Spatiotemporal analysis of meteorological drivers of major foliar fungal diseases in rubber budwood gardens in Cote D'Ivoire

Latex production in Côte d'Ivoire is significantly influenced by meteorological conditions and various diseases, particularly foliar fungal diseases affecting Hevea brasiliensis, which can cause yield losses of up to 100%. This study aims to identify the climatic factors driving the severity of these diseases across different ecological zones. Surveys were conducted in budwood gardens (JBG) across six agroecological zones, with meteorological data collected on-site. The analysis identified Helminthosporium heveae, Colletotrichum gloeosporioides, and Corynespora cassiicola as the most prevalent fungi, exhibiting high incidence and severity in key production areas such as Tabou and Nouamou. Multiple regression analyses revealed that rainfall and relative humidity (correlation coefficients ranging from 0.4 to 0.55, p 0.0001) and leaf wetness duration (correlation coefficient 0.7, p 0.0001) are critical predictors of disease severity. Specifically, each additional unit of leaf wetness increased infection severity by 0.642 for H. heveae, 0.435 for C. gloeosporioides, and 0.832 for C. cassiicola. These findings underscore the importance of meteorological factors in disease development and could support the establishment of early warning systems to manage foliar fungal diseases of H. brasiliensis in Côte d'Ivoire.