POSTHARVEST APPLICATION OF THE YEAST CRYPTOCOCCUS LAURENTII REDUCES APPLE ROTS

Abstract

Rots might be responsible for substantial post-harvest losses on apples (Malus domestica). The blue mold caused by Penicillium expansum, the bitter rot caused by Glomerella cingulata and the 'bull's-eye rot' induced by Pezicula malicorticis are among the most common rots. Great attention has been given to less environmental damaging alternatives for the control of post-harvest diseases. The post-harvest application of yeasts, such as Cryptococcus laurentii, is one of the options to control fruit rots. This study was carried out to test the efficiency of C. laurentii on fruit rots control in 'Fuji' and 'Gala' apples. After application of treatments by immersion, the fruits were stored in laboratory (15-20°C and 60-70% RH) or in cold storage (1°C and 90-95% RH). The pathogens were applied at the concentration of 10 2 conidia mL -1 , the yeast at 10 7 cells mL -1 and the fungicides at 150 mg l -1 . An isolate (36) of C. laurentii was as efficient as the fungicides (thiabendazole and iprodione) to reduce apple fruit rots (G. cingulata, P. expansum, and P. malicorticis). In cold storage trials, C. laurentii was as efficient as the fungicides (thiabendazole, iprodione, chlorhexidine digluconate, sodium dichloro-s-triazinetrione, sodium dicloroisocyanurate and sodium hypochlorite) to reduce P. expansum fruit rot. The application of C. laurentii did not affect flesh firmness and total soluble solids content of the fruits.