Ingeniero Agronomo

Permanent URI for this collection

http://repositorio.utm.edu.ec/handle/123456789/819

Browse

Browsing Ingeniero Agronomo by Author "" ""
  • Item
    Actividad biológica de aceites vegetales sobre estadios larvales de Spodoptera frugiperda en condiciones de laboratorio y casa de vegetación en el cultivo de maíz
    (Ingenieria Agronomica, 2024) Castro Mendoza, Julissa Jamileth ; Cusme Vera, Lilibeth Cecilia ; " " ; " "
    Maize is one of the main cereals grown in all regions of Ecuador as part of the food sovereignty and security of the people. In the Ecuadorian coastal region, where corn is produced on large extensions, one of the main problems is the attack of the fall armyworm (Spodoptera frugiperda), which causes damage to the plant from its early days of development. Consequently, applications of chemical insecticides are a frequent activity. The biological activity of vegetable oils was determined in larvae of S. frugiperda under laboratory and greenhouse conditions in corn cultivation, aiming to achieve highly sustainable and profitable agriculture. The research was conducted at the National Department of Plant Protection (DNPV), Portoviejo Experimental Station of the National Institute of Agricultural Research (INIAP). Four concentrations (2.0%, 3.0%, 4.0%, and 5.0%) were studied using two types of vegetable oils (castor [Ricinus communis L., Euphorbiaceae] and physic nut [Jatropha curcas L., Euphorbiaceae]), with a control (water) and a test oil (NEEM-X® - neem 2%), under laboratory and greenhouse conditions. The trials with physic nut and castor oils in the laboratory were conducted separately, using a DCA with six biological replicates and the non-parametric Kruskal-Wallis test (P<0.05). In the laboratory trials, the variables evaluated were leaf consumption, number of live and dead larvae. In the greenhouse trial, visual damage, weight (g), and height (cm) of the plant were evaluated. In the control, greater leaf consumption and higher percentages of S. frugiperda pupae and adults were observed. With the 4% castor treatment, S. frugiperda larvae showed the lowest leaf consumption at 0.6%. Higher larval mortalities were observed with different doses of castor and physic nut extracts. In the survival percentage of pupae and adults, lower values were observed with higuerilla, neem, and physic nut oil treatments at 4% and 5%. It is noteworthy that the treatment with 4% castor extract resulted in the longest larval-adult stage period. In the greenhouse experiment, plants treated with 2% castor oil showed the greatest height (13.6 cm), while control plants (12 cm) and those treated with 3% physic nut (9.6 cm) registered the lowest values. Physic nut and castor extracts showed effectiveness at the different doses used for the control of S. frugiperda larvae.
  • Item
    Ajuste poblacional en el cultivo de maíz (Zea mays L) bajo distintos sistemas de siembra
    (Ingenieria Agronomica, 2023) Macías Loor, María Alexandra ; Zambrano Castro, Luis Angel ; " " ; " "
    In Ecuador there are 322,846 hectares dedicated to planting corn, with a production of 1,479,770 t/m annually. While in the province of Manabí there are 95,519 ha, with a production of 267,946 t/m per year. The objective of this work was to evaluate the population effect on corn cultivation under different planting systems and the number of seeds per planting site. The experiment was conducted at the facilities of the Faculty of Agronomic Engineering of the Technical University of Manabí, located in the Lodana parish km 13½ via Portoviejo-Santa Ana. 16 treatments were evaluated based on the combination of the levels of Factor A: system of sowing (single and double row), Factor B: sowing densities (57,000, 73,000, 95,000 and 140,000 plants ha-1) and Factor C: number of seeds per sowing site (one and two seeds per site). Measurements were made such as plant height, stem diameter, chlorophyll index, leaf area index, grain weight, number of grains and production. A completely randomized block design was used with an arrangement of subdivided plots and an analysis of variance was performed at 5%. Among the main results, it stands out that production was favored based on the higher planting density evaluated, increasing production by more than 200%. In addition, the use of a single row planting system favors morphological aspects such as greater stem diameter of the plant. plant among others. It is concluded that it is essential to increase super seeding populations based on the growth characteristics of commercial corn hybrids in Ecuador.
