LIBRO-CONGRESO-CITRUS

S09
S09P35
Curative and protective control of Penicillium digitatum following imazalil application in aqueous
dip and wax coating
Njombolwana N.S., Erasmus A., and Fourie P.H.
Stellenbosch University, Citrus Research International (US, CRI), Plant Pathology, South Africa. shellie@sun.ac.za
Imazalil (IMZ) is widely used in citrus packhouses to manage Green Mould, caused by Penicillium digitatum.
The aim of this study was to investigate curative and protective green mould control by IMZ when applied
in a postharvest wax coating, and double IMZ application in aqueous dip followed by coating. Trials were
conducted on clementine, satsuma, ‘Navel’ and ‘Valencia’ sweet orange fruit and treatments were dip only
(IMZ sulphate at 500 µg/mL for 45 s and 90 s), wax coating only (imazalil at 3,000 µg/mL at 1.8 L wax/ton),
and a double application comprising of dip (45 s in IMZ sulphate at 500 µg/mL) followed by 2,000 µg/mL
IMZ in wax coating at 0.6, 1.2 and 1.8 L wax/ton. Double application generally improved IMZ residue loading,
more so with increasing coating load, while the wax coating only resulted in the highest residue level. Poor
curative and protective control of the resistant isolate was observed (