EFFECTS OF WOOD DISTILLATE CONCENTRATIONS ON WHEAT (Triticum durum Desf.) SEED GERMINATION AND DEVELOPMENT UNDER SALINITY STRESS: A PRELIMINARY PETRI DISH TEST

Salinity is increasingly found in the Mediterranean areas due to climate change and excessive mineral fertilization practices. Salt accumulation in soils negatively affects the yield of crops, such as durum wheat (Triticum durum Desf.). Innovative technologies must therefore be developed to protect plants. Wood distillate (WD) is a by-product of pyrolysis that might have a plant biostimulant behaviour. In this study, a preliminary Petri dish test was performed to verify the action of WD as a biostimulant in combination with different levels of salinity. The trial consisted of 5 WD concentrations: control (H2O), diluted 1:10 (D10), 1:100 (D100), 1:500 (D500) and 1:1000 (D1000). Wheat seeds were kept for two hours under the different concentrations of WD then placed in the Petri dishes. At the beginning of the trial, three salinity levels of water [no stress (0 mM), moderate (40 mM) and high (80 mM)] were applied to seeds. The Petri dishes were kept at 23°C for 9 days. All WD concentrations were replicated six times (12 seeds/Petri dish) and, in total, there were 90 Petri dishes. The germination rate of seeds was determined at 2, 5, 7 and 9 days after WD application. Measurements of radicle length (RL), number (RN) and seeds weight (SW) were determined at the end of the trial. For the three salinity levels, seeds under the D10 concentration showed the lowest germination rate during the whole period of the trial. Furthermore, under 80 mM and D10 concentration, seeds showed the lowest germination rate, compared to the other two levels of salinity. Seeds under D1000 and D500 concentrations showed similar RLs as the salinity levels increased (40 and 80 mM). Also, a significantly low RN was registered for the highest salinity level and the D10 dilution. No significant differences were observed for SW.