Pollinator conservation through nutrient substrates: A strategy for sustainable cocoa production Karla Michelle Barberán Sánchez, Evelyn Alexandra Espinoza Alcivar, Silvia Lorena Montero Cedeño, Ernerto Gonzalo Cañarte Bermúdez, José Bernardo Navarrete Cedeño Ecological Engineering and Environmental Technology, 2025 The purpose of this research was to evaluate the impact of the use of nutritious substrates on the conservation of cocoa pollinators, particularly of the Ceratopogonidae family, as a strategy to improve the productivity and sustainability of the crop.The research was carried out in a 20-year-old cocoa plantation located in Manab, Ecuador, during an annual cycle.A randomized complete block design (RCBD) with a 2 3 factorial arrangement was used, considering two types of cocoa (Nacional and CCN-51 clones) and three types of substrates (cocoa husk, plantain/ banana pseudostem and leaf litter).Pyramid traps were used to capture pollinators and parameters of flowering, pollination, fertilization and fruit formation were recorded in 75 trees per cocoa type.During the study, 7876 individuals belonging to the Ceratopogonidae family were captured, predominantly the genus Dasyhelea.The substrate composed of plantain/banana pseudostems attracted the highest number of pollinators, highlighting its potential as a favorable medium for conservation.In terms of clone yield, CCN-51 showed higher flowering (up to 165 flowers per tree) and higher dry yield (2326 kg/ha).On the other hand, the Nacional clones showed better pollination (20.56 %), fertilization (7.31 %) and fruit formation (3.34 %) rates, highlighting their biological efficiency in production.One of the main limitations of the study was its development in a single area and annual cycle, which restricts the generalizability of the results.However, the practical value of the research lies in demonstrating that the management of agricultural residues can enhance pollination ecosystem services and, consequently, improve cocoa productivity.This strategy represents a sustainable, original and relevant alternative to strengthen cocoa production through the conservation of its pollinators.
Performance of the Cotton Variety BRS-336 Under Different Seed Densities Gilmar Jesus Canarte-Canarte, Ernesto Gonzalo Canarte-Bermudez, Jose Bernardo Navarrete-Cedeno, Luis Fernando Diaz-Toral, Carlos Eddy Alvarado-Zamora, Fernando David Sanchez-Mora Sarhad Journal of Agriculture, 2024 C otton, Gossypium hirsutum
Application Frequency and Dosage of Mepiquat Chloride as a Growth Regulator for Coker Cotton Variety in Ecuador Luis Fernando Diaz-Toral, Carlos Eddy Alvarado-Zamora, Ernesto Gonzalo Canarte-Bermudez, Jose Bernardo Navarrete-Cedeno, Gilmar Jesus Canarte-Canarte, Fernando David Sanchez-Mora Sarhad Journal of Agriculture, 2024 All pesticides sold or distributed in the United States must be registered by EPA, based on scientific studies showing that they can be used without posing unreasonable risks to people or the environment. Because of advances in scientific knowledge, the law requires that pesticides which were first registered before November 1, 1984, be reregistered to ensure that they meet today's more stringent standards.
Agronomic Performance, Adaptability, and Stability of Maize Hybrids under Tropical Conditions in Ecuador Ricardo Limongi Andrade, Fernando David Sanchez-Mora, Raúl V. Mora Yela, José Pico Mendoza, Bernardo Navarrete Cedeño, Daniel Alarcón Cobeña, Geover Peña Monserrate, Jim Ochoa Ramos, Iris Perez-Almeida, Felipe R. Garcés-Fiallos Ciencia Tecnologia Agropecuaria, 2024 El maíz es uno de los cereales más sembrados y consumidos a nivel mundial. Las condiciones ambientales juegan un papel esencial en la interacción genotipo × ambiente y su potencial productivo. Durante la época lluviosa de 2016, 2017 y 2018, se evaluó el potencial agronómico, fitosanitario, productivo y adaptativo en 18 híbridos de maíz amarillo, en cinco localidades de ambiente tropical: Lodana, Jipijapa y Tosagua (Manabí); Mocache (Los Ríos); y Zapotillo (Loja). Para determinar el efecto de híbridos entre y dentro ambientes se utilizó el análisis de varianza y la prueba de Tukey (p <0,05). Los parámetros de adaptabilidad y estabilidad se estimaron mediante la regresión bisegmentada. Las características fitosanitarias se correlacionaron significativamente con las productivas. El rendimiento de grano se correlacionó con altura de inserción de la mazorca, plantas cosechadas por parcela, número de mazorcas cosechadas, aspecto de mazorca y roya. La interacción genotipo × ambiente mostró una respuesta diferenciada de los híbridos en cada ambiente. El genotipo G1 (G.I.2.10-1-1-1xL.I.4) se adaptó mejor a la mayoría de las localidades, mostrando rendimientos mayores que los demás materiales. El genotipo G10 (G.I.3.39-3-1-1xPORT.PHAEO.1AS2.4-1-1-1) respondió mejor a los ambientes favorables. Los híbridos prometedores G1, G2, G3, G5, G7, G9 y G11 podrían ser de interés para entornos favorables, mientras G8 podría explorarse para entornos desfavorables. Jipijapa y Tosagua (Manabí) y Zapotillo (Loja) mostraron un mejor desempeño en la producción de maíz, en al menos dos años de evaluación, siendo Tosagua la más estable para producir híbridos de maíz en el Ecuador.
