Tesis Agronomía

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Actividad insecticida de tres extractos etanólicos de plantas sobre pulgón negro en el cultivo de haba (Vicia faba)
(2025-08) Aynaguano Quicintuña, Martha Cecilia; Zurita Vásquez, José Hernán
This research was conducted with the purpose of evaluating the insecticidal activity of three ethanolic plant extracts on the black aphid (Aphis fabae) in the broad bean crop (Vicia faba). The study took place on the property of Mr. Manuel Aynaguano, located in the San Juan sector, Juan Benigno Vela parish, Ambato cantón, Tungurahua province. A Completely Randomized Block Design (CRBD) was used with a factorial arrangement of 3 extracts × 2 doses × 2 frequencies + 1 control (3×2×2+1), with three replications. Evaluations carried out at 7, 14, 21, and 28 days after application revealed that the ethanolic plant extracts are highly effective in controlling the black aphid (Aphis fabae). A progressive and significant reduction was observed in both the infestation percentage and the number of aphids per plant across all treatments. The extracts of Cinchona (E3-D1-F1) and Tagetes (E2-D1-F1) achieved an efficiency greater than 90%, reducing infestation to less than 50% by day 28, in contrast to the control treatment which reached 100% infestation and an average of 24.03 aphids per plant. The 7 day application frequency proved to be the most optimal, maximizing pest control. In addition to pest control, the most effective treatments also favored the vegetative development of the broad bean crop. A moderate increase in plant height was observed, with E2-D1-F1 reaching 35.67 cm, surpassing the control (29.3 cm)
Adaptación de diez genotipos de zanahoria (Daucus carota) para zonas de altura en Quero - Tungurahua
(2022-09) Pallo Martínez, Klever Daniel; Guerrero Cando, David Aníbal
The importance of carrot cultivation (Daucus carota) at the national level is part of the food group with the most benefits for human beings, it is consumed directly or made into drinks, the value of this root lies in its nutritional importance; the adaptability of more carrot genotypes emerges as an alternative for use, new market options, increasing income levels for the producer. The objective of this work was to evaluate the adaptability of ten carrot genotypes (Daucus carota) together with two controls, for high altitude areas in Quero-Tungurahua, estimating their adaptation and agronomic behavior, as well as determining the yield per treatment studied. The trial was carried out in the Jaloa El Rosario community of the Quero canton, province of Tungurahua. According to the Global Positioning System (GPS) it is located at an altitude of 3,320 meters above sea level with its geographic coordinates of 1°25'41" South latitude and 78°34'44" West latitude. A DBCA randomized block design was used, with ten treatments, two controls and three replications. The data obtained from the trial were analyzed using the Infostat statistical package, applying an ADEVA, a 5% Tukey test was used for significant values, the results obtained show that T4 (Chantenay EMC559), presented the best characteristics, agronomic and of yield, being an alternative for the locality, the opposite happened with the T10 that was not adapted to the conditions of the study locality, concluding that the Genotype T4 (Chantenay EMC559) is an alternative for the small and large producers of the highlands.of Quero.
Adaptación de tres híbridos de tomate hortícola (Lycopersicum esculentum) bajo cubierta plástica
(2023-09) Tubón Tite, Wendy Lizbeth; Curay Quispe, Segundo Euclides
The research focuses on the behavior of three horticultural tomato hybrids (Lycopersicum esculentum) under plastic cover. A completely randomized block experimental design (DBCA) was used with 3 treatments and a commercial control and 4 repetitions. Several variables were evaluated, such as survival percentage, plant height, stem diameter, number of days to flowering, number of days to fruiting, number of days to harvest, number of fruits, distance between clusters, equatorial diameter. , polar diameter and fruit weight. For the statistical analysis of the data, the SPSS Statistics program was used and tests such as Scheffe were applied with a significance of 0.05; Homogeneity of variances with a confidence level of 95%. Showing that the three horticultural tomato hybrids successfully adapted under plastic cover in the Huachi Grande parish, Ambato canton, Tungurahua province. Where it was observed that the H1-Arsin Hybrid showed outstanding results in the variables studied during the investigation, as the third best in survival with 94.28%, greater stem diameter at 75 days with 1.41 cm, fewer days of flowering with 42.55 days, fewer days of fruiting with 57.70 days, greater polar diameter with 6.26 cm and higher yield (20,100 kg/ha), the shape of the fruit was round, which indicates a favorable fruit production in this variety and adapted to the environmental conditions of the Huachi Grande parish, which makes it the most promising option in the study.
