Estimating crown rot risk in reefer transported banana fruit

Crown rot is caused by a fungal complex affecting banana cultivation worldwide and considered the most damaging postharvest disease. Crown rot can show up in the country of destination after weeks of transport in refrigerated containers (reefers) without being detected before transport. Here, an approach is presented to assess the risk of crown rot in the country of destination based on quality inspection reports of about 20,000 reefer shipments and historical weather data from the country of origin (Peru, Ecuador, Nicaragua, Dominican Republic and Costa Rica). Incidence of crown rot in the country of origin was estimated (backwards in time), taking into account the duration and the mode of reefer transport (Modified air packaging or Controlled atmosphere), using a stochastic model on fungal growth during transit. The crown rot incidence at origin was subsequently linked to historical temperature data via a kinetic fungal growth model during cultivation. This model assumes that the fungal complex is inactive or active. The inactive form can become active and then either be destroyed or grow exponentially, the latter leading to crown rot. Results show that the model simulates crown rot occurrence and intensity over six years, with parameters varying by country, suggesting different fungal complexes. The model describes the crown rot risk in the country of destination countries up to 40 days in advance, even though reefer transport time is typically under 30 days. This approach opens up the possibility to forecast crown rot risk in the country of destination in future shipments.