Abstract

This study aimed to determine the effect of drying conditions and storage time on crambe seed quality. Crambe fruits with a moisture content of 27.0 ± 1.0% (wet basis; w.b.) were used. These fruits were dried in a forced-air oven and were kept under controlled temperatures of 35, 45, 60, 75 and 90°C at relative humidities of 20.9, 8.7, 6.8, 4.8 and 2.3%, respectively. During the drying process, trays containing 0.4 kg of fruit were periodically weighed until the final drying point of 7.0 ± 1.3% (w.b.). The fruits were packed in glass jars covered with permeable fabric. Each container had 400 g of fruit, and the containers were kept under ambient conditions (temperature of 26 ± 3°C and relative humidity of 55 ± 12%). The temperature and relative humidity of the environment were recorded by a digital datalogger. The samples were evaluated at 0, 3, 6, 9 and 12 months for moisture content, electrical conductivity (EC), germination percentage and germination speed index (GSI). Drying the crambe fruit at high temperatures caused a decrease in the physiological quality of the seeds. There was an increase in the amount of electrolytes released by the seeds over time. Seeds stored for 12 months at room temperature had superior germination regardless of drying temperature.

Key words: Physiological quality, Crambe abyssinica, biodiesel.