Incidence and severity of major diseases of coffee in highland of eastern Ethiopia

Abstract
This study was conducted with the objective to assess the incidence and severity of coffee berry disease (CBD) and coffee leaf rust (CLR) in the highland of Eastern Ethiopia. In the east Hararge Zone of Eastern Ethiopia, coffee was grown by 331,651 holders on 7,584 ha with a production output of 3,722 tons and a yield of 0.5 ton/ha in 2017. Bedeno is the leading coffee producer district in the Zone followed by Melka-ballo, Deder and Meta districts. In Bedeno, coffee is mainly grown in altitudes ranging from 1690 to 2260 masl. Coffeeberry disease and leaf rust are the two major diseases of coffee in the area. A total of 34 representative coffee farms at nine study sites (3-4 coffee farms at the interval of 3-5 kilometers) were selected through discussion with Bedeno district’s coffee experts. The study sites were selected using sequential sampling techniques through discussions with the district’s coffee experts. Incidence of coffee berry disease and leaf rust was determined as percentage of diseased trees. Disease severity was determined as percentage of diseased coffee berries per plot. Data were analyzed using descriptive statistics. The result of this study revealed the incidence of CBD in Bedeno district ranged from 30.0 to 93.3% with a mean of 70.19%. The severity of the CBD was from 13.3% to 44.4% with an average severity of 28.53%. Both incidence and severity of CBD were high at Barkalle followed by Barakat and Hindhessa areas. On the other hand, the incidence of coffee leaf rust varied from 18.9 to 87.4% with a mean of 52.7%. The high mean incidence of CLR at highland areas of eastern Ethiopia is clear evidence for the occurrence of climate change in the area. Hence, it is advisable to introduce improved coffee varieties that are resistant to coffee berry disease and leaf rust for production in the area. Training farmers to implement proper cultural disease management practices such as prunning and sucker management will also help alleviate the constraint.