Submitted to: Phytopathology
Publication Type: Proceedings
Publication Acceptance Date: 5/5/2004
Publication Date: 8/20/2004
Citation: Keith, L.M., Zee, F.T. 2004. Hawaiian grown guava as a model for studying plant disease. Meeting Abstract. American Phytopathological Society Annual Meeting 94:S50.
Technical Abstract: Guava is one of the most vigorous and widespread plants in the tropics and is associated with many fruit rot diseases. Guava is commonly processed into puree and juice so disease can decrease its marketability. In Hawaii, common guava (Psidium guajava L.) is found throughout the island at a variety of elevations and environmental conditions. Due to its widespread distribution, guava serves as an excellent model for studying disease. A survey was conducted at the Waiakea Agricultural Experiment Station where there are 50 accessions of guava grown. Disease symptoms were visible on leaves without fruit present and on the skin of young fruits which progressed as fruits matured. Disease ratings were developed to describe symptom severity. Samples of fruit and leaves were collected, photographed and aseptically cultured on potato dextrose agar. One of the main fungi consistently isolated from leaves and fruit was Pestalotiopsis sp. Morphology, colony characteristics, and pathogenicity of the isolates was examined and potential sources of host resistance were identified for germplasm characterization studies. The importance of Pestalotiopsis as a guava pathogen and its cross-infection potential will be discussed.