Distribution, Incidence and Severity of Covered Kernel Smut and Reaction of Some Sorghum Genotypes to the Disease in Northwest Ethiopia

Abstract

The study was made to survey the distribution, incidence and severity of covered kernel smut on sorghum fields in Gondar Zuria and Alefa Takussa districts of North Gondar Zone, Amhara Region in northwestern Ethiopia. In addition, the study aimed to assess the reaction of sorghum genotypes to the disease. Sampling for the field survey was made by randomly selecting 11 peasant associations (PAs) from each district and 10 farmers’ fields from each PA. In Gondar Zuria district, the disease was highly distributed throughout the surveyed areas. The disease incidence among the PAs ranged from 10.5% at Tach Teda to 29.2% at Sarwuha. There was highest disease severity at Bahri Ginb (54.66%) and lowest at Sarwuha (26.57%). In Alefa Takussa district, the disease was distributed through out the area with mean incidence of 12.25%. The highest incidence was at Goy (17.43%) and the lowest at Chima Lembez (5.5%).
The highest disease severity was encountered at Ayibiga (48.35%) and the lowest at Chima Lembez (31.05%). Nine local cultivars were encountered during the survey. Four of the cultivars — Aysham Demozie, Bulie, Kuche/Tabir, and Zengada/Dinkosh — were distributed in the surveyed districts. Cultivars Tetron and Zengada/Dinkosh scored lower mean incidence of 3 and 9% and severity of 23 and 31%, respectively. In addition, the reaction of 12 improved and local sorghum genotypes to the disease was studied under artificial inoculation at Babile Research Sub-center, eastern Ethiopia, in 2000/2001. The local cultivar Tetron was resistant and Zengada/Dinkosh moderately resistant. Whereas, the other genotypes were susceptible. Moreover, the cultivars differed in yield loss due to the disease. There was highest yield loss (40%) on 97 MW 6129(NVT-11 4), while there was no loss on Tetron.