Black rot of pineapple, caused by Chalara paradoxa (De Seyn.) Sacc., is a postharvest disease responsible by high losses on fruits destined to the fresh market and to the processing industry. Penetration of fungus inside cells occurs through wounds and stem cutting, causing infection. The objective of this work was to evaluate the effect of abiotic resistance inducers, chemical fungicide and natural plant extracts on black rot of pineapple control. 32 fruits of pineapple cv pérola were used. They were disinfested with sodium hypochlorite (commercial product) at 4% for 5 minutes. After drying at room temperature, fruits were treated, by spraying, with: 1) Distilled water (control), 2) Derosal 3) Bion® (Acibenzolar-S-methyl); 4) Ecolife®; 5) Agro-Mos®; 6) Allium sativum extract at 20%; 7) A. cepa at 20% and 8) Azadirachta indica at 20%. Treated fruits were incubated on humid chamber with polyethylene bags during 24 hours before inoculation procedure using a mycelia disk added to a wound at the epidermic area of the fruit. Evaluation of disease progress was done by a disease index: 1- no symptoms, 2- black rot on epidermis reaching 1-5 simple fruits, 3- black rot on epidermis reaching 6-10 simple fruits, 4- internal brown yellow rot, 5- black rot and disintegration of internal area in more than 50%. The experimental design was a completely randomized with eight treatments and five replicates, using general linear models with multinomial distribution and the averages were compared by Scott-Knott test at 5%. The best results were found in the Ecolife treatment with longer fruit life span and less severity in the symptoms of the disease.
Ananas comosus var. comosus; Chalara paradoxa; postharvest control
