biofortification strategies in seeds.We discovered that manipulation of carotenoid biosynthetic activity by seed-specific expression of Phytoene synthase(PSY)increases both provitamin A and total carotenoid levels but the increased carotenoids are prone to degradation during seed maturation and storage,consistent with previous studies of provitamin A biofortified grains.In contrast,stacking with Orange(OR^(His)),a gene that initiates chromopl ast biogenesis,dramatically enhances provitamin A and total carotenoid content and stability.Up to 65-and 10-fold increases of β-carotene and total car-otenoids,res pectively,with provitamin A carotenoids composing over 63%were observed in the seeds containing OR^(His) and PSY.Co-expression of Homogen tisate geranylgeranyl transferase(HGGT)with OR^(His) and PSY further increases carotenoid accumulation and stability during seed maturation and storage.Moreover,knocking-out of B-carotene hydroxylase 2(BCH2)by CRISPR/Cas9 not only potentially facilitates β-carotene accumulation but also minimizes the negative effect of carotenoid over production on seed germi nation.Our findings provide new insights into various processes on carotenoid accu-mulation and stability in seeds and establish a multiplexed strategy to simultaneously target carotenoid biosynthesis,turnover,and stable storage for carotenoid biofortification in crop seeds.展开更多
This study determined the effects of genotype-by-environment(G × E) interaction and stability of yield among elite cowpea(Vigna unguiculata L.) selections derived by gamma irradiation. The study was conducted in ...This study determined the effects of genotype-by-environment(G × E) interaction and stability of yield among elite cowpea(Vigna unguiculata L.) selections derived by gamma irradiation. The study was conducted in Namibia at three selected sites: Bagani, Mannheim,and Omahenene, during 2014/2015 and 2015/2016. Thirty-four newly developed mutant genotypes and three local checks were evaluated using a randomized complete block design with three replications. Grain yield data were analyzed using the additive main effects and multiplicative interaction(AMMI) and the genotype main effect plus genotype-by-environment interaction(GGE) biplot methods. The AMMI and GGE biplot models explained 77.49% and 75.57% of total observed genotypic variation, respectively.Bagani and Omahenene were the environments best discriminating the test genotypes during 2014/2015 and 2015/2016, respectively. Four promising mutant genotypes: G9(Sh L3 P74), G10(Sh R3 P4), G12(Sh R9 P5), and G4(Sh L2 P4), showed wide adaptation and grain yields of 2.83, 2.06, 1.99, and 1.95 t ha^(-1), respectively. The novel mutant lines are useful genetic resources for production or future cowpea breeding programs in Namibia or similar environments.展开更多
Globally,pea(Pisum sativum L.)is an important temperate legume crop for food,feed and fodder,and many breeding programs develop cultivars adapted to these end-uses.In order to assist pea development efforts,we assembl...Globally,pea(Pisum sativum L.)is an important temperate legume crop for food,feed and fodder,and many breeding programs develop cultivars adapted to these end-uses.In order to assist pea development efforts,we assembled the USDA Pea Single Plant Plus Collection(PSPPC),which contains 431 P.sativum accessions with morphological,geographic and taxonomic diversity.The collection was characterized genetically in order to maximize its value for trait mapping and genomics-assisted breeding.To that end,we used genotyping-by-sequencing—a cost-effective method for de novo single-nucleotide polymorphism(SNP)marker discovery—to generate 66591 high-quality SNPs.These data facilitated the identification of accessions divergent from mainstream breeding germplasm that could serve as sources of novel,favorable alleles.In particular,a group of accessions from Central Asia appear nearly as diverse as a sister species,P.fulvum,and subspecies,P.sativum subsp.elatius.PSPPC genotypes can be paired with new and existing phenotype data for trait mapping;as proof-of-concept,we localized Mendel’s A gene controlling flower color to its known position.We also used SNP data to define a smaller core collection of 108 accessions with similar levels of genetic diversity as the entire PSPPC,resulting in a smaller germplasm set for research screening and evaluation under limited resources.Taken together,the results presented in this study along with the release of a publicly available SNP data set comprise a valuable resource for supporting worldwide pea genetic improvement efforts.展开更多