Productivity of Cotton in Association with Food Crops in Soil without Nutritional Assistances Silvia Montero Cedeño, Ernesto Cañarte-Bermudez, Jose Navarrete Cedeño Journal of Ecological Engineering, 2023 Intercropped systems have agro-ecological and socioeconomic advantages over monocultures. Cotton is used in systems associated with food crops as an option to increase sustainability in family farming. The objective of this research was to evaluate the productivity of cotton in association with food crops, without using any nutritional assistance in the soil. This study was conducted on the rainy season of 2020 in Manabí-Ecuador. Six treatments were performed: four treatments related with the association of cotton with peanut, cowpea bean, field corn, and sweet corn; and two treatments with cotton monoculture (with and without soil fertilization). Agronomic, productive, and phytosanitary variables were evaluated in 60 m 2 experimental plots. A randomized complete block design with four replications was used. The results determined that cotton yield in the association with peanut was significantly equal to the monoculture with and without fertilization. In the intercropped food crops, there was a reduction in production in relation to the monocultures. However, it was the peanut in association with cotton with the lowest reduction, in addition to presenting the best Land Equivalence Ratio (1.71) and the best Marginal Rate of Return (120.56%), which suggests that this association is a viable alternative and easy to adopt by the small cotton producer.
Interaction between the incidence of Prodiplosis longifila Gagné (Diptera: Cecidomyiidae) and management practices in tomato crops in Manabí, Ecuador Gonzalo Bolívar, Ernesto Cañarte, Luis Duicela, José Navarrete Revista De La Facultad De Agronomia, 2022 The insect pest Prodiplosis longifila Gagné (Diptera: Cecidomyiidae), causes severe losses to the tomato crop in Ecuador, in the provinces of Manabí, Pichincha, Carchi, Cotopaxi, Azuay, and Chimborazo, where the main producing areas of this solanaceous crop in the country are located. The objective of this research was to study the interaction of the incidence of this pest with tomato crop management practices. The evaluations were carried out in twenty-five production units in different cantons of Manabí: in Bolívar (two), Portoviejo (eight), Rocafuerte (five), Santa Ana (one), Sucre (three) and Tosagua (six). Each unit had an area of 2500 m2, where 25 plants were randomly marked and the number of healthy, infested and damaged shoots was recorded, as well as the number of healthy and damaged fruits. In addition, a survey was applied to growers to determine the management practices carried out during the crop cycle. Descriptive analysis, significance tests, hierarchical clustering and chi-square tests were carried out. It was determined that in the cantons of Portoviejo, Tosagua and Rocafuerte, infestations did not exceed 13 % and a severity of up to 15 %, reaching 25 % of damaged fruit in Tosagua. The agronomic practices applied were trellising, drip and gravity irrigation, collection of infested fruit and chemical insecticides. There was an interaction with P. longifila between infested fruit collection and trellising, which influenced its infestation and severity, respectively. These incidences were significantly high at harvest, where highly toxic insecticide applications were substantially increased indiscriminately.
