Monitoring of oil seed viabilityafter 25 years long term storage

摘要

A total of 1,134 seed accessions from 7 plant species (Sesamum indicum L, Helianthus annuus L, Arachis hypogaea L, Glycine max (L.) Merr., Brassica napus L, Linum usitatissimum L and Papaver somniferum L.) stored for 25 years in the National Genebankof Bulgaria are evaluated. All seed accessions are maintained as base collection under long-term storage conditions with low moisture contents (5±2%) in hermetically closed containers at -18°C. On the basis of experimental data, the seed storage characters a (standard deviation of seed death in storage), P50% (the time for viability to fall to 50%) and P10% (the time for viability reduction of 10%) are determined allowing the prediction of seed storage life and the regeneration needs.The results showed significant differences in loss of seed viability among species and within the species. Minimal changes between seed germinations at the beginning of storage and after a significant time of storage in both firstcontrol test (with storage time of 10 years) and second control test (with storage time of 25years) are detected for accessions from Sesamum indicum L and Papaver somniferum L. species. More differences in germinative activity after 10 and 25 years of storage are registered between individual genotypes of Arachis hypogaea L. and Glycine max (L.) Merr.The а values varied from 24.39 years (Arachis hypogaea L.) to 125 years (for Sesamum indicum L and Helianthus annuus L. There are wide variation across species, both in time taken for the viability to fall to 50% and in time taken for the seed viabilityreduction of 10%. The study illustrates the positive effect of both seed storability early monitoring and prediction of regeneration needs as a tool for limiting undesired losses.