Symptomatology and pathogenicity of Phytophthora pod rot disease associated with Cacao plants in selected municipalities in the Province of Cagayan, Philippines

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Research Paper 06/05/2023
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Symptomatology and pathogenicity of Phytophthora pod rot disease associated with Cacao plants in selected municipalities in the Province of Cagayan, Philippines

Angelina T. Gonzales, Diosa G. Alasaas, Macluven T. Gonzales
J. Bio. Env. Sci.22( 5), 9-16, May 2023.
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The study aimed to describe the Phytophtora pod rot (PPR) symptoms disease associated with cacao plants and its pathogenicity to cacao. Specifically, it aimed to: (a) describe the PPR disease symptoms associated with cacao plants; (b) determine the pathogenicity of PPR disease to cacao seedlings, cacao flower and unripe and ripe pods; (c) document the reaction of cacao varieties to PPR disease. Samples isolated from infected cacao pods of five cacao farms revealed 14 isolates of Phythophthora spp. Pathogenicity test showed development of typical symptoms of Phythophthora of isolates from infected tissue of cacao pod. Incubation period was recorded between 4 days to 14 days after inoculation. The pathogen associated with Phythophthora pod rot belongs to Phythophthora palmivora. Cacao seedlings from 21-days old to 6 months manifested water-soaking leaves to leaf blighting symptoms, while infected flowers were found to have blighting and necrotic symptoms. Ripe variety could easily infected compared to unripe pod as shown by oily brown appearance and it changes from brown to black. White leathery structure or whitish appearance (sporangia) on the surface of the pods and mummified pods in advance stages.


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