White mold caused by Sclerotinia sclerotiorum is an important disease for many crops worldwide, but particularly for soybeans in the Americas. In Brazil, the disease expanded geographically in the last eight years, and is currently present in around one fourth of the soybean areas of the country. In North America, few studies have focused on the relationship between disease incidence and yield, but it was not known whether the estimates are valid for tropical and subtropical conditions. Research efforts on soybean white mold increased in the last decade in Brazil, especially focusing on disease control methods. However, quantitative summaries of soybean yield and fungal sclerotia (a fungal sexual structure) due to the disease were not available.
Last year we began study these relationships (following our experience with the technique in this paper) in a large data set of fungicide trials conducted over four growing seasons and several locations in Brazil. Through meta-analysis we were able to obtain mean estimates of intercepts and slopes for both relationships and explore epidemiological and study-specific factors affecting the estimates.
The work was conducted in collaboration with our colleagues at the Epidemiology of Vegetable Diseases Lab (EVADE, Dr. Pethybridge, Cornell, NY). The study has been [published in Plant Pathology[(http://onlinelibrary.wiley.com/wol1/doi/10.1111/ppa.12590/abstract)]. All data and R codes used in the paper will soon be available at our GitHub account.