Vigor, vitality and seed dormancy of <em>Avena sativa</em> cultivars in a long-term experiment

Abstract

Vigor, vitality and seed dormancy of 14 Finnish cultivars of Avena sativa in room temperature were studied in a 22-year laboratory experiment. These parameters were studied by measuring morphological and physical characteristics of seeds and by basic germination and enzymatic tests 1, 4, 6, 11, 16, 21 and 22 years after seed harvesting in 1989. Methylene blue, Congo red and 2,3,5-triphenyltetrazolium chloride (TZ) tests were used to estimate seed quality and changes in vitality over time. Seed vitality clearly decreased in all cultivars during the experiment. The mean vitality declined from 96.3% (one year after harvest) to zero at the end. Vitality according to the TZ test was higher than indicated by the basic germination test. The mean vitality loss was 4.6% per year, but there were clear differences between cultivars. The decrease in vitality correlated with loss in seed weight. Clear signs of deepening dormancy were observed. Seed age is an important factor infl uencing vitality and dormancy. Vitality loss of seeds led to deep dormancy. The appearance, water uptake and imbibition of the seeds remained normal until the end. Ageing, vitality loss and dormancy are concluded to be expressions of genes. It is possible that in the future electronic simulation methods will be developed that will enable accurate estimation of oat seed quality without laboratory tests.