Physiological and biochemical changes during accelerated ageing of stored wheat seeds

Abstract:

Here is a paradox worth examining: wheat seeds that pass every standard germination test at harvest can still fail catastrophically if stored under sub-optimal conditions for just one season. This research tracked physiological and biochemical deterioration in two Polish winter wheat cultivars (Arkadia and Bamberka) subjected to accelerated ageing (41 °C, 100% RH) for 0, 3, 6, 9, 12, and 15 days at the Silesian Agricultural College, Gliwice, Poland, between September 2022 and June 2024. Germination dropped from 96.4% at day 0 to 22.1% by day 15. Lipid peroxidation, measured as malondialdehyde (MDA) content, increased nearly ninefold (3.2 to 28.6 nmol/g). Antioxidant enzyme activities (superoxide dismutase and catalase) peaked at day 6 before declining sharply, indicating exhaustion of the defence system. Seedling vigour index fell by 85.5%. Membrane integrity, assessed by electrical conductivity of seed leachate, deteriorated in parallel with MDA accumulation (r = 0.94). These results clarify the sequence of biochemical events underlying seed quality loss and identify MDA content as the earliest reliable marker of deterioration in stored wheat.