Accelerated aging time estimation for birdsfoot trefoil seed

Seed Industry perform seed vigour tests as an important component of seed quality control, particularly in species like Lotus corniculatus L. which is characterized by having low seed vigour. The availability of a technique that allows discrimination among seed lots for this quality component is very important. The accelerated aging condition as a criterion for a seed vigour test was investigated in birdsfoot trefoil. Two seed lots from San Gabriel cultivar with similar germination percentages but harvested in 1999 (SG-A) and 1993 (SG-B) were used. Samples of I g seeds were exposed to 41 degrees C and 95% of relative humidity during different periods of aging. Aging times longer than 24 h reduced the seed germination dramatically, whereas an aging time of 18 h presented the highest correlation (0.95**-0.96**) with the soil seedling emergence. The evaluation of this aging time (18 h) in 10 seed lots, allowed confirming its discriminatory power to differentiate the lots for its seed vigour condition and potential planting value. This accelerated aging vigour test (AAVT) was more sensitive than the standard germination test to determine the physiologic quality among seed lots. An aging time of 18 h, a temperature of 41 degrees C, a relative humidity of 95% and seed samples of I g is recommended preliminary in birdsfoot trefoil.