  • Item
    Aplicación de aceites vegetales en el control del gusano cogollero (Spodoptera frugiperda J.E. Smith) en dos ciclos productivos de maíz (Zea mays L.)
    (Ingenieria Agronomica, 2023) Bravo Macías, Erick Ronaldo ; García Loor, Gregory José ; " " ; " "
    This study aimed to assess the efficacy of piñon oil (Jatropha curcas) and castor oil (Ricinus communis) vegetable oils in controlling fall armyworm (Spodoptera frugiperda) in maize crops during two production cycles. A randomized complete block design consisting of 40 experimental plots, ten treatments, and four replications was employed. Four concentrations of the oils, along with a chemical control (Lorsban) and an absolute control (water only), were tested. The results demonstrated the effectiveness of both vegetable oils in reducing fall armyworm infestation. However, their efficacy varied depending on the season. Jatropha oil exhibited greater effectiveness during the rainy season, while Ricinus oil showed better results in the dry season. It is important to note that both oils displayed some phytotoxicity in the maize crop, although without significant impact on yield. These findings underscore the potential of vegetable oils as environmentally friendly and efficient alternatives for pest control in maize cultivation. Their utilization can be particularly advantageous for small-scale farmers and in developing countries, given their ecological benefits compared to chemical insecticides. Nonetheless, caution should be exercised regarding phytotoxicity, and application should be adjusted accordingly based on seasonal variations. This study contributes valuable insights to integrated pest management practices and emphasizes the significance of seeking sustainable approaches for safeguarding crop productivity.
  • Item
    Aplicación de láminas de riego y utilización de giberelina en la producción de limón sutil [Citrus aurantifolia (Christm.) Swingle]
    (Ingenieria Agronomica, 2023) Pincay Sánchez, Lady Diana ; Pincay Sánchez, Lady Laura ; " " ; " "
    Currently, lemon production is often threatened by the effects of climate change, with drought being the main problem, which is why producers are forced to meet the water demands of the crop, however, it is of the utmost importance. seek to save water without affecting the productivity of the crop, therefore, a moderate reduction of water is convenient, with 50% of the ETC. Gibberellins also play an important role as a regulator of plant growth and especially in fruit set, they have been involved in different physiological processes and improve the production and quality of the fruit, being considered a highly profitable alternative for the producer. The purpose of this research was to determine irrigation sheets and the application of gibberellins in the production of subtle lemon (Citrus aurantifolia Swingle). The trial was carried out in the Santa Ana Canton, Manabí province. Three irrigation sheets (51,72 m3 h-1; 46,55 m3 h-1; 38,79 m3 h-1) and two doses of gibberellic acid (80 ppm and 200 ppm) were applied to the subtle lemon crop. Among the yield variables, fruit growth, fruit weight, equatorial and polar diameter were evaluated, while the internal quality variables of the fruit that were evaluated were pulp weight, shell weight, juice content, number of seeds and fruit content. of soluble solids “brix degrees”. As results, it was obtained that the highest growth rates of the fruit (45,40 g) and yields (49,47 kg/tree) were reached with water volumes of 51,72 m3 h-1 corresponding to sheet. While that the doses of GA3 did not differ significantly in any of the variables of growth and internal quality of the fruit. Therefore, it is concluded that the effect of the irrigation sheets was more present than the hormonal effect.
  • Item
    Artrópodos asociados a diferentes genotipos de cacao (Theobroma cacao L.)