This work aims to screen mutant rice lines tolerant to Striga asiatica.Two rainfed sensitive rice varieties B22 and F154 were used.Plants survival rates of the two parents were significantly lower respectively(9.74a a...This work aims to screen mutant rice lines tolerant to Striga asiatica.Two rainfed sensitive rice varieties B22 and F154 were used.Plants survival rates of the two parents were significantly lower respectively(9.74a and 11.83a)than those of mutant lines(55.36c to 74.36b);Striga plants emergence/pot were significantly higher for the parents(13.96c and14.89c)compared to the mutants(0.12a to 1.5b);the infection rate of parents(7.37b;7.86b)was higher compared to the mutants(2.27a to 2.74a);fertility rate/plant of parents was lower(20.98%b;22.29%b)but much higher than mutants(72.19%b to 78.35%b);the average panicle number/plant of parents was significantly lower(0.5a;1a)than those of mutants(1.5b to 2.4bc)and the 100 g grain weight of parents are lower(2.35a;2.56a)than those of mutants(3.19b to 3.23b).The culture of those mutant lines may increase rice production and contribute to enhancing food security in Madagascar.展开更多
文摘Carotenoids are a diverse group of pigments widely distributed in nature.The vivid yellow,orange,and red colors of many horticultural crops are attributed to the overaccumulation of carotenoids,which contribute to a critical agronomic trait for flowers and an important quality trait for fruits and vegetables.Not only do carotenoids give horticultural crops their visual appeal,they also enhance nutritional value and health benefits for humans.As a result,carotenoid research in horticultural crops has grown exponentially over the last decade.These investigations have advanced our fundamental understanding of carotenoid metabolism and regulation in plants.In this review,we provide an overview of carotenoid biosynthesis,degradation,and accumulation in horticultural crops and highlight recent achievements in our understanding of carotenoid metabolic regulation in vegetables,fruits,and flowers.
文摘Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. These plastids have dramatic differences in their capacity to synthesize and sequester carotenoids. Clearly, plastids play a central role in governing carotenogenic activity, carotenoid stability, and pigment diversity. Understanding of carotenoid metabolism and accumulation in various plastids expands our view on the multifaceted regulation of carotenogenesis and facilitates our efforts toward developing nutrient-enriched food crops. In this review, we provide a comprehensive overview of the impact of various types of plastids on carotenoid biosynthesis and accumulation, and discuss recent advances in our understanding of the regulatory control of carotenogenesis and metabolic engineering of carotenoids in light of plastid types in plants.
基金We thank current and pastmembers of our laboratory and collaborators for their contribution to some of the work described here.This work was supported by the Agriculture and Food Research Initiative competitive award(Grant No.2019-67013-29162)from the USDA National Institute of Food and Agriculture,the United States-Israel Binational Agricultural Research and Development Fund(Grant No.US-4918-16CR)the USDA-ARS base fund.
文摘Carotenoids are a group of widely distributed natural pigments.They give many horticultural plants the bright red,orange,and yellow colors,as well as the aroma and flavor.Carotenoids enhance the health value and represent an essential quality trait of horticultural products.Significant efforts have been made to correlate specific carotenoid production with pathway gene expression.Some transcription factors that directly regulate transcription of the pathway genes have been identified.Horticultural crops have evolved with complicated and multifaceted regulatory mechanisms to generate the enormous diversity in carotenoid content and composition.However,the diverse and complex control of carotenoid accumulation is still not well understood.In this review,we depict carotenoid accumulation pathways and highlight the recent progress in the regulatory control of carotenoid accumulation in horticultural plants.Because of the critical roles of chromoplasts for carotenoid hyperproduction,we evaluate chromoplast ultrastructures and carotenoid sequestrations.A perspective on carotenoid research in horticultural crops is provided.