Aislamiento de microorganismos benéficos asociados en plantas sanas de fresa (Fragaria x Ananassa) en la comunidad Angahuana Bajo
(2025-02) Iza Bravo Liliana Patricia; Pomboza Tamaquiza Pedro Pablo
The present study carried out on the isolation of associated beneficial microorganisms in healthy strawberry plants (Fraggaria ananassa). Soil samples were obtained from strawberry crops located in the Angahuana Bajo community, Santa Rosa Parish. It was obtained from 8 plants from two plots. Culture media were prepared and the microorganisms were inoculated in each Petri dish. The plates were then analyzed with the help of a microscope and information on colony formation was recorded. The developed fungi were isolated and performed by microculture to obtain pure cultures. These samples were identified and morphological characterization was carried out. The number of hyphae, conidia, conidiophores and number of spores were counted. The front and back color of each mushroom was recorded. The main results obtained were the isolation of 5 fungi which were identified and characterized. Within the study carried out, 4 species of pathogenic fungi and one beneficial fungus were found. In the rhizosphere soil, the genus Fusarium sp and the genus Penicillium sp were the most frequently colonized by pathogenic fungi; the genus Brachysporium sp and Cladosporium sp were less frequently colonized, and the beneficial fungus was found to be the genus Trichoderma sp. The beneficial fungus helps to improve the access and absorption of nutrients, such as the decomposition of organic matter. In addition, it helps to protect phytopathogenic fungi, which are related to crops.
Aislamiento y caracterización del agente causal de pudrición en el cultivo de Allium fistulosum L
(2025-08) Arcos Carrillo, Darwin Wilfrido; Veloz Naranjo, Walter Oswaldo
Onion (Allium fistulosum L.) is one of the crops of great economic and culinary importance in various regions of the country, particularly in provinces such as Tungurahua, Cotopaxi, and Chimborazo. However, its productivity is negatively affected by the presence of diseases, with stem rot being one of the most common and damaging, leading to significant losses for farmers who are often unaware of the specific cause of the problem and, therefore, unable to implement effective solutions. For this reason, the objective of this research was to isolate and characterize the causal agents of stem rot in onion crops in the community of San Pedro de Sabañag, located in the Quero canton, province of Tungurahua. The methodology involved collecting samples from two study areas, three from each, followed by isolation using selective culture media. Microscopic and macroscopic evaluations were then conducted, which allowed for the identification of Fusarium oxysporum and Sclerotium cepivorum Berk. as the primary pathogens responsible for the rot. These pathogens are considered a significant threat to crop stability and to the economic well-being of local farmers; thus, it is recommended to develop specific strategies aimed at effective disease management and control.
Aislamiento y caracterización del agente causal de pudriciones en el cultivo de Allium sativum L.
(2023-09) Tituaña Cajahuishca, Mónica Tatiana; Guerrero Cando, David Aníbal
Garlic (Allium sativum L.) is one of the crops with the smallest planting area in Ecuador due to its phytosanitary problems and the lack of quality seed bulbs. One of the factors that affects the production of this crop is the presence of diseases, among the most common is bulb rot. For this reason, the present investigation was proposed with the objective of identifying the causal agents that occur in the rotting of the garlic crop in the Pilahuín parish belonging to the Tungurahua province. Three isolates were obtained from infected bulb tissue, which were selected for cultural and morphological characterization. The results indicated that the causative agents of the most common rots were Fusarium oxysporum f.sp. cepae, Penicillium allii and Sclerotium cepivorum Berk. It is hoped that the results of these studies serve as a basis for the establishment of an integrated disease management program that leads to an increase in the garlic (Allium sativum L.) planting area in order to reach a supply in Ecuador.
