SUMMARY

Studies were conducted during 8 months in 1993/94 and 1994/95 storage period to investigate the effect of topped and non-topped in ambient air circulated and refrigerated bulk storage system on storage potentials of onion bulbs CV. Akgün-12, Kantartopu-3 and Valencia. Suitable bulk height for long term storage was also observed based on sprouting, decay, total losses and potential sprouting.

Storage losses were more in 1994/95 storage period than in 1993/94 storage period under 6°C-8°C for 3 months + 5°C-7°C for 5 months temperature regime. According to results Valencia varieties is suitable for medium length storage (for 4 or 5 months) and Akgün-12 and Kantartopu-3 varieties are suitable for long time storage (8 months without application of growth regulator). Sprouting, decay, total loss rate and potential sprouting were increased with storage time. In general total storage losses of topped bulbs of all varieties were less than non-topped bulbs but sprouting and decay rates between these bulbs were not different significantly. Bulk height of 2 meter was found to suitable. Bulk storage system was more economic than box storage loses and expenses.