@article{Granados-Montero_Avelino_Arauz-Cavallini_Castro-Tanzi_Ureña_2020, title={Leaf litter and Mycena citricolor inoculum on the American leaf spot epidemic}, volume={31}, url={https://revistas.ucr.ac.cr/index.php/agromeso/article/view/36614}, DOI={10.15517/am.v31i1.36614}, abstractNote={<p><span class="CharOverride-4"><strong>Introduction.</strong> </span>The American leaf spot caused by <span class="CharOverride-5">Mycena citricolor</span> is among the main coffee diseases in Costa Rica. Cyclic attacks occur approximately every fourteen years, related to increased rainfall and inoculum. <strong><span class="CharOverride-4">Objective. </span></strong>Determine the impact of litterfall and primary inoculum on the epidemiology of this disease. <strong><span class="CharOverride-4">Materials and methods. </span></strong>In coffee plantations located in the coffee region of Tarrazú, Costa Rica, the effect of the manual elimination of diseased leaves attached to the plant and the layer of fallen leaves on the American leaf spot epidemic in 2013 and 2014 was assessed. 1200 branches were evaluated in an experiment of divided plots, where the four treatments were obtained by combining the “with and without” levels for each factor. The disease was described by quantifying the number of diseased leaves, lesions, and geminifers. The disease development curves were constructed and the area under the curve was calculated for each variable. The growth and defoliation of coffee plants was calculated.<strong><span class="CharOverride-4"> Results. </span></strong>Based on the disease incidence curve for each treatment in each year, it was determined that the logistic growth of epidemics is the best fit model. The rates of apparent infection (<span class="CharOverride-5">r</span>) were close to 0.04 units per day in 2013 and there was no significant statistical difference in the developed epidemics; but for 2014, where they varied between 0.03 and 0.05. A main effect of the initial inoculum factor was observed on the presence or absence of litterfall. <span class="CharOverride-4"><strong>Conclusion.</strong> </span>Litterfall had no significant effect on the development of the American leaf spot epidemic. This is the first investigation that determines the impact of possible sources of inoculum other than the lesions present in coffee leaves.</p>}, number={1}, journal={Agronomía Mesoamericana}, author={Granados-Montero, María del Milagro and Avelino, Jacques and Arauz-Cavallini, Felipe and Castro-Tanzi, Sebastián and Ureña, Natalia}, year={2020}, month={Jan.}, pages={77–94} }