Spatial parameters associated with the risk of banana bunchy top disease in smallholder systems

The Banana Bunchy Top Disease (BBTD), caused by the Banana Bunchy Top Virus (BBTV) is the most important and devastating in many tropical countries. BBTD epidemiology has been little studied, mixed landscape smallholder systems. The relative risks associated with this disease vary between geographical areas and landscapes. This work analyzed the management and vegetation conditions in smallholder gardens to assess the factors linked to landscape-level BBTV transmission and management. Mapping was done in this study area which is in a BBTD-endemic region, involving farmers actively managing the disease, but with household-level decision making. A spatial scanning statistic was used to detect and identify spatial groups at the 5% significance threshold, and a Poisson regression model was used to explore propagation vectors and the effect of surrounding vegetation and crop diversity. Spatial groups with high relative risk were identified in three communities, Dangbo, Houeyogbe, and Adjarra. Significant associations emerged between the BBTD prevalence and some crop diversity, seed systems, and BBTD management linked factors. The identified factors form important candidate management options for the detailed assessment of landscape-scale BBTD management in smallholder communities.

Automated summary

This study examined the management and vegetation conditions in smallholder gardens to assess factors linked to landscape-level BBTV transmission and management. Using mapping, spatial scanning statistics, and Poisson regression models, high-risk spatial groups were identified in three communities. Significant associations were found between BBTD prevalence and crop diversity, seed systems, and BBTD management factors, which are important for further assessment of landscape-scale BBTD management in smallholder communities.