Seed germination percentage and chromosomal aberration in root tip cells of 20 wheat accessions were tested in this study. The results showed that chromosomal aberration rate of seeds with lower germination percentage stored in mid term genebank was obviously higher than that of those with higher germination percentage stored in long term genebank of the same variety.Seed chromosomal aberration ratio in root tip cells was significantly and negatively correlated with germination percentage, but no significant association with storage time when seeds stored in the mid term and long term genebanks as a whole.Seed chromosomal aberration ratio in root tip cells was significantly associated with germination percentage and storage time for seeds neither stored in the mid term genebank nor long term genebank, respectively. According to the variations in the hordein spectrum, four biotypes may be recognized in the barley landrace cv. Punaiganmu. Biotype ratio varied with decline of germination percentage. One biotype disappeared while the ratio of another one increased from 83% to 95% when seed germination percentage declined from 95% to 34%. The result indicated that the loss of seed viability and differential survival of the biotypes resulted in selection and genetic shifts in germplasm accessions.