    (Ingenieria Agronomica, 2023) Barcia Rodríguez, Carlos Emilio ; " " ; " "
    Cacao (Theobroma cacao L.) is a crop in great demand, since the beans are used to produce chocolate, which presents various characteristics both in flavor and in health benefits. Ecuador is a producer and exporter of cocoa, so the management of the crop is intensified and causes the loss of biodiversity. The main objective of this research was to identify the arthropods associated with different cacao genotypes. The study was carried out in a 2800 m2 plot of cocoa designed in random blocks with three repetitions located at the Faculty of Agricultural Engineering, Technical University of Manabí. In the lot there are 24 cacao materials, including the national type and the CCN-51, of which four combinations (pattern/graft) were chosen (EET-339/EET576, IMC-67/EET484, EET-400/EETP- 800 and POUND-12/CCN-51), each combination had four cacao plants planted. Leaf samples were taken to identify populations of aphids (Toxoptera aurantii) and mealybugs (Dysmicoccus sp.). Yellow traps were also placed to identify the number of individuals per family of phytophagous insects, parasitoids and predators. Alcohol traps were used to identify scolytines taxa and ear evaluation in the field was performed to establish ear damage by bugs of the genus Monalonion. Four taxa of scolytines Hypothenemus sp., Xyleborus affinis, Premnobius sp., Corthylus sp. On the leaves, Toxoptera aurantii was significantly higher than the EET-399/EET-576 genotype and the number of mealybugs of the genus Dysmicoccus was low and did not differ between genotypes. In the traps, the most abundant phytophagous families were Chrysomelidae and Membracidae. For natural enemies, important families of predators such as Coccinellidae, Dolichipodidae and Vespidae were observed. Six families of parasitoids were present associated with cacao genotypes. The EET-400/EETP-800 genotype exhibited the highest number of ears damaged by bugs of the genus Monalonium, reaching 25% damage, and the highest damage scale with grade 3 was also observed. These results represent a significant contribution to the knowledge of the entomofauna associated with cocoa that until now has been little studied in Ecuador. It is suggested that future studies focus on measuring the effects that scolitins can cause in cacao, and the role played by the families of predators and parasitoids found.
  • Item
    BACTERIAS PROMOTORAS DE CRECIMIENTO EN EL FRÉJOL AUPÍ(Vigna unguiculata L.WALP.)
    (Ingenieria Agronomica, 2023) Palma Velásquez, Abrahán Alfredo ; " " ; " "
    Cowpea bean (Vigna unguiculata L. Walp.) has traditionally been an important crop for 18 smallholder farmers, and in many cases is the main source of low-cost dietary plant 19 protein and minerals compared to animal products such as meat, fish, and egg. The 20 inoculation of rhizobia in cowpeas is a promising technology to improve production. In 21 this work, the importance of growth-promoting bacteria in cowpea beans was evaluated 22 through a literature review, in order to improve the performance of the production 23 system in the different stages of the crop. A search of bibliographic information has 24 been carried out for the preparation of this literature review using scientific information 25 published from 1982 to the present, totaling 67 documents (books, book chapters, 26 scientific articles, among others) written in different languages such as Spanish, English 27 and Portuguese, included in the SCOPUS, Web of Science, Scielo, Redalyc and 28 Latindex 2.0 platforms. The keywords ¨Cowpea beans¨, ¨Origin of cowpea beans¨, 29 ¨Distribution of cowpea beans¨, ¨Phenological cycle of cowpea beans¨, ¨Botanical 30 description of cowpea beans¨, ¨Nutritional requirements of cowpea beans¨, ¨Plant 31 growth promoting rhizobacteria¨, ¨Nitrogen fixing bacteria¨ and ¨Growth promoting 32 bacteria in cowpea¨. The Mendeley program was used as a bibliographic manager. The 33 importance of the promoter bacteria in the cowpea bean crop was demonstrated, in all 34 the searches carried out, the bacteria belonging to the genus Bradyrhizobium 35 predominating as the most used in this crop.
