Germination as an unreliable indicator of the effectiveness of cryopreservative procedures for imbibed seeds

Abstract

Tomato seeds of 49 per cent moisture content have been thawed from liquid nitrogen (-196 °C) with no loss of germination following both slow (12 °C min-1) and rapid (850 °C min-1) cooling, using 35 per cent dimethyl sulphoxide (DMSO) as a cryoprotectant. Lower concentrations of DMSO resulted in reduced germination. High proportions of seedlings from frozen/thawed seed failed to survive transplanting into soil, especially if they had been cooled rapidly. Seedlings grown to maturity after the slow cooling treatment showed a greater proportion of morphological abnormalities than a control population or those that had been rapidly cooled.It is suggested that if cryopreservative techniques are to be evaluated for the storage of recalcitrant seeds, false impressions of efficacy might be gained by reliance solely on germination testing. © 1985 Annals of Botany Company.