Fine mapping a QTL for BYDV-PAV resistance in maize

Area of Science:

• Plant Pathology
• Genetics
• Molecular Biology

Background:

• Barley yellow dwarf (BYD) is a significant cereal virus disease causing substantial yield losses globally.
• Developing genetically resistant cultivars is crucial for economical and eco-friendly BYD control.

Purpose of the Study:

• Identify the gene responsible for BYDV-PAV resistance in maize.
• Investigate genetic variations influencing maize susceptibility to BYDV-PAV.
• Analyze BYDV-PAV infection's impact on gene expression in maize inbreds with varying resistance levels.

Main Methods:

• Utilized two biparental mapping populations to narrow down the quantitative trait locus (QTL) for BYDV-PAV resistance.
• Employed association mapping and gene expression analysis to pinpoint candidate resistance genes.
• Sequenced candidate genes to identify single nucleotide polymorphisms (SNPs) and structural variations.

Main Results:

• Reduced the BYDV-PAV resistance QTL to a 0.3 Mbp region containing nine genes.
• Identified Zm00001eb428010 and Zm00001eb428020 as key candidate genes for BYDV-PAV resistance.
• Found a 54 bp deletion in the 5'-UTR and a protein-altering variant in Zm00001eb428010 in resistant maize inbreds.

Conclusions:

• Zm00001eb428010 and Zm00001eb428020 are strongly implicated in conferring BYDV-PAV resistance.
• Altered protein abundance or properties due to variations in Zm00001eb428010 likely mediate resistance.
• These genes may confer resistance by interfering with virus replication or inducing ROS signaling pathways.