  • Item
    Balance energético en el cultivo de pitahaya (Hylocereus undatus (Haw.) Britton y Rose) en dos localidades de la zona sur de Manabí
    (Ingenieria Agronomica, 2024) Moreira Delgado, Laura Jazmín ; Mendoza Valdez, Wilson Israel ; " " ; " "
    The energy balance is essential for analyzing energy inputs and outputs in agriculture, which provides valuable information for evaluating the ecological sustainability of production. The objective was to calculate the energy balance in the production cycle of pitahaya (Hylocereus undatus (Haw.) Britton and Rose) in southern Manabí, Two farms were evaluated: La Abundancia (LA, Santa Ana) and Santa Rosa (SR, May 24). To determine the direct (fuel, labor) and indirect (seeds, fertilizers, insecticides, machinery) input and output (harvested biomass) energy parameters, field data sheets and structured interviews with farm managers were used. For the analysis of energy inputs and outputs, descriptive statistics were used through flow diagrams using Microsoft Visio 2023 software. For the energy input and output parameters, equations were used, which were calculated and analyzed using Excel spreadsheets. In both farms nine activities related to pitahaya management were identified; for (LA, Santa Ana) ten input parameters and one output parameter were recorded, while in (SR, 24 May) 11 input parameters and one output parameter were identified. The energy input totals showed that (SR, 24 May) had a higher energy expenditure with 329 341.86, compared to (LA, Santa Ana) which presented 205 942.47MJ/ha. In terms of energy expenditure, (LA, Santa Ana), reached a harvested biomass of 3 876,000 MJ/ha, while (SR, 24 May) reached 13 566,000 MJ/ha. The energy balance of the pitahaya crop in both farms reveals a positive situation, where the energy costs associated with the various crop management parameters are lower than the harvested fruit biomass.
  • Item
    Caracterización fenotípica y organoléptica de clones promisorios de Theobroma cacao L. seleccionados en el programa de mejoramiento genético UTM
    (Ingenieria Agronomica, 2024) Loor Macías, Alfonso Alexander ; Zamora Cevallos, María Alejandra ; " " ; " "
    Cacao, native to South America, is a crop of great socioeconomic importance in Ecuador and other countries. This study aimed to evaluate the variability in phenotypic and organoleptic characteristics of nine experimental clones. The study was conducted in an experimental plot located in the canton of Calceta (Manabí, Ecuador). Engels descriptors were used for phenotypic characterization. For organoleptic analysis and sensory profiling, the protocol established by the National Institute of Agricultural Research (INIAP) was used. The evaluated clones have elongated leaves (with a length/width ratio of 3), acuminate apex, and papery texture; the flowers of the nine clones show anthocyanin in the peduncle, petals, and staminodes, with some also presenting it in the sepals and stamen filaments; the fruits are oblong in shape with a weight ranging from 444,5 to 804,5 g. The number of seeds ranged from an average of 37,3 to 46,7, for clones UTM-5103 and UTM-259, respectively, with an average seed/fruit weight of 147±14 g. The cacao liquor from sample UTM 1 stood out for its intense cacao flavor, marked acidity, and prominent notes of fresh fruit and nuts. Sample UTM 2 presented a potent cacao flavor, pronounced acidity, and moderate complexity in its fresh fruit and vegetal notes. Sample UTM 3 showed a strong cacao flavor with highlighted acidity, more evident brown fruit and nut notes, with a balance between bitterness and astringency. In conclusion, the data analysis shows notable variability in the floral, leaf, and fruit characteristics among the clones, indicating significant genetic diversity. The organoleptic profile of the seeds allowed for the identification of sensory differences between the evaluated materials, facilitating the selection of those with ideal characteristics for specific markets.