Aplicación de calcio boro zinc en el cultivo de mora (Rubus glaucus Benth) y su influencia en la calidad y productividad
(2026-01) Carranza Panata, Alejandra Elizabeth; Veloz Naranjo, Walter Oswaldo
The objective of this research was to evaluate the influence of calcium, boron, and zinc application on the quality and productivity of blackberry crops. A field trial was conducted in the Mocha canton, Yanahurco community, Tungurahua province, using a previously established 3-year-old plantation. Foliar applications of two Ca-B-Zn sources (Nektar Ca-B-Zn and Complex Ca-B-Zn) were carried out. The study followed a completely randomized block design with a 2×3+1 factorial arrangement. Experimental data were analyzed using the Infostat statistical software, employing analysis of variance (ANOVA) and Tukey’s test at a 5% significance level. The evaluated variables included number of flowers per branch, number of fruits per branch, fruit weight, number of fruits, and yield. The results showed that the use of these nutrients, according to product and dosage, significantly influenced yield, with Nektar Ca-B-Zn at a dose of 250 cc standing out as the most efficient alternative, as it recorded the highest yield (14.62 g/crop) compared to the other treatments. It is recommended to maintain a standard application dose (250 cc) during stages of highnutritional demand to prevent deficiencies that could affect crop development and productivity .
Aplicación de complejo nutri-hormonal en el cultivo de aguacate (Persea americana) mediante endoterapia vegetal
(2026-01) Llerena Sarabia, Mario José; Zurita Vásquez, José Hernán
The present study evaluated the application of a nutri-hormonal complex in avocado (Persea americana) cultivation through the technique of plant endotherapy, with the purpose of determining the optimal dosage and volume to stimulate a physiological response in the crop. The research was carried out in the Patate canton, belonging to the province of Tungurahua, in the San Rafael area, under a randomized complete block design (RCBD) consisting of 7 treatments: one control and six combinations derived from two doses of the complex (0.5 and 1.0 cc/L) and three application volumes (50, 100, and 150 mL). The evaluated variables included chlorophyll content (SPAD), foliar nitrogen concentration, moisture percentage, leaf coloration, and sprouting percentage at 30 and 60 days after application (DAA). The results showed marked variations among treatments, revealing that the 1.0 cc/L doce combined with a 100 mL volume generated the best physiological response: notable increases in chlorophyll content, higher nitrogen concentration, and a higher sprouting percentage. Likewise, the treatments that received a greater nutrient supply presented a more intense leaf coloration associated with a more favorable nutritional status. Overall, considering all the data, it is observed that the endotherapy method proves to be an efficient, precise, and highly absorbent technique for the nutri- hormonal solution in avocado, representing a viable alternative to optimize vegetative vigor and enhance the physiological functioning of the crop under real field conditions.
Aplicación de enraizantes naturales en la propagación vegetativa de la uva (Vitis vinífera) por medio de esquejes
(2023-09) Sigcha Azogue, Mercy Nataly; Velástegui Espín, Giovanny Patricio
In Ecuador the cultivation of the vine (Vitis vinifera) began with the arrival of the Spaniards to America and was distributed in various Andean areas, so this research work was conducted in the Tambillo parish, the purpose of this research was to generate information on the methods of propagation of the vine, using natural extracts to promote the propagation of this fruit. The important factors in the propagation of the vine are the rooting agents that help the proliferation and formation of a good root system, giving way to the formation of a new plant; The objective of this research work was to compare the efficiency of natural rooting extracted from lentil, willow and wheat in the propagation of grape (Vitis vinifera) by means of cuttings, where the variables evaluated were survival or rooting percentage, root number, root length, root system volume and number of shoots; a completely randomized design with a bifactorial analysis, with three replications, was used in the field work. Prior to the statistical analysis, the data transformation was done with √(x+1), and then using the Tukey test at 5%, the data collection was done from 30 days to 90 days, where the study factor was E1 (adult grape cutting) and E2 (young grape cutting); followed by the extract factor P1 (lentil extract), P2 (willow extract), P3 (wheat extract), and finally the commercial rooting agent Radifit applied on adult and young cuttings; from these parameters it could be established that the rooting agent Radifit in T1 (Radifit adult cuttings) and T2 (Radifit young cuttings) obtained significant differences at 1% by obtaining a p-value of 0.0001% in most of the variables. In addition, a cost analysis was performed between the natural and commercial rooting agents, where the natural rooting agents had a total cost of US$ 8.40 and the commercial rooting agent had a total cost of US$ 10.
