Germination was similar for seeds stored for 371 days at 5°C either with or without the beads after the
same initial drying treatment. There was lower germination of seeds dried at low temperature and then stored
at -20°C; however, this was attributed to dormancy.Whilst the water uptake isotherms confirmed the high
capacity of the beads compared with silica gel, particularly at low relative humidity, the beads do not work to
full capacity in a bead-seed system and the adsorption properties appeared to change. Further work is required
to optimise the use of these beads for drying seeds to target moisture contents, without either under-drying
which could lead to undesirable high rates of viability loss, or unnecessary and perhaps detrimental over-drying.
Introduction
In contrast to the bulk drying of large volumes of seed carried out by commercial seed
and grain companies, genebanks often dry relatively small volumes of seed. It may be
necessary to dry many different samples at any one time, but it is vital that the seeds from
different accessions (i.e., plants or plots) be kept separate. It is also important that the
quality of the seeds is not compromised, since this will reduce the longevity of the seeds
in genebank storage.
The 1994 FAO/IPGRI Genebank Standards recommend drying seed germplasm as
soon as