Tropicultura (Jan 2015)
Distribution de la bactériose du cotonnier au Bénin et sensibilité des variétés locales à ses attaques
Abstract
Distribution of Cotton Bacterial Blight in Benin and Susceptibility of Local Varieties to its Attacks. In order to improve the production of cotton in Benin, Agricultural Research is continually developing varieties resistant to pests and diseases and adapted to the diversity of the local growing conditions. In this framework, surveys were conducted in 2012 in all cotton areas of Benin on 44 sites of 16 districts to detect bacterial blight strains. At least two sites were surveyed per district and on each site 30 and 10 plants were inspected randomly along the two diagonals of a cotton field, respectively for the incidence and severity. The results showed that cotton bacterial blight was present in 41 of 44 sites. The highest means for incidence (89.3%) and severity (62.6%) were observed in Alibori-Atacora area with the maximum incidence in the district of Banikoara and Kandi (100%). The Plateau-Couffo area recorded the lowest incidence with a null value at Ketou. In parallel with the achievement of the survey, a trial on susceptibility of seven varieties of cotton against three bacterial blight isolates selected for their virulence has been carried out under greenhouse conditions at the experimental farm of the faculty of agronomy in august 2012. The screening of varieties has been realized in a split plot design with isolate as principal factor and variety as secondary factor. Differential reactions were observed between isolates and varieties which may indicate the existence of races of the pathogen and resistance genes to it.
