Transcriptome profiling reveals insight into the cold response of perennial ryegrass genotypes with contrasting cold tolerance

Knowledge about molecular mechanisms underlying cold and freezing stress responses in perennial ryegrass is scarce. The current study aims to study cold and freezing stress responses of perennial ryegrass genotypes with contrasting cold tolerances. A panel of 160 genotypes were screened for cold tolerances based on electrolyte leakage % measured after 24 hrs at 12 °C and 24 hrs at 14 °C. Among them, 4 genotypes (2 low EL% and 2 high EL%) were selected to study cold and freezing stress responses. Plants were sampled at 6 timepoints; control (T1), beginning of cold acclimation (T2), 2 weeks into cold acclimation (T3), end of cold cold acclimation (T4), -5°C (T5), -10 °C (T6) followed by RNA extraction and sequencing.