Comportamiento de genotipos de yuca frente a la enfermedad del mosaico africano de la yuca en Namibe, Angola

The response of 19 foreign genotypes and 21 national genotypes to the African cassava mosaic virus (ACMV) was evaluated, and the disease incidence and severity were analyzed. The total number of the plants planted by genotypes at the Namibe Agricultural Experiment Station, Angola, was sampled in February 2017, June 2017, and February 2018. The whitefly adult density per genotype was averaged to calculate the density index on each date, which was compared using a simple analysis of variance and the Duncan´s multiple range test for a confidence level of 95 %. The cluster analysis showed that the genotypes were grouped according to the disease severity. Some genotypes were detected with high severity indexes (0.8-1); however, TMS-84004, TMS-0276, TMS-300027, TMS-40142, TMS-800098, TMS-3021, TMS-300027, TMS-42025, Mz-3, Kassakala, and Canfufu, showed severity indexes of 0.2, the lowest index obtained. This result allowed suggesting genotypes that under high vector density conditions showed lower rates of disease severity, which can be used under adequate pest management conditions.