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Banayad, H.

Publications and source records attributed to Banayad, H..

2 recordsLinked to original sources

Leveraging foundation models to dissect the genetic basis of cluster compactness and yield in grapevine

Grape cluster compactness is a key trait that influence fruit quality, yield, and disease susceptibility. Understanding the genetic basis of this trait is essential for optimizing vineyard management and improving grapevine cultivars. In this study, we performed quantitative trait locus (QTL) mapping to identify genomic regions associated with cluster architecture and yield components in a bi-parental population derived from Vitis vinifera cv. Riesling x Cabernet Sauvignon. A total of 138 full-sibling progeny were evaluated over two growing seasons at Oakville, Napa Valley, California. Traditional yield-related traits were measured, including cluster number, total cluster weight, and average cluster weight. Additionally, an image-based phenotyping pipeline leveraging the foundation model Segment Anything Model (SAM) was employed to segment individual berries, measure their size and shape, and compute cluster compactness with minimal manual intervention. Trait correlations revealed that compact clusters tended to have a higher berry count but smaller berry size, highlighting the role of compactness in modulating cluster structure. Heritability estimates varied across traits, with berry dimensions and compactness displaying moderate to high heritability, indicating strong genetic control. Two parental linkage maps were constructed using a pseudo-test cross strategy. QTL mapping identified multiple loci associated with cluster architecture and yield components, with several stable QTLs detected across both years. Notably, a QTL for cluster compactness was found in both seasons on chromosome 1 in Cabernet Sauvignon. Other stable QTLs were associated with berry size (chromosomes 6 and 17) and berry count (chromosome 5 in Cabernet Sauvignon and chromosome 7 in Riesling). Additional QTLs were detected in a single year, reflecting the influence of environmental variation. Our findings provide valuable insights into the application of foundation models requiring no prior training and minimal intervention for high-quality segmentation and enhance our understanding of the genetic architecture of cluster compactness and yield traits. The genomic regions identified in this study offer promising targets for breeding programs aimed at improving grape quality and disease resistance.

genetics↗

The Genetic Basis of Chloride Exclusion in Grapevines

Mediterranean regions are among the most important areas for global grape production, characterized by dry climates and frequent challenges associated with soil salinity. In these environments, chloride toxicity is a major factor limiting vine growth and fruit quality. Despite the critical role of chloride exclusion in salinity tolerance, the genetic mechanisms underlying this trait remain poorly understood. In this study, we leveraged one of the largest Vitis germplasm collections, comprising 335 accessions from 18 wild and cultivated Vitis species, to characterize natural variation in chloride exclusion. This diverse panel, which includes accessions from the southwestern United States and Mexico, captures a broad range of evolutionary adaptations to abiotic stress, providing an unprecedented opportunity to investigate the genetic basis of salinity tolerance. Using genome-wide association (GWA) and quantitative trait loci (QTL) mapping, we identified a major QTL on chromosome 8 containing candidate genes encoding cation/H exchangers (CHX), which are involved in ion transport and homeostasis. To validate these findings, we analyzed a mapping population derived from V. acerifolia longii 9018 and the commercial rootstock GRN3, confirming the chromosome 8 locus as a major determinant of chloride exclusion. Structural variant analysis revealed key non-synonymous substitutions within CHX genes, suggesting potential functional roles in salinity tolerance. Additionally, we discovered a novel QTL on chromosome 19 enriched with G-type lectin S-receptor-like serine/threonine-protein kinases, known regulators of stress signaling. By integrating extensive phenotypic and genomic data across a diverse Vitis collection, this study provides novel insights into the genetic architecture of chloride exclusion and identifies valuable candidate genes for breeding salt-tolerant rootstocks.

genetics↗