Authors: Suhaida, S., Yanazlinda Ayuni M. N. and Aizat J.

Journal Issue: Malaysian Cocoa Journal, Volume 15(1)/2023

Keywords: cocoa, Phytophthora palmivora, black pod, stem canker, seedling blight

Published On: 27/10/2023


Phytophthora spp. are responsible for some serious diseases of cocoa including black pod, stem canker, seedling blight, leaf blight and chupon wilt. Eight species of Phytophthora have been isolated from diseased cocoa worldwide, even though only three species cause most losses in cocoa production which are P. palmivora, P. megakarya and P. citropthora. In this study, seven isolates of Phytophthora sp. were isolated from black pod, stem canker and seedling blight collected from Cocoa Research and Development Centre (CRDC) Jengka, Pahang, Malaysia. All isolates were incubated on potato dextrose agar (PDA), corn meal agar (CMA) and carrot agar (CA) to observed their macro-morphology on different media. They were then identified using their micro-morphological characteristics and it was concluded that all of the isolates are P. palmivora. The growth rate of all isolates were faster when incubated on CA, ranged from 1.17 – 1.42 mm/day, compared to CMA (1.07 – 1.20 mm/day) and PDA (0.43 – 0.75 mm/day). The colony morphology of P. palmivora in PDA is white fluffy with concentric rings and irregular margins, while on CMA is white and scanty fluffy colonies. Meanwhile, all isolates produced white dense rosettes of hyphae when grew on CA.

Malaysian Cocoa Journal

Volume 15(1)/2023

ISSN 1675-5650