文摘Phytoene synthase （PSY） is the crucial plastidial enzyme in the carotenoid biosynthetic pathway. However, its post-translational regulation remains elusive. Likewise, Clp protease constitutes a central part of the plastid protease network, but its substrates for degradation are not well known. In this study, we report that PSY is a substrate of the Clp protease. PSY was uncovered to physically interact with various Clp protease subunits （i.e., ClpS1, CIpC1, and CIpD）. High levels of PSY and several other carotenogenic enzyme proteins overac- cumulate in the clpcl, clpp4, and clprl-2 mutants. The overaccumulated PSY was found to be partially enzy- matically active. Impairment of Clp activity in clpcl results in a reduced rate of PSY protein turnover, further supporting the role of Clp protease in degrading PSY protein. On the other hand, the ORANGE （OR） protein, a major post-translational regulator of PSY with holdase chaperone activity, enhances PSY protein stability and increases the enzymatically active proportion of PSY in clpcl, counterbalancing CIp-mediated proteol- ysis in maintaining PSY protein homeostasis. Collectively, these findings provide novel insights into the qual- ity control of plastid-localized proteins and establish a hitherto unidentified post-translational regulatory mechanism of carotenogenic enzymes in modulating carotenoid biosynthesis in plants.
基金supported by the National Natural Science Foundation of China(81973422 and 31570302)the Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(2021-I2M-1-071).
文摘Artemisia argyi Le´vl.et Vant.,a perennial Artemisia herb with an intense fragrance,is widely used in traditional medicine in China and many other Asian countries.Here,we present a chromosome-scale genome assembly of A.argyi comprising 3.89 Gb assembled into 17 pseudochromosomes.Phylogenetic and comparative genomic analyses revealed that A.argyi underwent a recent lineage-specificwhole-genomeduplication(WGD)event after divergence fromArtemisia annua,resulting in two subgenomes.Wedeciphered the diploid ancestral genome of A.argyi,and unbiased subgenome evolution was observed.The recent WGD led to a large number of duplicated genes in the A.argyi genome.Expansion of the terpene synthase(TPS)gene family through various types of gene duplication may have greatly contributed to the diversity of volatile terpenoids in A.argyi.In particular,we identified a typical germacrene D synthase gene cluster within the expanded TPS gene family.The entire biosynthetic pathways of germacrenes,(+)-borneol,and(+)-camphor were elucidated in A.argyi.In addition,partial deletion of the amorpha-4,11-diene synthase(ADS)gene and loss of function of ADS homologs may have resulted in the lack of artemisinin production in A.argyi.Our study provides newinsights into the genome evolution of Artemisia and lays a foundation for further improvement of the quality of this important medicinal plant.
基金This work was supported by Agriculture and Food Research Initiative competitive award grant no.2019-67013-29162(to LL)and 2021-67013-33841(to LL and TS)from the USDA National Institute of Food and Agriculture and USDA-ARS base fund.
文摘Carotenoids are isoprenoid metabolites synthesized de novo in all photosynthetic organisms.Carotenoids are essential for plants with diverse functions in photosynthesis,photoprotection,pigmentation,phytohormone synthesis,and signaling.They are also critically important for humans as precursors of vitamin A synthesis and as dietary antioxidants.The vital roles of carotenoids to plants and humans have prompted significant progress toward our understanding of carotenoid metabolism and regulation.New regulators and novel roles of carotenoid metabolites are continuously revealed.This review focuses on current status of carotenoid metabolism and highlights recent advances in comprehension of the intrinsic and multi-dimensional regulation of carotenoid accumulation.We also discuss the functional evolution of carotenoids,the agricultural and horticultural application,and some key areas for future research.
