Influence of KCl salt on the germination and early seedling characteristics of Aegilops biuncialis Vis.

The aim of the study was to determine the effect of KCl salinity stress on germination characteristics and early seedling growth of 5 populations of Aegilops biuncialis Vis. maintained in the ex situ collection of the National Genebank of Bulgaria. Six different concentrations of KCl (50, 100, 150, 200, 250 and 300 mM) were used as treatments and deionised water as control. To determine the salinity tolerance, the following germination characteristics were studied: germination percentage (%), germination velocity coefficient, germination rate index (% day-1) and mean germination time (day). Shoot and root length (cm), shoot and root fresh weight (mg plant-1) and shoot and root dry weight (mg plant-1) were measured eight days after germination. Relative injury coefficient, root and shoot height reduction and salinity tolerance index were also calculated. The results showed that salinity prolonged the mean germination time and significantly decreased the studied germination and seedling growth characteristics with increasing concentration of KCl. The inhibitory effect of increasing KCl concentrations was stronger on root height reduction compared to shoot height reduction in all populations studied except the population of BGR44617. The highest relative injury coefficient was recorded for BGR44617, BGR44900 and BGR43660 when treated with 300 mM KCl solution, respectively, these accessions were classified as susceptible for germination and seedling growth. BGR43667 was relatively the most tolerant to salinisation with KCl at the seedling growth stage.