Effects of anthracnose disease on avocado production in Kenya

• Main Authors: K. S Kimaru, K. P Muchemi, J. W Mwangi
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2020-01-01
• Series: Cogent Food & Agriculture
• Subjects: avocado; anthracnose; control; virulence; epidemiology; production
• Online Access: http://dx.doi.org/10.1080/23311932.2020.1799531

Avocado production has increased exponentially over the years worldwide. This has been necessitated by the various uses of avocado fruits other than as a source of nutrients which includes pharmaceutical, cosmetic and oil industries. These various uses of avocado have resulted to improved livelihood in terms of income generation. Increased avocado production worldwide has been at the expense of other tree and food crops. In Kenya, it is attributed to decreased acreage of key cash crops such as coffee and tea as well as staple food crops such as maize and beans. Avocado production, however, has been faced by several constraints such as poor rootstalks, diseases, pests, abiotic factors, poor harvesting technology, poor handling of harvested fruits and post-harvest diseases. All these challenges lead to poor fruit quality at the market both local and export market leading to losses economically. Of major concern is anthracnose disease caused by Colletotrichum gloeosporioides, Colletotrichum boninense, Pestalotiopsis microspora both in the field and after harvest. The disease is associated with 60% losses as a result of abortion of fruits in the field and post-harvest rots. Limited studies on the the interaction of the causal agents, the disease cycle and its epidemiology in Kenya, has rendered disease management impractical. Control of this disease has been through pruning and sorting of the diseased fruits. However, majority of the farmers do not apply any control measures. Furthermore, the use of chemical control has been limited due to a lack of available fungicides registered for use in Kenya. Fruit rots and quality issues due to black spots has affected the marketability of avocado fruits in the export market mainly EU market. Due to this, the avocado farmer in Kenya has been receiving low returns from their avocado export. Further understanding of the anthracnose disease epidemiology, virulence and genetic variation of the causal agent and the sensitivity of the causal agent to available fungicides will enhance the effectiveness of the anthracnose disease management, resulting in improved avocado productivity.