基金supported by the Major Special Projects and Key R&D Projects in Yunnan Province,China(202102AE090054)the National Natural Science Foundation of China(31925034)+1 种基金the Foundation of Hubei Hongshan Laboratory granted to Dr.Qiang Xu,China(2021hszd016)the Key Project of Hubei Provincial Natural Science Foundation,China(2021CFA017)。
文摘The flesh color of pummelo(Citrus maxima)fruits is highly diverse and largely depends on the level of carotenoids,which are beneficial to human health.It is vital to investigate the regulatory network of carotenoid biosynthesis to improve the carotenoid content in pummelo.However,the molecular mechanism underlying carotenoid accumulation in pummelo is not fully understood.In this study,we identified a novel histone methyltransferase gene,CgSDG40,involved in carotenoid regulation by analyzing the flesh transcriptome of typical white-fleshed pummelo,red-fleshed pummelo and extreme-colored F1 hybrids from a segregated pummelo population.Expression of CgSDG40 corresponded to flesh color change and was highly coexpressed with CgPSY1.Interestingly,CgSDG40 and CgPSY1 are located physically adjacent to each other on the chromosome in opposite directions,sharing a partially overlapping promoter region.Subcellular localization analysis indicated that CgSDG40 localizes to the nucleus.Overexpression of CgSDG40 significantly increased the total carotenoid content in citrus calli relative to that in wild type.In addition,expression of CgPSY1 was significantly activated in overexpression lines relative to wild type.Taken together,our findings reveal a novel histone methyltransferase regulator,CgSDG40,involved in the regulation of carotenoid biosynthesis in citrus and provide new strategies for molecular design breeding and genetic improvement of fruit color and nutritional quality.
基金The US Department of Agriculture National Institute of Food and Agriculture Specialty Crop Research Initiative provided funding for this project(award no.2011-51181-30635).
文摘Marker-assisted selection(MAS)is often employed in crop breeding programs to accelerate and enhance cultivar development,via selection during the juvenile phase and parental selection prior to crossing.Next-generation sequencing and its derivative technologies have been used for genome-wide molecular marker discovery.To bridge the gap between marker development and MAS implementation,this study developed a novel practical strategy with a semi-automated pipeline that incorporates trait-associated single nucleotide polymorphism marker discovery,low-cost genotyping through amplicon sequencing(AmpSeq)and decision making.The results document the development of a MAS package derived from genotyping-by-sequencing using three traits(flower sex,disease resistance and acylated anthocyanins)in grapevine breeding.The vast majority of sequence reads(⩾99%)were from the targeted regions.Across 380 individuals and up to 31 amplicons sequenced in each lane of MiSeq data,most amplicons(83 to 87%)had<10%missing data,and read depth had a median of 220–244×.Several strengths of the AmpSeq platform that make this approach of broad interest in diverse crop species include accuracy,flexibility,speed,high-throughput,low-cost and easily automated analysis.
文摘Background:Alfalfa is a globally important forage crop.Cultivars are characterized by fall dormancy(FD).FD affects biomass yield and winter survival and is used to identify appropriate growing regions of cultivars.It has historically been assessed by measuring the natural height of regrowth in autumn of spaced plants in the field.Because commercial alfalfa is normally grown as a solid planted sward,FD could be different if plants were grown under real production conditions.The objective of this experiment was to assess whether FD ratings obtained from swards were similar to those obtained on spaced plants.Methods:We evaluated 20 alfalfa cultivars in field trials established in 2015 at five locations in the United States.We harvested the trials in early autumn and measured regrowth plant height approximately 3 weeks later in 2015 and 2016.Results:Autumn plant height responded as expected for the established check cultivars in all locations.Fall dormancy ratings for cultivars under both management systems were highly correlated.Conclusions:Estimating FD from spaced plant height measurements in autumn is very robust,and using height data from sward plots gives equivalent results to that measured in spaced plant nurseries.This finding has many practical advantages.
基金This work was supported by grants from the National Natural Science Foundation of China(31971915)the Major Program of Guangdong Basic and Applied Research(2019B030302006).
文摘Nutrient deficiencies in crops are a serious threat to human health,especially for populations in poor areas.To overcome this problem,the development of crops with nutrient-enhanced traits is imperative.Biofortification of crops to improve nutritional quality helps combat nutrient deficiencies by increasing the levels of specific nutrient components.Compared with agronomic practices and conventional plant breeding,plant metabolic engineering and synthetic biology strategies are more effective and accurate in synthesizing specific micronutrients,phytonutrients,and/or bioactive components in crops.In this review,we discuss recent progress in the field of plant synthetic metabolic engineering,specifically in terms of research strategies of multigene stacking tools and engineering complex metabolic pathways,with a focus on improving traits related to micronutrients,phytonutrients,and bioactive components.Advances and innovations in plant synthetic metabolic engineering would facilitate the development of nutrient-enriched crops to meet the nutritional needs of humans.
