Combination of Irradiation and Sodium Carbonate to Control Postharvest Penicillium Decay of Apples

Penicillium expansum is an important pathogen causing considerable postharvest losses in apples. Due to some restrictions applied for chemicals, there is a need for new approaches and combined treatments for inhibition of fungi. In present study, O2 isolate of P. expansum, isolated from apples in cold storages of Kayseri, was used. Inoculated apples were irradiated with 3.0, 3.5 and 4.0 kGy and stored at 3-4ºC for 40 days. While the lesion diameter of untreated apples at 40th day was 20.28 mm, the apples treated with 3.5 kGy had a diameter of 7.85 mm. Differences in lession diamaters were found to be significant (p<0.05).In second part of study, inoculated apples were treated with sodium carbonate (SC,%3)+2.5 kGy, SC+3.0 kGy and SC+3.5 kGy combinations and stored at 3-4ºC for 40 days. At the 40th day, lesion diameters were measured as 49.00 mm and 19.18 mm for control samples and SC+3.0 kGy treatment, respectively. The area under the disease progress curve (AUDPC) was evaluated to calculate individual and total AUDPC.Long-term impacts of treatments on P.expansum were also evaluated by performing re-isolation from untreated and SC+3.0 kGy treatments. There were no significant diffrerences between control and treated ones with regard tocultural characteristics and pathogenicity of fungus.