Leaf blight and stem canker of Mangosteen in Hawaii
L. Keith (1), L. SUGIYAMA (1), T. Matsumoto (1)
(1) USDA-ARS, Hilo, HI, U.S.A.
Phytopathology 101:S89

Mangosteen (Garcinia mangostana Linn.) is a tropical evergreen tree that produces one of the most praised tropical fruits, commonly known as the “Queen of Fruit”. Mangosteen has the potential to occupy a rapidly expanding niche market in Hawaii. The aim of this study was to identify the causative agent of the leaf spots and stem cankers in Mangosteen trees ranging in age from newly planted to 6+ years old. Symptoms were observed in a Mangosteen orchard on the Hamakua Coast of the Island of Hawaii, approximately 6 miles north of Hilo. Single spore isolations from leaf lesions and stem cankers resulted in pure cultures of the fungus. The fungus was identified as Pestalotiopsis sp. based on morphological characteristics and molecular analysis. Pathogenicity tests with the isolated fungus showed identical leaf symptoms on 3 year old seedlings growing in a hoophouse. Pestalotiopsis leaf blight has already been reported in other countries growing Mangosteen. However, this is the first report of Pestalotiopsis leaf blight and stem canker on Mangosteen in Hawaii.