文摘Background Boron(B)deficiency is an important factor for poor seed cotton yield and fiber quality.However,it is often missing in the plant nutrition program,particularly in developing countries.The current study investigated B’s effect on growth,yield,and fiber quality of Bt(CIM-663)and non-Bt(Cyto-124)cotton cultivars.The experimental plan consisted of twelve treatments:Control(CK);B at 1 mg·kg^(−1) soil application(SB1);2 mg·kg^(−1) B(SB2);3 mg·kg^(−1) B(SB3);0.2%B foliar spray(FB1);0.4%B foliar spray(FB2);1 mg·kg^(−1) B+0.2%B foliar spray(SB1+FB1);1 mg·kg^(−1) B+0.4%B foliar spray(SB1+FB2);2 mg·kg^(−1) B+0.2%B foliar spray(SB2+FB1);2 mg·kg^(−1) B+0.4%B foliar spray(SB2+FB2);3 mg·kg^(−1) B+0.2%B foliar spray(SB3+FB1);3 mg·kg^(−1) B+0.4%B foliar spray(SB3+FB2).Each treat-ment has three replications,one pot having two plants per replication.Results B nutrition at all levels and methods of application significantly(P≤0.05)affected the growth,physiological,yield,and fiber quality characteristics of both cotton cultivars.However,SB2 either alone or in combination with foliar spray showed superiority over others,particularly in the non-Bt cultivar which responded better to B nutrition.Maxi-mum improvement in monopodial branches(345%),sympodial branches(143%),chlorophyll-a(177%),chlorophyll-b(194%),photosynthesis(169%),and ginning out turn(579%)in the non-Bt cultivar was found with SB2 compared with CK.In Bt cultivar,although no consistent trend was found but integrated use of SB3 with foliar spray performed relatively better for improving cotton growth compared with other treatments.Fiber quality characteristics in both cultivars were improved markedly but variably with different B treatments.Conclusion B nutrition with SB2 either alone or in combination with foliar spray was found optimum for improving cotton’s growth and yield characteristics.
基金This work was supported by Agriculture and Food Research Initiative competitive awards grant nos.2016-67013-24612 and 2019-67013-29162 from the United States Department of Agriculture National Institute of Food and Agriculture.C.Cwas supported by the United States Department of Energy,Office of Science,Basic Energy Sciences award number DE-FG02-06ER15808 to K.W.O.
文摘Chromoplasts are colored plastids that synthesize and store massive amounts of carotenoids.Chromoplast number and size define the sink strength for carotenoid accumulation in plants.However,nothing is known about the mechanisms controlling chromoplast number.Previously,a natural allele of Orange(OR),OR^His,was found to promote carotenoid accumulation by activating chromoplast differentiation and increasing carotenoid biosynthesis,but cells in orange tissues in melon fruit and cauliflower OR mutant have only one or two enlarged chromoplasts.In this study,we investigated an OR^His variant of Arabidopsis OR,genetically mimicking the melon OR^His allele,and found that it also constrains chromoplast number in Arabidopsis calli.Both in vitro and in vivo experiments demonstrate that OR^His specifically interacts with the Membrane Occupation and Recognition Nexus domain of ACCUMULATION AND REPLICATION OF CHLOROPLASTS 3(ARC3),a crucial regulator of chloroplast division.We further showed that OR^His interferes with the interaction between ARC3 and PARALOG OF ARC6(PARC6),another key regulator of chloroplast division,suggesting a role of OR^His in competing with PARC6 for binding to ARC3 to restrict chromoplast number.Overexpression or knockout of ARC3 in Arabidopsis OR^His plants significantly alters total carotenoid levels.Moreover,overexpression of the plastid division factor PLASTID DIVISION 1 greatly enhances carotenoid accumulation.These division factors likely alter carotenoid levels via their influence on chromoplast number and/or size.Taken together,our findings provide novel mechanistic insights into the machinery controlling chromoplast number and highlight a potential new strategy for enhancing carotenoid accumulation and nutritional value in food crops.
