Evaluation of the efficacy of fungicide fludioxonil in the postharvest control of bull's eye rot (Neofabraea alba) in Chile

M. Lolas, G. Díaz, R. Mendez, M. Cáceres, L. Neubauer
Bull's eye rot, caused by Neofabraea alba, is a serious disease affecting apples, causing annual losses to the Chilean apple industry during postharvest. The effectiveness of fungicide fludioxonil (Starter Pro 230 SC, ANASAC Chile S.A.; and Scholar 230 SC, Syngenta) in the control of “bull's eye” rot in 'Cripps Pink' apples was determined by applications via drenching after harvest. Apples used in this study were obtained from a commercial orchard, located in Longaví, Chile, which historically presented a high pressure of bull's eye rot. Treatments, which were applied using an experimental drencher with a recirculating system, consisted in 100 L of fungicide solution showering 6 boxes of 80 apples for 30 s. Then, boxes were removed; air dried and stored at 0°C for 75 and 120 days in a completely randomised design. At each period of storage, the boxes were kept at 22°C for 7 days (shelf-life period), after each apple being evaluated for the presence of rot lesions. Finally, after shelf-life period, the incidence of rot lesions in each box was assessed. Treatments consisted in Starter Pro 230 SC at 200 and 100 mL hL-1; Scholar 230 SC at 200 mL hL-1 and, Starter Pro 230 SC at 100 mL hL-1 + Tecto 500 SC (thiabendazole) at 125 mL hL-1. Only water was used as a control treatment, in which the incidence of 'bull's eye' rot reached 42.9% in those apples, cold stored for 120 days + 7 days at 22°C. Starter Pro 230 SC and Scholar 230 SC at doses of 200 mL hL-1, significantly reduced bull's eye rots incidence in apples evaluated after 120 days of storage at 0°C and also, after 7 days at 22°C. However, at doses of 100 mL hL-1, Starter Pro 230 SC was not effective compared with the control. The mixture of Starter Pro 230 SC at dose of 100 mL hL-1 and Tecto 500 SC at dose of 125 mL hL-1 was significantly effective in reducing the bull's eye rot incidence.
Lolas, M., Díaz, G., Mendez, R., Cáceres, M. and Neubauer, L. (2016). Evaluation of the efficacy of fungicide fludioxonil in the postharvest control of bull's eye rot (Neofabraea alba) in Chile. Acta Hortic. 1144, 461-464
DOI: 10.17660/ActaHortic.2016.1144.68
Malus × domestica, Neofabraea, chemical control, drenching, phenyl-pyrrol, lenticel rot, Phlyctema

Acta Horticulturae