Afek, U.
Orenstein, J.
Nuriel, E., Dept. of Postharvest Science of Fresh Produce, ARO, Gilat Experiment Station, M.P. Negev 2, 85280, Israel

The predominant sweet potato [Ipomoea batatas (L.) Lam] variety grown in Israel, 'Georgia Jet', is hard to store for longer than 1 month because of its low dry matter content (16%). Curing processing is a common pre-storage treatment for sweet potatoes to prevent decay. Although an effective disease preventative in other varieties, it was not effective with Georgia Jet. In experiments conducted during 1995-97 it was proven possible to store var. Georgia Jet for 5 months by means of disinfecting the roots with iprodione in conjunction with the curing procedure. At the end of the storage period, 14% of the roots had decayed following this combined treatment (Exp. 1): 9% suffered soft decay and had to be discarded, and 5% had dry decay, which left them suitable for the local market. Compared with these figures, decay levels following single treatments were 61% with curing, 60% with iprodione and 100% in the control group. Three methods of iprodione application were also tested (Exp. 2): dipping, spraying, and 'Tabor' Atomizing System fogging which produces an extremely fine mist (droplet size < 10 μ). The fogging method proved to be the most effective, with 4% dry decay and 6% soft decay after 5 months of storage.