2 5h furanone

The seeds were surface sterilised with 70% ethanol and washed three times with sterile water. Plastic Petri dishes (9 cm) containing filter paper were filled with 15 cm³ of distilled water (for control and 3-h hydroprimed seeds) or butenolide i.e., 2(5H)-furanone) (Sigma-Aldrich, St. Louis, MO, USA) in the following dilutions in distilled water: 10⁻⁶ M, 10⁻⁵ M and 10⁻⁴ M. Seed treatments with the mentioned butenolide concentrations were named But 1, But 2 and But 3, respectively. One hundred fifty seeds of each cultivar were placed in the dishes, fifteen seeds per dish, ten dishes for each combination of cultivar/temperature/treatment. The seeds germinated in dark in phytotronic chambers (phytotron facilities of the Department of Plant Physiology, University of Agriculture in Krakow, Kraków, Poland) at 7 °C (cold) or 13 °C (control). Hydropriming consisted in soaking the seeds in distilled water at 20 °C for 3 h before transfer to the final temperature of 7 °C or 13 °C. This treatment was referenced to as ‘3 h’. The applied butenolide dilutions and duration of hydropriming were chosen based on the preliminary study.