Coffee Fight: a new approach to controlling coffee rust

Abstract

Brazil is the largest producer and exporter of coffee in the world. However, the productivity of this crop can be reduced by rust, caused by the fungus Hemileia vastatrix, the main coffee disease worldwide and by cercosporiosis, caused by the fungus (Cercospora coffeeicola). The use of fungicides is the main method for fungal disease control these diseases in crops in susceptible cultivars. Previous studies conducted in a growth chamber and greenhouse throughout 2019 and 2020 led to the formulation of a cálcium-based mixture that was called Coffee Fight. The application of Coffee Fight reduced the severity of rust and cercospora. Morphological evaluations showed that, after a certain concentration of Coffee Fight, the thickness of the cell wall increased, and this may have been responsible for the reduction in the severity of the disease was reduced. This may be the result of the strong binding of calcium in the non-esterified chains of homogalactorans that make up the pectic portion of cell walls. Based on this study, we developed a product based on calcium to be applied to coffee trees, which, in previous experiments, seems to have the ability to reduce the severity of the disease in coffee seedlings, although the mechanisms for this have not yet been elucidated. The main objectives of this PIPE project are: (i) to develop the formulation of a product, called Coffee Fight, based on soluble calcium, for the prevention and control of coffee rust and cercosporiosis (ii) to evaluate in the field conditions the best doses and Coffee Fight application program to achieve high calcium content, assessing the reduction in the incidence of rust and cercosporiosis (iii) unraveling the effect of Coffee Fight on pectins. This product is differentiated by Ca-based formulation and high-performance adjuvants and will be formulated and adjusted to provide not only plant nutrition but also a reduction in the severity of rust and cercosporiosis. In this way, the project aims, in a multidisciplinary line of work, to generate knowledge that can serve for the improvement in the management of diseases of the coffee culture, producing a sustainable and environmentally safe coffee culture. (AU)