基金supported by Agriculture and Food Research Initiative competitive award grant no.2019-67013-29162(to L.L.)and 2021-67013-33841(to L.L.and T.S.)from the USDA National Institute of Food and Agriculture,USDA-ARS fundthe Research Grants Council of Hong Kong(Early Career Scheme 27118022)The University of Hong Kong(the Seed Fund 20211115918)to P.W.and the Deutsche Forschungsgemeinschaft to P.W.(WA 4599/2-2)and to B.G.(FOR2092,GR 936/18-1,and SFB TRR175,subproject C04).
文摘Chlorophylls and carotenoids are essential photosynthetic pigments.Plants spatiotemporally coordinate the needs of chlorophylls and carotenoids for optimal photosynthesis and fitness in response to diverse environmental and developmental cues.However,how the biosynthesis pathways of these two pigments are coordinated,particularly at posttranslational level to allow rapid control,remains largely unknown.Here,we report that the highly conserved ORANGE(OR)family proteins coordinate both pathways via posttranslationally mediating the first committed enzyme in each pathway.We demonstrate that OR family proteins physically interact with magnesium chelatase subunit I(CHLI)in chlorophyll biosynthesis pathway in addition to phytoene synthase(PSY)in carotenoid biosynthesis pathway and concurrently stabilize CHLI and PSY enzymes.We show that loss of OR genes hinders both chlorophyll and carotenoid biosynthesis,limits light-harvesting complex assembly,and impairs thylakoid grana stacking in chloroplasts.Overexpression of OR safeguards photosynthetic pigment biosynthesis and enhances thermotolerance in both Arabidopsis and tomato plants.Our findings establish a novel mechanism by which plants coordinate chlorophyll and carotenoid biosynthesis and provide a potential genetic target to generate climate-resilient crops.
基金the United States-Israel Binational Agricultural Research and Development Fund(grant no.US-4918-16CR)the Agriculture and Food Research Initiative competitive award(grant no.2019-67013-29162)from the USDA National Institute of Food and Agriculture,and the USDA-ARS fund.
文摘Carotenoids,such asβ-carotene,accumulate in chromoplasts of various fleshy fruits,awarding them with colors,aromas,and nutrients.The Orange(CmOr)gene controlsβ-carotene accumulation in melon fruit by posttranslationally enhancing carotenogenesis and repressingβ-carotene turnover in chromoplasts.Carotenoid isomerase(CRTISO)isomerizes yellow prolycopene into red lycopene,a prerequisite for further metabolism intoβ-carotene.We comparatively analyzed the developing fruit transcriptomes of orange-colored melon and its two isogenic EMS-induced mutants,low-β(Cmor)and yofi(Cmcrtiso).The Cmor mutation in low-βcaused a major transcriptomic change in the mature fruit.In contrast,the Cmcrtiso mutation in yofi significantly changed the transcriptome only in early fruit developmental stages.These findings indicate that melon fruit transcriptome is primarily altered by changes in carotenoid metabolic flux and plastid conversion,but minimally by carotenoid composition in the ripe fruit.Clustering of the differentially expressed genes into functional groups revealed an association between fruit carotenoid metabolic flux with the maintenance of the photosynthetic apparatus in fruit chloroplasts.Moreover,large numbers of thylakoid localized photosynthetic genes were differentially expressed in low-β.CmOR family proteins were found to physically interact with light-harvesting chlorophyll a–b binding proteins,suggesting a new role of CmOR for chloroplast maintenance in melon fruit.This study brings more insights into the cellular and metabolic processes associated with fruit carotenoid accumulation in melon fruit and reveals a new maintenance mechanism of the photosynthetic apparatus for plastid development.
基金supported by the Specialty Crop Research Initiative of the National Institute of Food and Agriculture,U.S.Department of Agriculture,under award number 2011-51181-30635 and National Research Initiative award number 2004-35302-14725.
