Storage of pre-germinated vegetable seeds

Results showed that viability of pre-germinated cucumber seed was excellent for up to 10 days, tomato, cabbage and lettuce for up to five days, suspended in all media packed either in glass bottles or aluminum laminated bags stored both at 5 deg C and 10 deg C temperatures. Storage of pre-germinated onion seed under these conditions was not acceptable. If pre-germinated seeds were stored longer, there was a reduction in seedling emergence ranging from 32 to 70% and seedlings tended to produce radicles longer than five to 13 mm. Radicle elongation is linearly related to storage duration. Radicle elongation was minimal when pre-germinated seeds were stored in gelatin and cornstarch. Rapid radicle elongation was observed under cold air environment. Seeds having longer radicles emerged much earlier and established heavier plants but enhanced the production of abnormal seedlings. A strong correlation was observed between the occurrence of abnormal seedlings and the storage duration. Pre-germinated lettuce and cabbage seeds that were stored in cold air of both temperatures produced cotyledonary leaves after 5 days. These seeds and seeds having long radicles were not suitable for fluid drilling and markedly increased the number of abnormal seedlings. Storage in cornstarch medium markedly reduced seedlings viability after 10 days for all crops at both temperatures and packaging materials. This suggests that the environment of cornstarch medium was more unfavorable to maintain seedling vigor and viability in storage than the other two media used. No single factor alone could affect the extension of the storage life of pre-germinated seeds but storage media and temperature seemed more critical. Plant dry weight had higher correlation with the storage duration at all time periods for all crops. Post storage viability and vigor decreased when the storage duration was longer. Degradation of functional structures, increase of free fatty acid content and enzymic degradation were the suggested reasons for loss of vigor.