Occurrence and Severity of Physiological Disorders of Oil Palm (Elaeis guineensis Jacq. L.) in Uganda

Abstract

In Africa, oil palm is grown in 25 countries supported by corporate investors. In Uganda, commercial oil palm cultivation began in 2005 in Bugala Islands. Seedlings were imported from countries with established breeding programs. These seedlings were grown in areas with different environmental conditions which have resulted in a number of physiological disorders. The aim of this research was to determine the major physiological disorders in oil palm fruit bunches in Uganda. The study was carried out in the adaptive trials in Kagadi, Bugiri, Buvuma and Masaka Districts and in the different smallholder farmer blocks in Kalangala District. Data was collected on bunch rot, bunch failure and uneven ripening. Sampling was carried out in oil palm plantations above five years of age. Three fields were selected from each unit and three units from each block by the help of the Agricultural Extension Officers (AEOs). Palms were randomly sampled and assessed for presence of bunch rot, bunch failure and uneven ripening symptoms. The incidence was expressed as a percentage of the total number of palms sampled while the severity of bunch rot disease was scored on a scale of 0-4. From the results, the differences in bunch rot and bunch failure in adaptive trials were statistically significant as well as across seasons (P < 0.05). Uneven ripening was not statistically significant and severity of bunch rot in the different farmer blocks in Kalangala was statistically significant (P = 0.03). Uneven ripening was high across smallholder farmer blocks in Kalangala and was statistically significant (P = 0.05) even across seasons (P < 0.05). These results are important for sensitization of farmers on management of oil palm disorders and essential for guiding policy makers and investors as the oil palm industrial sector is being developed in Uganda. This study calls for determination of water deficit at the various ecological zones and its relationship to physiological disorders as a guide for further oil palm estate development.

Challenges and Opportunities of Oil Palm Production in Uganda

“…Materials (varieties) grown in other countries have been found to respond differently in Uganda. These varieties have shown different yield attributes for size, number of bunches, un-even ripening, bunch rot all of which affect the production and productivity of oil palm [12].…”

“…Physiological disorders: A number of physiological disorders such as nonuniform ripening, bunch rot, and bunch failure have been identified in Uganda [12]. Non-uniform ripening leads to poor fresh fruit bunch quality and high free fatty acid levels which affects oil palm profitability due to the rejection of pour quality fruits at the factory [33].…”

“…Bunch rot is increasingly causing rotting of fruits before maturity among oil palm farmers in Uganda. The cause of the diseases has yet to be identified in Uganda but the major causes globally include Marasmius palmivora and "over bearing" in palms [12,53]. Other diseases of oil palm identified in Uganda include; Leaf spot, Leaf rust, Anthracnose and Blast.…”

“…Currently, oil palm production in Kalangala exceeds 11,000 hectares and the production has been expanded to the districts of Buvuma and Mayuge. Adaptability studies have revealed that production is suitable in Masaka, Kibaale, Bugiri, and Kagadi [11,12]. In Kalangala, over 6500 hectares belong to the private sector partner, Oil Palm Uganda Limited (OPUL) while over 5000 hectares belong to medium and small-scale farmers.…”