Aplicación de etileno como inductor de la floración en el cultivo de zapallo amarillo (Cucúrbita pepo)
(2025-08) Villacrés Altamirano, María de los Ángeles; Zurita Vásquez, José Hernán
This study addresses the issue of low yield in yellow squash (Cucúrbita pepo) cultivation, mainly caused by an imbalance between male and female flowers, which limits reproductive efficiency and consequently fruit production; therefore, the objective was to evaluate the effect of ethylene application as a plant growth regulator to induce female flowering and improve fruit set. To this end, an experiment was carried out using a completely randomized block design with a 3×3 + 1 factorial arrangement (control), considering three ethylene doses (2.5, 5, and 7.5 cc/L/L) and three application times (60,70, and 80 days after transplanting), with three replications per treatment. The variables evaluated were days to flowering, total number of flowers, male flowers, female flowers, and fruit set. The results showed that although ethylene did not significantly affect the days to flowering, it did promote a reduction in male flowers and a significant increase in female flowers and fruit set, with the effect being most notable when applied at 60 days after transplanting, where the 7.5 cc/L dose resulted in the highest number of female flowers (82) and fruit set (37); at 70 and 80 days, the positive effect was maintained but to a lesser extent, especially with higher doses. In conclusion, Ethephon demonstrated a dose-dependent efficacy in promoting female flowering and reproductive yield in yellow squash, with the 7.5 cc/L application at 60 days after transplanting being the most effective combination for maximizing crop productivity
Aplicación de extracto de ajo ozonizado para el control de paratrioza (Bactericera cockerelli) en el cultivo de papa (Solanum tuberosum) en el Cantón Mocha
(Universidad Técnica de Ambato Carrera de Agronomia, 2026-07) Freire Bonilla, Edith Scarlet; Zurita Vásquez, José Hernán
Potato cultivation (Solanum tuberosum) is a fundamental socioeconomic pillar for food security in the Ecuadorian Andean region; however, its productivity faces critical challenges due to the psyllid Bactericera cockerelli, the vector of the phytoplasma responsible for "purple top" disease, which can cause yield losses of nearly 100%. Given the urgent need to reduce reliance on synthetic agrochemicals, this research— framed within the line of sustainable phytosanitary management—evaluated the efficacy of ozonated garlic extract in controlling this pest in the Mocha Canton. A Randomized Complete Block Design (RCBD) with a factorial arrangement (2x2+1) was used, comparing doses of 2.5 cc/L and 5 cc/L against application frequencies of 8 and 15 days. The incidence of eggs, nymphs, the presence of phytoplasma in tubers, and total yield were quantified. The scientific novelty lies in the application of ozonolysis to stabilize the secondary metabolites of garlic, forming highly reactive ozonides that enhance its insecticidal and repellent action against sedentary stages of B. cockerelli. Results indicated that the most effective treatment was D1F1 (2.5 cc/L every 8 days), followed by D2F2. Compared to the control group, these treatments showed a lower population incidence and greater crop stability, establishing that the application of 2.5 cc/L every 8 days constitutes the most efficient technical strategy under local conditions. This proposal confirms that the ozonation of plant extracts optimizes phytosanitary control, offering an innovative, economically viable, and environmentally responsible solution that guarantees tuber quality in the face of pesticide pressure.
Aplicación de la Electrocultura en el cultivo de Lechuga (Lactuca sativa)
(2024-08) García Hernández, Santiago Giovanni; Zurita Vásquez, José Hernán
The present investigation was carried out on the premises of the Unamuncho sector of the Ambato canton, province of Tungurahua, with the purpose of applying Electroculture in Lettuce (Lactuca sativa), using antennas made manually with copper wire material and galvanized aluminum wire. . A randomized complete block design was carried out with five treatments in three repetitions. To record data, they were obtained using a DBCA and with the Tukey test at 5%, observing the following variables: Height of the plant at the time of harvest (cm), chlorophyll and nitrogen content, days to harvest, weight of cabbage at harvest, diameter of cabbage at harvest, electrical conductivity of the soil, recording the following results: The treatments carried out in the research project M1A1, M1A2 (copper wire) and M2A1, M2A1 (galvanized aluminum wire) They are very effective compared to the Witness who has had a poor performance. In plant height, the treatment that stood out the most was M1A2, with a height of 18.04 cm; In the weight of cabbage, the treatment that stood out the most was M1A2, with a weight of 1341.67 g; In the diameter of the cabbage at harvest, the treatment that stood out was M1A2, with a diameter of 19.13 cm; In the chlorophyll content, it was found that the M1A1 treatment, with an average of 24.95, was the one that stands out the most of all the treatments and the control; In the nitrogen content, M1A1 stood out the most, with an average of 8.03; With respect to the electrical conductivity of the soil, it was obtained that treatments M1A1 and M1A2 have an average of 30.28, treatments M2A1 and M2A2 had an average of 32.61 and the Control had an average of 21.14.
