qRT-PCR-based Expression Profiling of Selected Drought-Responsive Genes in Chickpea (Cicer arietinum L.) Genotypes under Moisture Stress
Aishwarya Patil
Department of Biotechnology, College of Agriculture, Vijayapur, UAS Dharwad-580 005, India.
Malagouda D. Patil *
Department of Biotechnology, College of Agriculture, Vijayapur, UAS Dharwad-580 005, India and AICRP on MULLaRP, MARS, UAS Dharwad-580 005, India.
Amruta P. Barigal
Department of Plant Pathology, College of Agriculture, UAS Dharwad-580 005, India.
A. G. Vijaykumar
AICRP on Seed (Crops), Seed Unit, University of Agricultural Sciences, Dharwad-580 005, India.
L. M. B. Ashwini
Department of Genetics and Plant Breeding, College of Agriculture, UAS Dharwad 580 005, India.
I. S. Katageri
Department of Biotechnology, College of Agriculture, Vijayapur, UAS Dharwad-580 005, India.
Kumari Basamma
AICRP on Seed (Crops), Seed Unit, University of Agricultural Sciences, Dharwad-580 005, India.
B. H. Prasannakumara
AICRP on MULLaRP, MARS, UAS Dharwad-580 005, India.
A. Guruprasad
Department of Biotechnology, College of Agriculture, Vijayapur, UAS Dharwad-580 005, India.
Iramma Goudar
AICRP on MULLaRP, MARS, UAS Dharwad-580 005, India.
*Author to whom correspondence should be addressed.
Abstract
Background: Gene expression studies have gained prominence as they enable the identification of key regulatory genes and pathways involved in stress response and adaptation. Quantitative Real-Time PCR (qPCR) has emerged as a widely accepted and reliable technique for gene expression analysis due to its high sensitivity, specificity and reproducibility.
Aims: The study aims to evaluate the expression patterns of selected drought-responsive genes in chickpea (Cicer arietinum L.) genotypes under well-watered, moisture stress conditions, and to identify candidate genes associated with drought tolerance.
Study design: Experimental study using a randomised complete block design.
Place and Duration of Study: The study was conducted at the Regional Agricultural Research Station, Vijaypur, during the cropping season of Rabi 2018.
Methodology: Eight chickpea genotypes, including MAGIC lines, were evaluated under well-watered and moisture stress conditions. Total RNA was extracted from plant samples and converted into cDNA. Gene expression analysis was performed using quantitative real-time PCR (qPCR) for selected drought-responsive genes, including DREB, AMADH and DHN. The relative expression levels were calculated using the 2^−ΔΔCt method, with Actin being used as the reference gene for normalization. All reactions were carried out with appropriate technical replicates and expression patterns were analyzed across treatments and genotypes.
Results: The gene expression analysis revealed relatively stable expression patterns across most genotypes under both conditions. However, genes such as DREB, AMADH and DHN showed comparatively higher expression under moisture stress in certain MAGIC genotypes. The reference gene Actin exhibited consistent expression across all samples, confirming its suitability for normalization. Although no significant fold changes were observed, minor variations in gene expression indicated coordinated transcriptional responses to drought stress among the evaluated genotypes.
Conclusion: The results suggest that drought tolerance in chickpea is governed by subtle and coordinated regulation of multiple genes rather than large expression shifts. DREB, CAP2, AMADH, and DHN showed relative expression trends under drought stress; however, these genes should be considered as potential candidates requiring further validation.
Keywords: Chickpea, drought stress, gene expression, MAGIC population, relative expression, actin normalization.