Publications by authors named "Walid Korani"

White mold, caused by the fungus Sclerotinia sclerotiorum (Lib.) de Bary, is a devastating disease affecting common bean (Phaseolus vulgaris L.) production worldwide.

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  • Groundnuts are vital oil crops in sub-Saharan Africa but face yield gaps due to soil issues and other stresses.
  • The study focused on assessing breeding lines in Uganda and Malawi to find high-yield genotypes for future use.
  • Results showed significant genetic variation in yield traits, with five stable genotypes identified as top performers, and marker-trait associations were mapped to assist in future breeding efforts.
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Gene discovery reveals new biology, expands the utility of marker-assisted selection, and enables targeted mutagenesis. Still, such discoveries can take over a decade. We present a general strategy, "Agile Genetics," that uses nested, structured populations to overcome common limits on gene resolution.

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Background: Aspergillus flavus is an important agricultural and food safety threat due to its production of carcinogenic aflatoxins. It has high level of genetic diversity that is adapted to various environments. Recently, we reported two reference genomes of A.

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White mold (WM), caused by the ubiquitous fungus Sclerotinia sclerotiorum, is a devastating disease that limits production and quality of dry bean globally. In the present study, classic linkage mapping combined with QTL-seq were employed in two recombinant inbred line (RIL) populations, "Montrose"/I9365-25 (M25) and "Raven"/I9365-31 (R31), with the initial goal of fine-mapping QTL WM5.4 and WM7.

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White mold (WM) is a major disease in common bean ( L.), and its complex quantitative genetic control limits the development of WM resistant cultivars. WM2.

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  • Narrow genetics in most crops poses a risk to food security, making wild crop relatives like GKP 10017 a crucial resource for enhancing genetic diversity and crop resilience.
  • Through genetic analysis, the study reveals how hybridization and seed exchanges since the 1960s have resulted in disease-resistant peanut cultivars across various continents, supporting global food security and economic growth.
  • The research highlights the need for international cooperation in germplasm access and warns that restrictive national laws threaten the benefits that could come from wild species in improving crops.
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  • The study focuses on understanding the genetic factors behind plant vigor, particularly in rice, and highlights the complexity of mapping this trait due to many genes with small effects and their interactions.
  • Researchers performed a long-read genomic assembly of a tropical japonica rice variety, Carolina Gold, to identify significant structural mutations and understand how these changes affect crop performance.
  • The findings indicate a history of tandem duplications and transposable element activity that contributed to genomic size variations, with structural mutations affecting gene exons being selected against in rice breeding programs over the last century.
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Efforts in genome sequencing in the genus have led to the development of quality reference genomes for several important species including , , and However, less progress has been made for As part of the effort of the USDA-ARS Annual Aflatoxin Workshop Fungal Genome Project, the isolate NRRL3357 was sequenced and resulted in a scaffold-level genome released in 2005. Our goal has been biologically driven, focusing on two areas: isolate variation in aflatoxin production and drought stress exacerbating aflatoxin production by Therefore, we developed two reference pseudomolecule genome assemblies derived from chromosome arms for two isolates: AF13, a MAT1-2, highly stress tolerant, and highly aflatoxigenic isolate; and NRRL3357, a MAT1-1, less stress tolerant, and moderate aflatoxin producer in comparison to AF13. Here, we report these two reference-grade assemblies for these isolates through a combination of PacBio long-read sequencing and optical mapping, and coupled them with comparative, functional, and phylogenetic analyses.

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Like many other crops, the cultivated peanut (Arachis hypogaea L.) is of hybrid origin and has a polyploid genome that contains essentially complete sets of chromosomes from two ancestral species. Here we report the genome sequence of peanut and show that after its polyploid origin, the genome has evolved through mobile-element activity, deletions and by the flow of genetic information between corresponding ancestral chromosomes (that is, homeologous recombination).

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Single nucleotide polymorphisms (SNPs) have many advantages as molecular markers since they are ubiquitous and codominant. However, the discovery of true SNPs in polyploid species is difficult. Peanut ( L.

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Quantitative genetic simulations can save time and resources by optimizing the logistics of an experiment. Current tools are difficult to use by those unfamiliar with programming, and these tools rarely address the actual genetic structure of the population under study. Here, we introduce crossword, which utilizes the widely available re-sequencing and genomics data to create more realistic simulations and to reduce user burden.

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Accurate identification of polymorphisms from sequence data is crucial to unlocking the potential of high throughput sequencing for genomics. Single nucleotide polymorphisms (SNPs) are difficult to accurately identify in polyploid crops due to the duplicative nature of polyploid genomes leading to low confidence in the true alignment of short reads. Implementing a haplotype-based method in contrasting subgenome-specific sequences leads to higher accuracy of SNP identification in polyploids.

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Postharvest aflatoxin contamination is a challenging issue that affects peanut quality. Aflatoxin is produced by fungi belonging to the Aspergilli group, and is known as an acutely toxic, carcinogenic, and immune-suppressing class of mycotoxins. Evidence for several host genetic factors that may impact aflatoxin contamination has been reported, , genes for lipoxygenase (PnLOX1 and PnLOX2/PnLOX3 that showed either positive or negative regulation with infection), reactive oxygen species, and WRKY (highly associated with or differentially expressed upon infection of maize with ); however, their roles remain unclear.

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Aflatoxin contamination is a major economic and food safety concern for the peanut industry that largely could be mitigated by genetic resistance. To screen peanut for aflatoxin resistance, ten genotypes were infected with a green fluorescent protein (GFP)-expressing strain. Percentages of fungal infected area and fungal GFP signal intensity were documented by visual ratings every 8 h for 72 h after inoculation.

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