Aims: Oil palm (Elaeis guineensis) is the most productive and the highest yielding edible oil crop in the world and economic crop cultivated in Ghana. In September 2017, an outbreak of leaf spot caused by Pestalotiopsis sp. on oil palm seedlings was reported for the first time in Ghana. The disease incidence reached 85%, assuming an epidemic situation. This study is geared towards developing appropriate management strategies by identifying phytopathogenic fungi that caused leaf spot on oil palm seedlings. Methodology and results: Ten symptomatic leaves were picked per plot into sterilized plastic Ziploc bags and brought to laboratory. The leaves were washed under running tap water, cut into 1 cm pieces each, surface-sterilized with 10% sodium hypochlorite solution, rinsed three times in sterile distilled water and blotted on tissue paper (Gonthier et al., 2001). The sterilized samples were transferred aseptically onto potato dextrose agar (PDA) plate containing 0.5 mg/L of chloramphenicol and subcultured till pure culture was obtained. The result showed pure white colony which was concentric, cottony and velvety with slimy black dots of conidia mass on the tip of aerial mycelia. The fungus isolated and identified from the lesions on the leaf was Pestalotiopsis sp. and its pathogenicity confirmed. Conclusion, significance and impact of study: The result from the study concludes that Pestalotiopsis sp. could infect E. guineensis, which developed the same symptoms observed naturally in the field after inoculation. The fungus was identified based on morphological characteristics.

Coconut (Cocos nucifera L.) is an important oilseed and a multipurpose perennial plantation crop. It is mostly grown in humid and coastal areas of Ghana. In June 2019, leaf spot disease was observed on coconut seedlings in 10 coconut growing Districts in Ghana. The Initial symptoms appeared as elliptical, brown-dark-red lesions, 4 -6 mm on affected leaves. Lesions reached 2.0 cm and gradually developed into spindly, dark brown spots with a light tan centre. A study including survey and laboratory work was carried out to assess disease prevalence and to identify the causal agent of the disease on coconut seedlings, in order to formulate effective management strategies against it. A total of 250 symptomatic leaves were picked from ten selected Districts for laboratory analysis. Additionally, the ribosomal internal transcribed spacer (ITS) region and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) of the isolated pathogen were amplified using ITS1 and ITS4, gpd1 and gpd2 primers respectively. The disease incidence peaked at 95%. Fungal colonies on PDA grew to 50 -70 mm in diameter in one week at a temperature of 28˚C ± 1˚C with an even to undulating, immersed striated, mycelium; aerial mycelium being dark velvety green and sometime woolly-cottony. Acervuli formed on the aerial mycelium and contained black powderish conidial masses. Hyphae characteristics were similar to that of Curvularia pseudobrachyspora.Pathogenicity tests were done following Koch's postulate. For molecular confirmation, the combined ITS (MT075719) and GAPDH (MT075720) sequences were compared with published sequences of 52 Curvularia isolates and eight Bipolaris isolates using phylogenetic analysis. This is the first report of C. pseudobrachyspora as a causal agent of leaf spot on coconut seedlings in Ghana and possibly Africa but the pathogen has been reported on other crops in China, Florida and India.

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