Spatial Distribution of Candidatus Liberibacter solanacearum and Bactericera cockerelli (Sulc) (Hemiptera: Triozidae) in Potato (Solanum tuberosum L.)

摘要

Zebra chip disease affects the production of potato (Solanum tuberosum L.) in Mexico and the southern United States. This disease has been associated with the bacterium Candidatus Liberibacter solanacearum and is vectored by the psyllid Bactericera cockerelli (Sulc). Its control is based on broadcast applications of insecticide because the distribution of the disease and its vector is unknown. In this study we determined the spatial distribution of B. cockerelli and Ca. Liberibacter solanacearum with geostatistical techniques and detection of bacterium by molecular techniques. At the end of the crop season, the centers and aggregation of this disease did not coincide with the three stages of the insect, because adults were aggregated in asymptomatic plants. The disease incidence in plot 1 was 57%, whereas in plot 2 it was 45%. In plot 2, the bacterium was detected in 11 of 66 asymptomatic plants. According to the results, the distribution of Ca. Liberibacter solanacearum and B. cockerelli presented different types of aggregation. Centers of aggregation of bacterium and the insect did not occur at the same point.