The aim of this study was to examine the impact of both organic and inorganic nitrogen fertilizers on the intensity and epidemiological components of Cercospora leaf spot across three different canopies of cotton plants, specifically the variety DP ACALA 90, under field conditions. Fertilizers used in the study included bovine manure, Jatropha curcas seedcake, poultry manure, and urea (the latter serving as a control). These were applied at 20 days after plant emergence and then during the flowering stage until the total nitrogen (N) dose reached 50, 100, 150, or 200 kg N per hectare. The incidence and severity of the disease were assessed starting at the reproductive stage B1 (the first visible flower bud) across the lower, middle, and upper canopies of four cotton plants, with six evaluations conducted over time. To calculate the initial inoculum (Y0) and the disease progress rate (r),...

Throughout history, the cocoa crop (Theobroma cacao L.) has been affected by countless diseases, some of these caused by Lasiodiplodia theobromae (Pat.) Griffon & Maul. Although three Lasiodiplodia species have been reported affecting cocoa plants, L. theobromae is the most studied species both in cocoa and other crops. In recent years this phytopathogen has been gaining importance. In cocoa, L. theobromae can survive in soil and culture remains in the form of pycnidia and chlamydospores, spreading by different factors until reaching the plant tissues, remaining there as an endophyte. The pathogenic fungus can cause young twigs death (a characteristic symptom found in field conditions), fruits rot and mummification, and even vascular dieback. In general, the management of pathogens of the Botryosphaeriaceae family is complex, even more so when the pathogen is already present in the c...

Cocoa (Theobroma cacao L.) is one of the main crops in Latin American and African countries, its almonds being marketed to produce chocolate. However, different biotic factors can negatively affect the crop production, especially on small farms where management by farmers is scarce or nonexistent. Lethal wilt (Ceratocystis cacaofunesta Engelbrecht & Harrington) together with beetle borers (Coleoptera: Curculionidae: Scolytinae), continue to be the main problems affecting cocoa. It has been observed that both organisms interact intrinsically inside the trunks of cacao trees. Despite the importance of this interaction, in general, the countless research and review articles carried out to date have focused mainly on studying each biotic factor separately or have been addressed in a general way. Thus, in this review we mainly focus on the interaction between the Lethal wilt and the borer...

Coffee (Coffea spp.) is the second most significant commodity worldwide, with C. arabica being its most representative species. The coffee crop is affected by different fungal diseases that reduce the photosynthetically active area of its leaves and the production of grains. In order of agronomic importance, the rust caused by the biotrophic pathogen Hemileia vastatrix is a disease difficult to manage due to its type of reproduction. Another no less important, Thread Blight, caused by the basidiomycetes Ceratobasidium noxium (Syn. Corticium koleroga) and C. chavesanum, affects all aerial tissues of plants. The third disease, Cercospora leaf spot caused by Cercospora coffeicola, affects both leaves and grains, making it difficult to manage. Although there is enough scientific information on Rust, very little is known about the etiology, symptomatology, life cycle, and management of Thread...

The genus Capsicum, native to tropical and subtropical America, belongs to the Solanaceae family, which includes commercially important vegetables such as chilies and green peppers. The silverleaf whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), causes losses to vegetables including Capsicum species. Among the alternatives of pest control, an effective, economical, and environmentally compatible method is the resistance of the host plant. Infestation by B. tabaci was evaluated in 73 Capsicum genotypes, corresponding to the species C. annuum, C. baccatum, C. sinense, C. frutescens and C. pubescens from an Ecuadorian genebank. Eighty-four percent of the C. baccatum genotypes evaluated showed the highest population densities of B. tabaci, while all the genotypes of C. sinense and C. frutescens had the lowest values (p < 0.05). The non-preference of adults and the scarce ovip...

The Musaceae family is susceptible to Fusarium wilt (Fw), which is considered the most important disease globally, caused by a group of Fusarium species that includes F. oxysporum f. sp. cubense tropical race 4 (FocTR4). Until recently, FocTR4 was not present in Latin America. However, wilting, chlorosis of leaves, and vascular discoloration (typical symptoms of Fw) were observed in at least a hundred Cavendish plants located in Colombia, Peru and Venezuela in 2019, 2021 and 2022, respectively. Normally, the disease is more severe throughout the warmer and rainy months of the year. Since Ecuador is the world's leading exporter of bananas, including plantains, this study aimed to identify agroclimatic favorability zones for FocTR4 potential incidence in the country, testing linear models to evaluate disease occurrence in relation to climatic conditions and map favorability zones. Most of ...

Oil palm (Elaeis guineensis L.) is a crucial crop in Ecuador, considerably affected by black palm weevil Rhynchophorus palmarum L. (Coleoptera: Curculionidae) for several years. Despite its importance, the behavior of the black weevil in Ecuador is not well comprehended presently. Therefore, this study aimed to predict infestation patterns of the black palm weevil in Ecuador using a mathematical model based on monitoring data. Data on the number of insects per trap from a commercial oil palm farm in Quinindé, Ecuador, was collected every two weeks for five years (2016-2020) and analyzed using the Classical Fourier (CF) spectrum and the Dickey-Fuller test to determine seasonality. The trend component of the data dropped from 16.33 in January 2017 to 11.96 in January 2019, with a fluctuation ranging from -0.11 to 2.50 observed for the entire data set. The results obtained after fitting th...

Wetlands worldwide face increasing challenges due to human activities such as water extraction, deforestation, and overfishing. These ecosystems are crucial for biodiversity, water retention, and purification. In Ecuador, the “Abras de Mantequilla” wetland exemplifies these pressures. It serves as a vital site for studying the interactions between soil fertility and arbuscular mycorrhizal fungi (AMF) in forest ecosystems. The study focused on the soil fertility, particularly in relation to AMF in "Noah Morán" secondary forest within the Abras de Mantequilla wetland. The key role of AMF in improving soil fertility was highlighted. Soil samples were collected from the root zone of four forest tree species i.e., Guazuma ulmifolia, Albizia guachapele, Eugenia pustulescens, Cecropia peltate. The four investigated soil samples had marginal differences in the soil physicochemical propertie...