Effects of dehydration treatments on germination, seedling vigour, and cytoplasmic leakage in wild oats and birdsfoot trefoil
The stage in germination at which birdsfoot trefoil (Lotus corniculatus L. cv. Carroll) seeds and wild oat (Avena fatua L.) embryos became sensitive to dehydration was determined using percent germination, seedling vigour, and cytoplasmic leakage as indicators of cellular damage. Dehydration of seeds or embryos in the early stages of germination did not impair the subsequent germination or vigour of the seedling. In addition, cytoplasmic leakage during rehydration remained low. Dehydration of wild oat embryos grown on a germinating medium for 24 h or of birdsfoot trefoil seeds 18 h after the start of imbibition resulted in decreased germination and vigour and increased cytoplasmic leakage during rehydration. Damage to sensitive birdsfoot trefoil seeds occurred only in samples dehydrated below 20% moisture. The increase in cytoplasmic leakage from damaged seeds presumably reflects a loss in membrane integrity as a result of dehydration which may contribute to the reduced germination and vigour of the seeds.