A Review on Genetic Mechanisms of Plant-pathogen Resistance in Crop Breeding
S. Pandarinathan *
ICAR- Krishi Vigyan Kendra, Virinjipuram, Vellore District- 632 104, Tamil Nadu, India.
Prem Kumar Adhimoolam
Department of Plant Breeding and Genetics, Pandit Jawaharlal Nehru College of Agriculture and Research Institute, Karaikal 609603, Puducherry (U.T), India.
Narayan Pandit Gurav
Department of Plant Pathology, Shri Vaishnav Institute of Agriculture, Shri Vaishnav Vidyapeeth Vishwavidyalay, Indore, Madhya Pradesh, India.
S. G. Shamkuwar
Department of Genetics and Plant Breeding, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
Chandan Kumar Panigrahi
Department of Entomology, Faculty of Agricultural Sciences, Siksha 'O' Anusandhan, Deemed to be University, Bhubaneswar - 751003, Odisha, India.
Sharanabasav Huded
Indian Institute of Rice Research, Hyderabad-500030, Telangana, India.
Manoj Kumar
IARI Regional Station Shimla, 171004, Himanchal Pradesh, India.
*Author to whom correspondence should be addressed.
Abstract
Plant-pathogen resistance is a critical component of sustainable agriculture, essential for protecting crops from devastating diseases and ensuring global food security. This review explores the genetic mechanisms underlying plant-pathogen resistance, focusing on advances in breeding strategies and genetic engineering. Resistance (R) genes, the cornerstone of plant immunity, are categorized by their structural features, including nucleotide-binding site-leucine-rich repeat (NBS-LRR) domains, and function through pathways such as Effector-Triggered Immunity (ETI). The salicylic acid (SA) pathway, crucial for Systemic Acquired Resistance (SAR), and the jasmonic acid (JA) and ethylene (ET) pathways, which drive Induced Systemic Resistance (ISR), are pivotal in orchestrating plant defense responses. Emerging molecular tools like CRISPR-Cas9 enable precise gene editing to enhance R gene function and target susceptibility (S) genes, offering novel pathways to engineer durable resistance. Transgenic approaches, including the introduction of novel R genes and the expression of antimicrobial proteins, have expanded the genetic toolkit for combating pathogens. RNA interference (RNAi) technology further allows for the silencing of critical pathogen genes, adding a layer of defense. Traditional breeding methods, such as hybridization and backcrossing, remain integral, particularly when combined with Marker-Assisted Selection (MAS) and Genomic Selection (GS). MAS facilitates the efficient incorporation of resistance traits using molecular markers, while GS leverages genome-wide data to predict resistance, significantly enhancing breeding efficiency. Challenges such as the rapid evolution of pathogens, resistance breakdown, and climate change-induced shifts in disease dynamics pose significant threats. These challenges necessitate an integrated approach, combining genetic and genomic tools with sustainable disease management practices, such as the use of beneficial microorganisms, precision agriculture, and diversified cropping systems. Future research must focus on understanding the molecular basis of resistance durability, improving predictive models for resistance traits, and developing climate-resilient crop varieties. This integrated strategy is crucial for mitigating disease impact, enhancing crop resilience, and ensuring sustainable agricultural productivity in the face of environmental and biological challenges.
Keywords: Plant-pathogen resistance, genetic engineering, crispr-cas9, RNA interference, resistance genes