文摘The abundance of predatory phytoseiid mites,Typhlodromus pyri,important biological control agents of spider mite pests in numerous crops,is positively influenced by the density of leaf trichomes and tuft-form domatia in vein axils.Identification of the genetic regions controlling both trophic levels could facilitate the improvement of predatory mite habitat in breeding programs.The abundance of T.pyri and non-glandular trichomes was measured in a segregating F1 family derived from the cross of the complex Vitis hybrid,‘Horizon’,with Illinois 547-1(V.rupestris B38×V.cinerea B9),finding positive correlation among traits.High density genetic maps were used to localize one major quantitative trait locus(QTL)on chromosome 1 of Illinois 547-1 associated with both predatory mite abundance and leaf trichomes.This QTL explained 23%of the variation in phytoseiid abundance and similar amounts of variance in domatia rating(21%),domatia size(16%),leaf bristle density(37%in veins and 33%in blades),and leaf hair density(20%in veins and 15%in blades).Another nine QTL distributed among chromosomes 1,2,5,8,and 15 were associated solely with trichome density,and explained 7–17%of the phenotypic variation.Combined,our results provide evidence of the genetic architecture of non-glandular trichomes in Vitis,with a major locus influencing trichome densities,domatia size and predatory mite abundance.This information is relevant for breeding grapevines with a more favorable habitat for biological control agents.
基金supported by National Science Foundation Plant Genome Program grant IOS-1855585 to JG and the US Department of Agriculture-Agricultural Research Service.
文摘Use of CRISPR-Cas9(Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)-CRISPR-associated 9)-mediated genome editing has proliferated for use in numerous plant species to modify gene function and expression,usually in the context of either transient or stably inherited genetic alternations.While extremely useful in many applications,modification of some loci yields outcomes detrimental to further experimental evaluation or viability of the target organism.Expression of Cas9 under a promoter conferring gene knockouts in a tissue-specific subset of genomes has been demonstrated in insect and animal models,and recently in Arabidopsis.We developed an in planta GFP(green fluorescent protein)assay system to demonstrate fruit-specific gene editing in tomato using a phosphoenolpyruvate carboxylase 2 gene promoter.We then targeted a SET-domain containing polycomb protein,SlEZ2,previously shown to yield pleiotropic phenotypes when targeted via ^(35)S-driven RNA interference and we were able to characterize fruit phenotypes absent additional developmental perturbations.Tissue-specific gene editing will have applications in assessing function of essential genes otherwise difficult to study via germline modifications and will provide routes to edited genomes in tissues that could not otherwise be recovered when their germline modification perturbs their normal development.
文摘Staple grains with low levels of provitamin A carotenoids contribute to the global prevalence of vitamin A deficiency and therefore are the main targets for provitamin A biofortification.However,carotenoid stability during both seed maturation and postharvest storage is a serious concern for the full benefits of carotenoid biofortified grains.In this study,we utilized Arabidopsis as a model to establish car-otenoid biofortification strategies in seeds.We discovered that manipulation of carotenoid biosynthetic activity by seed-specific expression of Phytoene synthase(PSY)increases both provitamin A and total carotenoid levels but the increased carotenoids are prone to degradation during seed maturation and storage,consistent with previous studies of provitamin A biofortified grains.In contrast,stacking with Orange(OR^(His)),a gene that initiates chromopl ast biogenesis,dramatically enhances provitamin A and total carotenoid content and stability.Up to 65-and 10-fold increases of β-carotene and total car-otenoids,res pectively,with provitamin A carotenoids composing over 63%were observed in the seeds containing OR^(His) and PSY.Co-expression of Homogen tisate geranylgeranyl transferase(HGGT)with OR^(His) and PSY further increases carotenoid accumulation and stability during seed maturation and storage.Moreover,knocking-out of B-carotene hydroxylase 2(BCH2)by CRISPR/Cas9 not only potentially facilitates β-carotene accumulation but also minimizes the negative effect of carotenoid over production on seed germi nation.Our findings provide new insights into various processes on carotenoid accu-mulation and stability in seeds and establish a multiplexed strategy to simultaneously target carotenoid biosynthesis,turnover,and stable storage for carotenoid biofortification in crop seeds.