Aplicación del método de vernalización en semillas de maíz suave (Zea mays) en la parroquia de Huambaló
(2025-02) Ruiz Paredes Daniela Nagely; Zurita Vásquez José Hernán
Research concerning the application of the vernalization method in corn is scarce, the present document specifies the application of this method as a guide yielding interesting data that could change the production matrix of this species when applied in a simple way. The experiment was developed in the Huambaló parish with the objective of evaluating the effects of this method on the germination, flowering and development of the corn crop in a region with specific climatic characteristics. Using a completely randomized block design with 2 x 2 + 1 factorial arrangement, treatments were carried out with combined temperatures of 3°C and 7°C with exposure times of 120 and 240 hours and compared with a control without vernalization. The results showed that the treatment at 7°C for 240 hours (D2T2) was the most effective, reducing the days to germination, flowering, improving plant uniformity and vigor, with an average germination rate of 91.67%, higher than 79.17% of the control, an average height of 35.25 cm after 25 days and a flowering time of 84 days for male flowering and 90 days for female flowering, respectively. These results demonstrate that vernalization optimizes the maize production cycle and represents a viable technique to improve agricultural yields in the Huambaló parish, where the standard implementation of the D2T2 treatment (7°C - 240hours) is recommended. It is also important to ensure the quality of the seeds and their proper handling before treatment, as well as to promote technical training of farmers to maximize the benefits of this practice and strengthen local agricultural productivity. This study not only contributes to the technical knowledge of maize cultivation but also provides practical tools to address agricultural challenges in the parish.
Bacillus subtilis y calidad del huevo en gallinas en postura tardía: una revisión sistemática
(Universidad Técnica de Ambato Carrera de Medicina Veterinaria, 2026-07) Silva Gaspata, Silvia Maribel; Núñez Torres, Oscar Patricio
Physiological aging in late-phase laying hens affects egg quality and represents a challenge for the sustainability of poultry production. To compile available scientific evidence on the use of Bacillus subtilis as a probiotic to improve egg quality in late-phase laying hens. A quantitative systematic review was conducted using information obtained from scientific articles published between 2018 and 2026 in high-impact databases, following PRISMA criteria and search strategies with Boolean operators. Variables related to egg quality, intestinal morphometry, cecal microbiota, and enzymatic activity were analyzed. The analyzed studies showed increased villus height (1343±1045), reduced crypt depth (206±114), and improved villus height/crypt depth ratio (VH/CD) (6.25±1.89); an increase in beneficial bacteria such as Lactobacillus (28%) and a reduction in pathogenic bacteria (40%) such as E. coli, Clostridium, and Salmonella; as well as improvements in eggshell thickness (0.39±0.0373), shell strength (38.6±0.546), egg weight (62.1±4.98), Haugh units (81.3±10.1), and yolk color (7.42±1.96). Supplementation with B. subtilis constitutes a promising strategy to improve the internal and external
Biología de Oligonychus peruvianus McGregor (Acari Tetranychidae) en dos cultivares aguacate (Persea americana Mill)
(2024-02) Ojeda Barrera, Alex José; Leiva Mora, Michel
The avocado (Persea americana Mill.) is an important fruit tree that is commercially grown in several tropical and subtropical regions. This species is attacked by different species of mites, including Oligonychus peruvianus; however, there are few studies on this topic. According to this, this research aimed to evaluate the bioecological aspects of Oligonychus peruvianus McGregor (Acari Tetranychidae) in avocado (Persea americana Mill). The biology of the mite was studied on two avocado cultivars (Verde and Hass), under laboratory conditions using rearing units. The biological cycle (eggadult) was longer when the females were reared on leaves of cultivar Verde (19.5 days), while in cultivar Hass, this time was reduced by 17.4 % (16.1 days). Females showed greater longevity when they were reared on Hass leaves (20.8 days), while in the Verde, the lifespan was reduced to 12.8 days. Furthermore, fecundity was significantly higher in females reared on Hass leaves (23.8 eggs/female) and decreased to 12.6 eggs/female in females reared on avocado cv. Verde. According to the results, the cultivar Hass seems to offer the best conditions for the development of the mite, therefore, this information should be taken into account when establishing and designing pest management plans. Keywords: avocado, biology, fecundity, longevity, oviposition rate.
