A remorin gene is implicated in quantitative disease resistance in maize

Area of Science:

• Plant pathology
• Molecular genetics
• Crop science

Background:

• Quantitative disease resistance (QDR) is crucial for developing resilient crop cultivars, yet its underlying mechanisms are not fully understood.
• QDR loci often confer resistance to multiple diseases, making them valuable for breeding programs.
• Identifying genes involved in QDR is essential for enhancing crop protection strategies.

Purpose of the Study:

• To fine-map a quantitative trait locus (QTL) associated with disease resistance in maize.
• To identify and characterize candidate genes within the mapped QTL region, specifically focusing on resistance to northern leaf blight (NLB).
• To elucidate the role of maize remorin (ZmREM6.3) in quantitative disease resistance.

Main Methods:

• High-resolution fine mapping of a known disease resistance QTL on maize chromosome 1.
• Expression analysis of candidate genes in resistant and susceptible maize lines.
• Mutant analysis using transposon tagging to assess the function of ZmREM6.3 and a chaperonin gene in disease resistance.

Main Results:

• A QTL conferring resistance to northern leaf blight (NLB), Stewart's wilt, and common rust was fine-mapped.
• The maize remorin gene, ZmREM6.3, showed higher expression in the resistant maize line and its mutant exhibited increased susceptibility to NLB.
• ZmREM6.3 is strongly implicated as a key component of quantitative disease resistance in maize.

Conclusions:

• This study provides the first evidence for a role of remorins in plant-fungal interactions, specifically in maize resistance to NLB.
• ZmREM6.3 is identified as a significant contributor to quantitative disease resistance in maize.
• The findings open new avenues for understanding and exploiting remorin-mediated resistance in crop improvement.