Effects of hydro and osmopriming on drought stress tolerance during germination in four grass species

Abstract

The objectives of this study were to evaluate effects of hydropriming and osmopriming techniques on improvement of the germination characteristics of four grass species under simulated drought stress by PEG. Germination in primed and non-primed seeds was delayed through drought stress. Then the increased osmotic potential measurements for, percentage of seeds that germinated, germination rate, seedling length and seedling dry weight were shown to decrease in all of the investigated species. Seeds were able to germinate in 0, −0.4 and −0.8 MPa concentrations of PEG and scant seed germination was observed at −1.2 MPa of PEG. It was concluded that inhibited germination was a result of osmotic effect and varied according to the different species tested. Osmopriming, rather than hydropriming treatment increased germination parameters under drought stress. For its ability to withstand drought conditions, it was observed that the grass species Agropyron elongatum had better responses than the other species to both priming treatments on conditions for germination especially at lower osmotic potentials (-1.2 MPa).