基金supported by funds from the International Atomic Energy Agency (IAEA) through the TC Project (NAM5012): Developing High Yielding and Drought Tolerant Crops through Mutation Breeding) and the Ministry of Agriculture, Water and Forestry of Namibia
文摘This study determined the effects of genotype-by-environment(G × E) interaction and stability of yield among elite cowpea(Vigna unguiculata L.) selections derived by gamma irradiation. The study was conducted in Namibia at three selected sites: Bagani, Mannheim,and Omahenene, during 2014/2015 and 2015/2016. Thirty-four newly developed mutant genotypes and three local checks were evaluated using a randomized complete block design with three replications. Grain yield data were analyzed using the additive main effects and multiplicative interaction(AMMI) and the genotype main effect plus genotype-by-environment interaction(GGE) biplot methods. The AMMI and GGE biplot models explained 77.49% and 75.57% of total observed genotypic variation, respectively.Bagani and Omahenene were the environments best discriminating the test genotypes during 2014/2015 and 2015/2016, respectively. Four promising mutant genotypes: G9(Sh L3 P74), G10(Sh R3 P4), G12(Sh R9 P5), and G4(Sh L2 P4), showed wide adaptation and grain yields of 2.83, 2.06, 1.99, and 1.95 t ha^(-1), respectively. The novel mutant lines are useful genetic resources for production or future cowpea breeding programs in Namibia or similar environments.
基金Funding for WL Holdsworth was provided by Agriculture and Food Research Initiative Competitive Grant for Plant Breeding and Education no.2010-85117-20551 from the USDA National Institute of Food and AgricultureE Gazave was supported by USDA-NIFA/DOE Biomass Research and Development Initiative(BRDI)Proposal No.2011-06476(MA Gore)+1 种基金Funding for genotyping was provided by a USDA National Plant Germplasm System Evaluation Grant(M Mazourek)and the USA Dry Pea and Lentil Council Research Committee(RJ McGee,CJ Coyne)Publication costs were supported by a Barbara McClintock Award.
文摘Globally,pea(Pisum sativum L.)is an important temperate legume crop for food,feed and fodder,and many breeding programs develop cultivars adapted to these end-uses.In order to assist pea development efforts,we assembled the USDA Pea Single Plant Plus Collection(PSPPC),which contains 431 P.sativum accessions with morphological,geographic and taxonomic diversity.The collection was characterized genetically in order to maximize its value for trait mapping and genomics-assisted breeding.To that end,we used genotyping-by-sequencing—a cost-effective method for de novo single-nucleotide polymorphism(SNP)marker discovery—to generate 66591 high-quality SNPs.These data facilitated the identification of accessions divergent from mainstream breeding germplasm that could serve as sources of novel,favorable alleles.In particular,a group of accessions from Central Asia appear nearly as diverse as a sister species,P.fulvum,and subspecies,P.sativum subsp.elatius.PSPPC genotypes can be paired with new and existing phenotype data for trait mapping;as proof-of-concept,we localized Mendel’s A gene controlling flower color to its known position.We also used SNP data to define a smaller core collection of 108 accessions with similar levels of genetic diversity as the entire PSPPC,resulting in a smaller germplasm set for research screening and evaluation under limited resources.Taken together,the results presented in this study along with the release of a publicly available SNP data set comprise a valuable resource for supporting worldwide pea genetic improvement efforts.
文摘This work aims to screen mutant rice lines tolerant to Striga asiatica.Two rainfed sensitive rice varieties B22 and F154 were used.Plants survival rates of the two parents were significantly lower respectively(9.74a and 11.83a)than those of mutant lines(55.36c to 74.36b);Striga plants emergence/pot were significantly higher for the parents(13.96c and14.89c)compared to the mutants(0.12a to 1.5b);the infection rate of parents(7.37b;7.86b)was higher compared to the mutants(2.27a to 2.74a);fertility rate/plant of parents was lower(20.98%b;22.29%b)but much higher than mutants(72.19%b to 78.35%b);the average panicle number/plant of parents was significantly lower(0.5a;1a)than those of mutants(1.5b to 2.4bc)and the 100 g grain weight of parents are lower(2.35a;2.56a)than those of mutants(3.19b to 3.23b).The culture of those mutant lines may increase rice production and contribute to enhancing food security in Madagascar.
