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Angra, D.

Publications and source records attributed to Angra, D..

5 recordsLinked to original sources

Identification of QTLs linked to partial resistance to foot and root rot caused by Fusarium avenaceum and Fusarium oxysporum in faba bean (Vicia faba)

Foot and root rot, caused by a complex of soil-borne fungal and oomycete pathogens, including several Fusarium spp., can cause serious yield losses in faba bean. Current control strategies rely largely on agronomic practices and limited varietal resistance. Identifying novel sources of genetic resistance is of great potential value for breeding elite varieties with improved foot rot resistance. A partially resistant Vicia faba accession ig124213 (NV490) was crossed with a moderately susceptible ig124301 (NV512) and a mapping population comprising 198 F3 families was developed. This was screened for resistance to a mixture of seven UK field isolates of Fusarium avenaceum and Fusarium oxysporum under glasshouse conditions. Several F3 families with moderate to high levels of resistance to both Fusarium species were identified, and a high-density linkage map of the V. faba genome including 6755 SNP-markers in seven linkage groups (LG) was generated using the Vfaba_v2 Axiom SNP array. Quantitative trait loci associated with improved resistance to Fusarium foot and root rot were identified, including one major QTL on LG4, corresponding to the chromosome 4 of V. faba. Key messageThe first QTL associated with partial resistance to Fusarium foot and root rot has been identified using a biparental mapping population of Vicia faba.

plant biology↗

Genome-wide association studies identify promising QTL for freezing tolerance in winter and early spring as a basis for in-depth genetic analysis and implementation in winter faba bean (Vicia faba L.) breeding

Interest in faba bean as a locally adapted high-protein grain legume crop has increased in Europe over the past decade. Winter faba bean, which can make use of soil moisture from autumn to spring and partially escape summer droughts, exhibit greater yield potential than the spring-type. However, due to insufficient winter hardiness, winterkill is a major constraint that prevents large-scale production of current winter-type cultivars in Central and Northern Europe. Here, we extend the understanding of freezing tolerance, the main component trait of winter hardiness, during winter and against late-frost in early spring and define genomic target regions for marker-assisted selection. Comparative analysis of genome-wide association studies revealed 13 treatment-specific major QTLs with partially pleiotropic effect on four freezing tolerance related traits. In addition, we identified five treatment-unspecific pleiotropic QTLs, including two major freezing tolerance loci on chromosomes 1 and 5. Our results thus indicate both a distinct and common genetic control of tolerance to winter- and late-frost in winter faba bean. In combination with the promising prediction abilities obtained from marker score-based prediction, our work highlights the potential for marker-assisted and genomic selection toward improved freezing tolerance and winter hardiness in winter faba bean breeding programs.

genetics↗

The giant diploid faba genome unlocks variation in a global protein crop

Increasing the proportion of locally produced plant protein in currently meat-rich diets could substantially reduce greenhouse gas emission and loss of biodiversity. However, plant protein production is hampered by the lack of a cool-season legume equivalent to soybean in agronomic value. Faba bean (Vicia faba L.) has a high yield potential and is well-suited for cultivation in temperate regions, but genomic resources are scarce. Here, we report a high-quality chromosome-scale assembly of the faba bean genome and show that it has grown to a massive 13 Gb in size through an imbalance between the rates of amplification and elimination of retrotransposons and satellite repeats. Genes and recombination events are evenly dispersed across chromosomes and the gene space is remarkably compact considering the genome size, though with significant copy number variation driven by tandem duplication. Demonstrating practical application of the genome sequence, we develop a targeted genotyping assay and use high-resolution genome-wide association (GWA) analysis to dissect the genetic basis of hilum colour. The resources presented constitute a genomics-based breeding platform for faba bean, enabling breeders and geneticists to accelerate improvement of sustainable protein production across Mediterranean, subtropical, and northern temperate agro-ecological zones.

plant biology↗

Genetic analysis of global faba bean germplasm maps agronomic traits and identifies strong selection signatures for geographical origin

Faba bean (Vicia faba L.) is a high-protein grain legume crop with great potential for further cultivation. However, little is known about the genetics underlying trait diversity. In this study, we use 21,345 high-quality SNP markers to genetically characterise 2,678 faba bean genotypes. We perform genome-wide association studies of key agronomic traits using a Seven-parent-MAGIC population and detect 238 significant marker-trait associations linked to 12 traits of agronomic importance, with 65 of these being stable across multiple environments. Using a non-redundant diversity panel of 685 accessions from 52 countries, we identify 3 subpopulations differentiated by geographical origin and 33 genomic regions subject to strong diversifying selection between subpopulations. We find that SNP markers associated with the differentiation of northern and southern accessions were able to explain a significant proportion of agronomic trait variance in the Seven-parent-MAGIC population, suggesting that some of these traits have played an important role in breeding. Altogether, our findings point to genomic regions associated with important agronomic traits and selection in faba bean, which can be used for breeding purposes. Key MessageWe identified marker-trait associations for key faba bean agronomic traits and genomic signatures of selection within a global germplasm collection.

genetics↗

VC1 catalyzes a key step in the biosynthesis of vicine from GTP in faba bean

Faba bean is a widely adapted and high-yielding legume cultivated for its protein-rich seeds1. However, the seeds accumulate the anti-nutritional pyrimidine glucosides vicine and convicine, which can cause haemolytic anaemia--favism--in the 400 million individuals genetically predisposed by a deficiency in glucose-6-phosphate dehydrogenase2. Here, we identify the first enzyme associated with vicine and convicine biosynthesis, which we name VC1. We show that VC1 co-locates with the major QTL for vicine and convicine content and that the expression of VC1 correlates highly with vicine content across tissues. We also show that low-vicine varieties express a version of VC1 carrying a small, frame-shift insertion, and that overexpression of wild-type VC1 leads to an increase in vicine levels. VC1 encodes a functional GTP cyclohydrolase II, an enzyme normally involved in riboflavin biosynthesis from the purine GTP. Through feeding studies, we demonstrate that GTP is a precursor of vicine both in faba bean and in the distantly related plant bitter gourd. Our results reveal an unexpected biosynthetic origin for vicine and convicine and pave the way for the development of faba bean cultivars that are free from these anti-nutrients, providing a safe and sustainable source of dietary protein.

biochemistry↗