Capacidad de depredación de Typhlodromalus sp. y Stigmaeus sp. sobre diferentes estados de desarrollo de Tetranychus urticae (Acari: Tetranychidae) en fresa”
(2024-02) Tercero Gualpa, Elizabeth Mishel; Santana Mayorga, Rita Cumanda
The strawberry (Fragaria X ananassa) is one of the best tasting and most consumed fruits worldwide. In Ecuador, production has begun in the provinces of Pichincha, Tungurahua, Cotopaxi, Chimborazo and others. Strawberry production is affected by several pests, such as thrips, aphids, mealybugs, whiteflies and mites, which attack the crop throughout the year. The mite Zetranychus urticae is considered one of the phytophagous mites worldwide, it causes severe damage in a short time and its reproduction is accelerated, resulting in the decline of large populations of predators such as Typhlodromalus sp. and Stigmaeus sp. generally feed on eriophyid or tetranychid mites, living in the soil and plants. The objective of the trial was to determine the predation capacity of Tiphlodromalus sp. and Stigmaeus sp. on Tetranychus urticae (Acari: Tetranychidae) on strawberry. The research was analyzed by means of an analysis of variance compared by means test according to Tukey (P< 0.05) using the Statistix package and by divided plots. The predators Typhlodromalus sp. and Stigmaeus sp. on different egg densities (5, 10, 20, 30 and 40) and mobile stages, larvae and nymphs, (2, 4, 8 and 16) of 7: urticae were studied in separate trials under laboratory conditions. Through the research carried out, it was possible to calculate the number of prey consumed by the predator Typhlodromalus sp. in egg stages of T- urticae, With the best result being T3 with a density of 20 eggs and an average of 2.8 eggs consumed/day, and for the mobile phase it was determined that the best treatment was T4 with a density of 8 mites reaching an average of 2.12 mites in mobile phase consumed/day. For the predator Stigmaeus sp. in terms of the number of prey consumed in egg stages of T- wrticae it was shown that the most effective treatment was T5 with a density of 40 eggs and an average of 3.6 eggs consumed/day, for the mobile phase it was found that the best treatment was T4 with a density of 16 mites in mobile phases and an average of 1.62 mites in mobile phase consumed/day. Keywords: strawberry cultivation, 7etranychus urticae, depredador, Typhlodromalus sp., Stigmaeus sp.
Caracterización del biochar de mora y su efecto sobre el rendimiento del cultivo de lechuga (Lactuca sativa
(2026-01) Saqui Sailema, Jessica Lissette; Espinoza Vaca, Jorge Santiago
Agricultural systems generate large amounts of plant residues that in many cases are not managed properly and their potential as by-products is lost. In this study, the residues from blackberry pruning were transformed into biochar through pyrolysis and were characterized by determining pH, electrical conductivity and the content of macronutrients (N, P, K, Ca, Mg) and micronutrients (Cu, Fe, Mn, Zn) in order to evaluate their effect on lettuce cultivation under a completely randomized design (CRD) with four treatments: T0 (control), T1 (25 g), T2 (50 g) and T3 (75 g) and ten experimental units established in pots inside a greenhouse. The evaluated variables were number of leaves, plant height, root depth and fresh leaf weight, where statistical differences were observed in most of them, highlighting T1 (25 g) with the highest average weight per plant (217.10 g) and the highest values in number of leaves (18.80), root length (24.20 cm) and the best yield, while plant height did not show significant variation. Overall, these results show that the low dose of blackberry biochar improved the agronomic performance of lettuce, although it is necessary to continue with studies that allow defining its long-term effects on the crop
Conocimiento sobre los métodos de control de plagas agrícolas de los productores de maíz en los cantones Quito y Patate: una comparación
(2024-02) Lesano Yaguar, Kevin Javier; Vásquez Freytez, Carlos Luis
Maize crop (Zea mays L.) has spread rapidly throughout the world and has become one of the main cereal crops worldwide. As in other important crops, the use of agrochemicals is the main method of pest control, however, little is known about the level of farmers' knowledge about the risk of this type of strategy. In this sense, this research aimed to diagnose the knowledge of agricultural pest control methods of corn farmers in the Quito and Patate cantons. A structured survey was applied to a sample of 40 respondents in each study area. Among the main pests in both areas represented by the fall armyworm (Spodoptera frugperda), cutworm (Agrotis spp.), slugs and aphids, chemical control being used as the main pest