A study of the optimum drying conditions for cabbage seed following selection on the basis of a newly-emerged radicle

A series of experiments were carried out to study the effects of different drying regimes on the survival of newly-germinated (radicle emerged 0·5-1·5 mm through the seed coat) cabbage seeds and to establish a treatment for reducing the moisture content of these germinated seeds. A preliminary surface-drying step proved necessary to avoid seed agglutination during the main drying stage. Of the drying regimes compared both viability and vigour were most effectively maintained in air, conditioned to between 20 and 30°C and with 80% r.h., flowing through the seeds at 0·25 m s^-1. Under these conditions, the viability and vigour of newly-germinated seed was maintained during drying to an equilibrium moisture content of c. 14%. At this moisture content further radicle growth was prevented and seeds remained free-flowing and separate for sowing or for further treatment.