Utilisation de Crotalaria spectabilis contre le flétrissement bactérien (Ralstonia solanacearum) de la pomme de terre dans la zone de Betafo

In Madagascar, bacterial wilt caused by the soil-borne species complexe Ralstonia solanacearum is a serious disease of potato in main production areas. The present study aimed at assessing biocontrol potential of the legume cover crops Crotalaria spectabilis against bacterial wilt of the variety Meva of potato. The field study was carried out at two sites located in the Betafo district, in the Vakinankaratra region, on andosol. The experimental design was a randomized complete block design with two treatments and four replicates. Treatments were consisted of the sole cropping of potato and the mixed cropping potato*Crotalaria spectabilis in alternate rows, respectively. Results showed potato growth promoting and bacterial wilt (R solanacearum phylotype I, biovar 3) biocontrol effects of mixed system. Increased potato total tubers (129%) and marketable tubers (114%) yields and decreased incidence (71%) and severity (63%) of potato bacterial wilt were recorded in mixed system as compared to sole cropping.

Key-words:Cultural control, Crotalaria spectabilis, bacterial wilt, mixture, potato, resistance, Ralstonia solanacearum

18/01/2024