Integrated Approaches for Rapid Screening of Salt-tolerant Chrysanthemum Genotypes

Abstract Ten Chrysanthemum morifolium genotypes were assessed for their responses to different salt concentrations at biochemical, molecular and anatomical dimensions. Biochemical analysis revealed variations in enzyme activities and lipid peroxidation levels, shedding light on salt stress response mechanisms of chrysanthemum. Notably, different degrees of tolerance were observed among the genotypes, with Bidhan Lalima and Bidhan Sabita showing high salt tolerance, while Bidhan Jayanti and Silk Brocate as highly salt susceptible. Molecular analysis indicated higher expression of stress-responsive gene and transcription factors in stress-susceptible genotypes, suggesting predictable variations in stress response mechanisms. Specifically, CmSOD, CmWRKY10, CmNCED3A, CmHSFA4, and CmHSP70 genes played distinct roles in salt mitigation mechanisms in chrysanthemum genotypes. Root anatomical studies revealed genotype-specific root anatomy, indicating distinct root structures in tolerant and susceptible genotypes to cope with salt stress. This study underscores the combined utility of biochemical, molecular, and anatomical approaches for rapid screening of salt-tolerant chrysanthemum genotypes. The score plot distinguished the genotypes under study as highly tolerant, moderately tolerant and susceptible genotypes based on their response to salt stress. Correlation analysis depicted a strong correlation of MDA with chitinase and POD activity in chrysanthemum genotypes under salt stress. These findings provide valuable insights for future breeding programs aimed at developing salt-tolerant chrysanthemum genotypes for sustainable floriculture practices.