Yellow Dwarf Virus Resistance in Barley: Phenotyping, Remote Imagery, and Virus-Vector Characterization

Area of Science:

• Plant Pathology
• Agronomy
• Genetics

Background:

• Yellow dwarf viruses (YDVs) transmitted by aphids pose significant economic threats to barley (Hordeum vulgare) and other grass crops.
• Effective detection and control strategies are crucial for maintaining crop yield and quality.
• Genetic resistance offers an environmentally and economically sustainable alternative to chemical insecticides.

Purpose of the Study:

• To screen a barley population for YDV resistance under natural field conditions.
• To evaluate the efficacy of drone imagery as a tool for assessing plant disease resistance.
• To identify genomic regions associated with YDV resistance through genome-wide association studies.

Main Methods:

• Phenotypic assessment of YDV disease symptoms in 192 barley inbred lines.
• Drone-based aerial imaging for disease severity estimation and correlation with ground data.
• Identification of prevalent YDV and aphid vector species.
• Genome-wide association study (GWAS) to map quantitative trait loci (QTLs).

Main Results:

• Significant genetic variation in YDV symptom severity was observed, correlating with grain yield.
• Drone-based YDV severity estimates showed high correlation (r=0.65) with ground-based assessments.
• Three aphid species and three YDV species were identified; no genotypic influence on vector distribution was found.
• A QTL for YDV resistance was detected on chromosome 2H, but not via drone imaging.
• QTLs for canopy cover and normalized difference vegetation index were successfully mapped using drone data.

Conclusions:

• Drone imagery is a valuable tool for assessing YDV resistance in barley breeding programs.
• Genetic resistance to YDVs can be effectively mapped using GWAS.
• This study provides a framework for integrating drone technology into resistance breeding for cereal and grass viruses.