Survey on Distribution and Significance of Garlic White Rot (Sclerotium cepivorum Berk) in East and Southeast Tigray Highlands, Northern Ethiopia

Abstract

White rot caused by a soil borne fungus (Sclerotium cepivorum Berk.) is a major productionthreat of garlic wherever the crop is grown. The objectives of this study were to map thedistribution and quantify the incidence and prevalence of garlic white rot in major garlicgrowing districts of Tigary and to determine the associated factors. Survey was conducted insix districts of Tigray namely Hintalowajrat, Enderta, Atsbiwemberta, Gulemekeda,Deguatembien and Ganta-Afeshum in the main cropping season between 20 September to 5October in 2010. A total of 137 garlic fields were inspected. Number of fields inspected perdistrict ranged between 11 and 36. Fields were selected by purposive sampling techniquesfrom each of the surveyed districts and growers were interviewed using semi structurequestioner to obtain information on cropping systems and cultural practices. Survey resultsindicated that white rot was found widely distributed in all garlic growing districts. Plantingtime and crop density affected the distribution and incidence of the disease. Incidence withvalues of 52 % and 53% were high in Hintalowajrat and Ganta-Afeshum compared toincidence of 32 and 38% in Enderta and Gulemekeda districts, respectively. High white rotincidence was associated with high crop density (>33 plants m -2 ) and in June and Julyplanting. Incidence was low in May planted garlic and low garlic population (< 33 per m -2)field. Further independent research on effect of plant spacing and planting time is needed toverify as an integral component of white rot management in garlic in Tigray and elsewherewith similar agro-ecological settings.