management method. According to the results, producers in both areas are unaware of or do not give importance to the risks associated with the excessive use of pesticides, such as problems to human, animal, soil and water health. In relation to the factors that determine this behavior, it is included that farmers consider that they are effective products for pest control and that, for Patate producers, they show a rapid effect in control. Finally, the almost total lack of knowledge on the part of farmers about the potential benefit of other strategies such as biological control, use of resistant varieties, among others, was confirmed. The design of training and awareness campaigns for corn producers is recommended to avoid damage to health and the environment. Keywords: pest control, sustainable strategies, corn, Patate, Quito
Desarrollo de técnicas de detección de Fusarium oxysporum f. sp. cubense raza 4 (R4T) utilizando tres pares de primer a través de (PCR) tiempo final
(2024-08) Chasi Oyasa, Xiomara Monserrath; Leiva Mora, Michel
Fusarium oxysporum f. sp. cubense race 4 (R4T) is a pathogen that specifically affects Musaceae. This phytopathogenic agent causes the most devastating diseases of these crops worldwide. Attacking several cultivars belonging to the Cavendish subgroup (AAA), they are seriously affected by race 4, which currently represents the majority of world production and export. The objective of this research was to “Develop detection techniques for Fusarium oxysporum f. sp. cubense race 4 (R4T) using three pairs of primer through end-time (PCR). To comply with this, the biomass is lyophilized, the DNA was extracted with the use of buffers (Buffer A NaOH + Tween 20 and Buffer B Tris HCl + EDTA). It was subsequently centrifuged and cleaned with absolute ethanol, and stored at -20°C. For amplification using conventional PCR, different programs were established according to the primer sets used. 4 µl of the Mastermix solution was used for each reaction, sets of primers (Forward-reverse), ultrapure water, to complete a final reaction volume of 54 µl. For visualization of the gels, 1.5% agarose was used with the following sets of primer W2987-F; W2987-R and FocTR4-F; FocTR4-R and 1% agarose with the primer EF1 and EF2 and the 1X TAE running buffer, using 2 µl of the SYBR safe intercalating agent to be able to observe the Invitrogen DNA bands. Finally, molecular markers (Tracklt TM 50bp and 100 bp Invitrogen) were used to determine the size of the bands. The results were the presence of a DNA band with the first W2987-F; W2987-R and FocTR4-F; FocTR4-R, the molecular weight marker (Tracklt TM 50bp Invitrogen) was used at 1.5% agarose, at a hybridization temperature (annealing) of 60 °C, bands of approximately 452 and 463 were visualized, with the primer EF1 and EF2. R the molecular marker (Tracklt TM 100bp Invitrogen) was used in 1% agarose, at a hybridization temperature (annealing) of 60 °C a band of approximately 700bp was visualized.
Detección de genes Avr y Ecp en aislados de Cladosporium fulvum Cooke en tomate de riñón del cantón Patate
(2025-08) Saquinga Galora, Danny Javier; Leiva Mora, Michel
The study involved the extraction and molecular analysis of genomic DNA fromC. fulvum isolates from the Patate canton, obtaining high-quality genetic material suitable for PCR. The presence of avirulence genes (Avr) and extracellular proteins (Ecp) was investigated, as these are key elements in the interaction between the pathogen and tomato (S. lycopersicum) and in the virulence of the fungus. The results indicated that the Avr2 gene was not present in all isolates, demonstrating its loss in the studied population. In contrast, the Avr4 and Avr9 genes were detected in 50% of the isolates, and Avr4E in only 30%, evidencing genetic variability even among isolates from the same locality. On the other hand, the Ecp1 gene was successfully amplified in all samples, while the Ecp2 and Ecp4 genes were amplified in 40% and the Ecp 5 gene was only found in 20%, confirming their expression and relevance in the pathogenic process. The specificity and reliability of the amplifications were validated by negative and positive controls included in the assays. These findings underscore the need to monitor the genetic diversity of C. fulvum to develop integrated management strategies, including the selection of resistant varieties and appropriate agricultural practices. In addition, the study of Avr and Ecp genes provides new insights into the molecular mechanisms used by C. fulvum to evade the defensive response of tomato crops. These results allow genetic breeders to suggest the Cf resistance genes that need to be introduced into the tomato genotypes to be grown in the Patate canton