Molecular and Genomic Approaches for Disease Resistance in Crop Plants under Biotic Stress

Abstract

Crop plants are continuously challenged by a wide range of biotic stresses, including pathogens such as bacteria, fungi, viruses, nematodes, and insect pests, which significantly reduce agricultural productivity and threaten global food security. Recent advances in molecular biology and genomics have revolutionized the understanding of plant–pathogen interactions and enabled the development of resistant crop varieties. This review highlights key molecular and genomic approaches employed to enhance disease resistance in crops. These include the identification and functional characterization of resistance (R) genes, quantitative trait loci (QTL) mapping, genome-wide association studies (GWAS), and transcriptomic analyses to unravel defense-related pathways. Furthermore, modern genome-editing tools such as CRISPR/Cas systems, RNA interference (RNAi), and marker-assisted selection (MAS) have accelerated the breeding of disease-resistant cultivars with improved precision and efficiency. The integration of omics technologies—genomics, transcriptomics, proteomics, and metabolomics—provides a comprehensive framework for understanding complex defense mechanisms and host immunity. Despite significant progress, challenges such as pathogen evolution, off-target effects in gene editing, and regulatory constraints remain critical considerations. This study underscores the importance of combining traditional breeding with advanced genomic tools to achieve durable and broad-spectrum resistance in crop plants under biotic stress conditions.