Incidence and etiology of postharvest fungal diseases of pomegranate (<em>Punica granatum</em> cv. Mollar de Elche) in Spain

Abstract

Spain is the largest European Union producer and exporter of pomegranates. More than 85% of Spanish commercial plantings are located in the Elche area (Alicante Province, SE Spain), where cv. Mollar de Elche is the most important cultivar. The incidence and etiology of postharvest pomegranate diseases were determined in local environmental conditions. Commercially-grown pomegranates cv. Mollar de Elche from two orchards were assessed, during two consecutive seasons, for latent and wound pathogens causing postharvest diseases. Healthy pomegranates were either artificially wounded in the rind or surface disinfected and placed in humid chambers at 20ºC for up to 15 weeks. Additionally, decay was periodically assessed on commercially-handled pomegranates stored at 5ºC for up to 27 weeks. The main causal agents of wound and latent infections were Penicillium spp. and Botrytis cinerea, respectively. The same pathogens were also the most frequently isolated from cold-stored fruit, but decay at 5ºC was only significant after 19 weeks. Another relatively frequent pathogen on fruit incubated at 20ºC was Aspergillus niger. Among the fungi isolated, Penicillium expansum, P. sclerotiorum, P. glabrum and Pilidiella granati were pathogenic on inoculated pomegranates, whereas P. minioluteum and Cytospora annulata were not. No decay caused by Alternaria spp. or Colletotrichum gloeosporioides was observed.