First report of Neofusicoccum luteum causing stem-end rot disease on avocado fruits in Chile.

Abstract

In January 2017, avocado fruits (cv. Hass) showed symptoms of light brown spherical lesions in the peel and pulp, peduncle base lesions (3 to 5 cm width), and necrotic veins. Symptomatic fruits were obtained from trees located in a commercial orchard from the commune of Santo Domingo, Valparaíso Region, Chile. The estimated disease incidence was 40%. From six symptomatic fruits, samples of peel and flesh tissue were taken from the advance zone of the lesions for pathogen isolation and identification. Based on morphological characteristics, DNA sequencing and pathogenicity test, the causal agent was identified as Neofusicoccum luteum. Stem-end rot disease was previously reported in California caused by N. luteum. In Chile, the disease was first reported by Montealegre et al. (2016) caused by Neofusicoccum australe and by Valencia et al. (2019) caused by Neofusicoccum parvum. This is thought to be the first report of N. luteum causing stem-end rot disease in avocado in Chile.