Progress in breeding cotton cultivars resistant to bacterial blight in Nigeria
1990
Poswal, M.A.T. (Institute for Agricultural Research, Zaria (Nigeria). Dept. of Crop Protection)
Bacterial blight of cotton is the most economically important disease of cotton in Nigeria. The disease is estimated to cause an annual yield loss of 10-20 percent. The development and use of resistant cultivars is the most economic means of disease control. Breeding cotton cultivars resistant to bacterial blight has been an integral part of the cotton improvement programme in Nigeria. Over the last 60 years, eight commercial cultivars varying in levels of resistance to bacterial blight were released. The current two commercial cultivars (Samaru 71 and Samaru 77) are presently susceptible to the evolution of virulent strains of the pathogen. Over the past two decades, six cotton hybrid pools (ASA, AASA, ACSA, RSA, RASA and SMSA) were developed and now form the genetic pool for the current cotton varietal improvement programme. Advanced breeding lines with improved levels of bacterial blight resistance, yield and fibre qualities have been identified within some of the hybrid pools. The recent introductions of the short-seasoned, multi-adversity resistant (MAR) cotton from Texas, U.S.A., and the cultivar S295 from Chad, will be valuable in reinforcing and enhancing the progress in developing cotton cultivars resistant to bacterial blight, other diseases, insect pests and environmental stresses in Nigeria
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