Improved drought tolerance of EMS mutagenized Alfalfa (Medicago sativa L.) mutants by in vitro screening at germination stage

Abstract

The objectives of this study were to determine drought tolerant novel mutant of alfalfa (Medicago sativa L.) genotypes by screening EMS mutagenized 340675 M3 seeds at germination stages in the presence of osmotic stress of 35% PEG6000. Root growth assay provided several drought tolerant candidate mutants. Of those, 4 mutants were further evaluated at water deficit conditions applied for 24 days after the first cutting at flowering bud stage. The results revealed that mutants determined as drought tolerant at germination stage were also tolerant to water deficit conditions. Protein content and superoxide dismutase values were found to be higher in all mutants than controls. Ascorbate peroxides, glutton reductase and lipid peroxidase values varied based on the mutant genotype and duration of drought stress. Drought stress significantly changed transcriptional levels of MtP5CS, MtDehyd, MseIF-2, MtRD2 and MsNAC genes. These results indicated that in vitro screening of alfalfa mutant seeds for osmatic tolerance at germination and early seedling growth stages was successfully able to determine the drought tolerant alfalfa mutants which were also tolerant to water deficit conditions after the first cutting at flowering bud stage.

A comparison of procedures for evaluating and selecting alfalfa landrace germplasm for tolerance to salinity

“…Crop Science (Campanelli et al, 2013;Ruta et al, 2022), providing encouraging results under in vitro testing conditions that were not verified under field conditions. In vitro screening of alfalfa seedlings has been proposed also for tolerance to other abiotic stresses, such as soil aluminum (Khu et al, 2012) or drought (Tiryaki et al, 2022). The current, composite investigation encompassed two distinct phases.…”