First report of Botrytis prunorum causing fruit rot on kiwifruit in Chile.
Kiwifruit (Actinidia deliciosa) is a high-value crop in Chile, the second major kiwifruit producer in the Southern Hemisphere, with over 9700 ha planted at present. Kiwifruit cv. Hayward, harvested in the Central Valley of Chile, stored for 120 days at 0°C in 2% O2 and 5% CO2 controlled atmosphere (CA) chambers, were infected with Botrytis fruit rot at 3 to 7% in 2015. Symptoms consisted of a light to dark brown soft watery decay that often started from the stem end and affected the pericarp and then the whole fruit. At room temperature (20 to 22°C), decayed fruits developed a white to gray fungal growth. Based on morphological characteristics, molecular data (genes glyceraldehyde-3-phosphate dehydrogenase, heat-shock protein 60 and DNA-dependent RNA polymerase subunit II) and pathogenicity, the causal agent was identified as B. prunorum. This is thought to be the first report of B. prunorum causing fruit rot on Hayward kiwifruits during CA storage. The frequency of B. prunorum was low (12.5%) and it was always found with B. cinerea. Previously, B. prunorum was identified on flowers of Japanese plums (Prunus salicina) in Chile.