Freeze dried onion seeds stored with zeolite desiccants
maintained high germination (75%) after 6 years even at high
temperatures of 40–50 8C (Woodstock and Faul, 1981). It is
advisable to reduce the seed moisture to as low as possible for
example 3–4% SMC prior to onion seed storage with silica gels
in impermeable, compact and closed containers to prevent loss
of seed viability and to ensure high percentage of vigourous
seedlings in succeeding growing seasons, as these moisture
absorbing desiccants stabilize seed moisture during storage and
so, minimize the effects of fluctuating temperature on seed
deterioration (Horky, 1991). In our experiments, onion seeds
were not excessively dried, which is detrimental to the ‘strongly
bound water’. However, the seeds dried in a tray drier were
further desiccated with silica gel, packed in various packaging
materials and stored at ambient and at 25 8C conditions