A controlled deterioration test for Arabidopsis thaliana reveals genetic variation in seed quality

Several ecotypes (Landsberg erecta, Enkheim, Cape Verde islands and C24) and mutants (abal-1, abi3-7, gal-1 and tt4-1) of Arabidopsis thaliana L. were subjected to a variety of seed quality tests to assess genetic variation. The wild type (Landsberg erecta) and two mutants (abi3-7, tt4-1) gave close to 100% germination at 25°C whilst other genotypes and mutants showed varying degrees of dormancy. A controlled deterioration assay was developed to compare genotypes with regard to their storability. Equilibration of the seeds at 85% relative humidity and subsequent hermetic storage at 40°C was more discriminatory in identifying differences in storability than was equilibration at 75% relative humidity followed by storage at 40 or 50°C. With longer deterioration treatments, germination was reduced and average germination time and frequency of abnormal seedlings increased. This test revealed clear differences in seed stress tolerance amongst genotypes. Additional differences in seed quality were observed in germination tests performed at sub-optimal conditions, such as low temperatures (10 and 15°C) or under osmotic stress (-0.25 MPa and -0.50 MPa). The observed differences in seed quality and the assays developed can be used to identify genes involved in different aspects of seed quality.