Ceratopogonidae: their role in pollination and fertilization at various technological levels of Theobroma cacao L. production Silvia Montero-Cedeño, Ernesto Cañarte-Bermudez, José Navarrete-Cedeño, Antonio Pinargote-Borrero, Pedro Sanchez-Hernández Revista De La Facultad De Agronomia, 2022 The goal of this study was to evaluate the role of pollinators on the pollination, fertilization and fruit set process in three technological production levels and three reproduction substrates, determinants in cocoa yield. Two pollination techniques (natural and assisted) were compared and as a control, flowers were isolated with antiaphid. Twenty-seven observation units were formed, with three biological replicates. A known number of flowers were evaluated 6, 14, 21 and 36 days after the opening of each flower on marked branches. The number of active flowers, pollinated, fertilized and fruits formed was recorded. Pollinators present in experimental units were collected using yellow sticky cards, then taken to the lab and identified. Pollination occurred up to three days after opening, the flower that remained with the ovary swollen and attached to the branch/stem was considered pollinated. Fertilization was recorded fourteen days after flower opening, fruit set begins after fertilization, an event that was quantified twenty-one days after flower opening. The systems studied did not influence the percentage of pollination, fertilization and fruit formation. However, the substrates did influence pollination, fertilization and fruit set. The assisted pollination technique is significantly superior to natural pollination. The same species of Ceratopogonidae were reported at all three levels and substrates, with genera Forcipomyia and Dasyhelea being the most abundant.
Molecular characterization of mahogany tree (Swietenia macrophylla King, Meliaceae) in the remnant natural forest of Ecuador Ricardo Limongi Andrade, José Pico-Mendoza, Eduardo Morillo, Johanna Buitrón, Santiago Meneses, Bernardo Navarrete, Miryan Pinoargote, Basilio Carrasco Neotropical Biodiversity, 2022 The Swietenia macrophylla King (Meliaceae) mahogany tree is widely spread in the neotropics. In Ecuador, it has a wide distribution range from the coastal zone to the Amazon. The mahogany tree is an endangered species due the overexploitation of the high commercial value of its wood. This study is aimed to characterize the Simple Sequence Repeat (SSR) variability of 123 trees selected from six provinces of Ecuador. The results showed that the natural mahogany population had a low level of genetic diversity (A = 6.9; Ho = 0.39; He = 0.43) and a significant heterozygous deficit inbreeding coefficient (F = 0.16). The probability of identity (PI) of the 12 microsatellite markers was low 4.3 × 10−9 and the cumulative exclusion probability of 99.99%. Additionally, the relatedness coefficient among individuals was −0.010 (se = 0.004). The genetic diversity among populations was moderate (ΦST = 8%). In addition, the structure analysis showed two genetic groups; however, it was possible to distinguish admixture within the entire range evaluated. These results show the need to establish strategies that allow the recovery and increase of the genetic diversity in natural populations, especially with the selection of trees to harvest seeds, as well as crossing the tree genetic pool to recombine their diversity.
The genetic characterization of fall armyworm populations in Ecuador and its implications to migration and pest management in the northern regions of South America Rodney N. Nagoshi, Ernesto Cañarte, Bernardo Navarrete, Jimmy Pico, Catalina Bravo, Myriam Arias de López, Sandra Garcés-Carrera Plos One, 2020 The fall armyworm (Spodoptera frugiperda) is a moth pest native to the Western Hemisphere that has recently become a global problem, invading Africa, Asia, and Australia. The species has a broad host range, long-distance migration capability, and a propensity for the generation of pesticide resistance traits that make it a formidable invasive threat and a difficult pest to control. While fall armyworm migration has been extensively studied in North America, where annual migrations of thousands of kilometers are the norm, migration patterns in South America are less understood. As a first step to address this issue we have been genetically characterizing fall armyworm populations in Ecuador, a country in the northern portion of South America that has not been extensively surveyed for this pest. These studies confirm and extend past findings indicating similarities in the fall armyworm populations from Ecuador, Trinidad-Tobago, Peru, and Bolivia that suggest substantial migratory interactions. Specifically, we found that populations throughout Ecuador are genetically homogeneous, indicating that the Andes mountain range is not a long-term barrier to fall armyworm migration. Quantification of genetic variation in an intron sequence describe patterns of similarity between fall armyworm from different locations in South America with implications for how migration might be occurring. In addition, we unexpectedly found these observations only apply to one subset of fall armyworm (the C-strain), as the other group (R-strain) was not present in Ecuador. The results suggest differences in migration behavior between fall armyworm groups in South America that appear to be related to differences in host plant preferences.
Agro-morphological characterization “in situ” of tamarindus indica L. In the dry forest of Ecuador Pertanika Journal of Tropical Agricultural Science, 2019
Development of a new maize hybrid for the ecuadorian lowland Ricardo Limongi-Andrade, Daniel Alarcón-Cobeña, Eddie Zambrano-Zambrano, Marlon Caicedo, Paúl Villavicencio-Linzan, José Eguez, Bernardo Navarrete, Carlos Yanez, José L. Zambrano Agronomia Colombiana, 2018
