Resistance gene analogs for yellow mosaic virus resistance in horse gram

Overview

This research initiative focuses on developing genetic resistance to horse gram yellow mosaic virus (HgYMV), a significant disease affecting horse gram, an underutilized legume crop. The project aims to isolate and characterize resistance gene analogs (RGAs) from horse gram genotypes that show natural resistance to HgYMV. By leveraging the conserved sequence similarity among resistance (R) genes across diverse crop species, the work seeks to establish molecular markers that can reliably indicate disease resistance, enabling more efficient breeding programs.

Technical specifications

Research approach:

• Identification of two stable HgYMV-resistant horse gram sources through field-screening in natural disease hot spots and artificial inoculation protocols
• PCR amplification of RGAs from resistant and susceptible genotypes using degenerate primers designed from conserved motifs of functionally validated R-genes
• Translation of RGA nucleotide sequences into amino acid sequences using the ExPASy tool
• Prediction of conserved domains and motifs using the RGAugury bioinformatics tool
• Quantification of sequence similarity with model legume Medicago truncatula using BLASTp algorithm
• Standardized protocol for RGA isolation and characterization already established in mung bean, a comparable legume

Key scientific basis:

• R-gene proteins across distantly related crop species share remarkable sequence similarity and conserved functional domains
• RGAs serve as valuable molecular marker resources as reliable surrogates for HgYMV disease resistance

Technology readiness level

This research is at an early discovery stage. The team has completed preliminary work including identification of resistance sources and standardization of RGA isolation protocols in a related legume (mung bean). Future validation will involve PCR amplification of HgYMV disease RGAs from two resistant and two susceptible horse gram genotypes, followed by bioinformatic characterization of conserved domains and comparative analysis with model legume sequences. The project is positioned for collaboration with breeding programs and partners interested in legume disease resistance.