  • Item
    Caracterización fenotípica y reproductiva de genotipos promisorios de Theobroma cacao
    (Ingenieria Agronomica, 2024) Pico Sornoza, Diego Armando ; Santana Mantuano, Gema Elizabeth ; " " ; " "
    Cocoa is a species native to the tropical forests of South America, considered one of the world's most important agricultural crops. This study aimed to determine phenotypic variability, establish the self-compatibility and intercompatibility index, and calculate the reproductive efficiency index in promising cocoa genotypes, emphasizing the importance of characterization in tree selection. Thirty trees from 7 families of intraspecific hybrids were evaluated. Phenotypic characterization utilized Engels' descriptors. Reproductive systems were assessed through controlled pollinations, and reproductive efficiency was determined by examining fruit formation after natural and controlled pollination. Cocoa trees exhibited variability in qualitative leaf characteristics at the base, apex, and color, as well as leaf size, with a length/width ratio ranging from 2.4 to 3.6. Flowers displayed color variability related to anthocyanin presence, except for the staminode, which was red in all individuals. Fruit variability was noted in shape, apex, basal construction, and surface roughness. Size-related characteristics such as fruit weight (260 to 727 g), shell weight (209 to 568 g), and seed number (29 to 46) also varied. Maturity after manual pollination ranged from 10% to 80%, and natural pollination resulted in fruit formation between 3% and 38%. The reproductive efficiency index for evaluated genotypes ranged from 0.02 to 1.9. In conclusion, significant genetic variability exists in leaf, flower, and fruit characteristics among the evaluated cocoa trees. These genotypes are both self-compatible and inter-compatible, demonstrating diverse reproductive efficiency indices.
  • Item
    Caracterización fisiológica y productiva de 10 accesiones de maní (Arachis hypogaea L.) bajo condiciones de capacidad de campo
    (Ingenieria Agronomica, 2024) Giler Durán, Galo Enrique ; Holguin Salazar, Xavier Eduardo ; " " ; " "
    Peanut (Arachis hypogaea L.) is an important crop for Ecuador's economy, particularly in the Manabí region. However, information on its cultivation is limited and production has declined in recent years. This highlights the need to explore new varieties, diversify cultivation practices, and gather information to enhance production. The objective of this research was to carry out a physiological and productive characterization of 10 peanut accessions in the field. This study was conducted at the Faculty of Agronomic Engineering of the Technical University of Manabí, Lodana parish Km 13.5, Portoviejo-Santa Ana road, Manabí, Ecuador. Seeds from 10 peanut accessions were obtained from the National Germplasm Bank INIAP. A completely randomized block design (CRBD) was used, with 10 treatments and four replications. The physiological and productive performance of the crop was evaluated: leaf area (LA), number of stomata, chlorophyll index (CI), maximum quantum efficiency of photosystem II (Fv/Fm), number of gynophores, number of pods, weight of 100 seeds (g), and yield (Kg ha-1). The results indicate that the accessions are physiologically active. Among the accessions with the highest physiological responses are ECU-11491 with 302.25 cm² of LA, ECU-11465 with 0.831 Fv/Fm at 13:00, and ECU-16477 with 25.75 stomata per mm2 on the adaxial side and ECU-11433 with 22.5 stomata per mm2 on the abaxial side. The CI for all accessions at 08:00 and 13:00 ranges between 34.25 and 41.35 SPAD Units. Accessions with high productive potential were identified, such as ECU-11465 and ECU-11832 with 76 gynophores and 43.75 pods per plant and a yield of 4075.75 Kg ha-1, alongside ECU-11832 with 64.75 gynophores and 40.25 pods per plant, and a yield of 4018 Kg ha-1. ECU-11491 with 66.5 g and ECU-11872 with 62 g are characterized by their high weight of 100 seeds.
  • Item
    Caracterización morfo-cultural y sensibilidad in vitro de aislamientos de Bipolaris sp. obtenidos de arroz (Oryza sativa L.) y pitahaya (Hylocereus undatus Haw.) Britton y Rose a diferentes fungicidas
    (Ingenieria Agronomica, 2024) Briones Bravo, María Cristina ; Lucas Briones, Juleissy Roxanna ; " " ; " "
    The presence of pathogens such as Bipolaris spp. among economically important crops such as dragon fruit and rice, describes the symptoms they cause in these crops. The main objective of the following work was to evaluate the morpho-cultural characteristics and in vitro sensitivity of Bipolaris sp isolates. obtained from rice (Oryza sativa L.) and dragon fruit (Hylocereus undatus Haw.) Britton and Rose to different fungicides. Morphological characterization revealed significant differences between the isolates: those from pitahaya showed circular or irregular colonies, light to dark brown mycelium, and conidia with 2-4 septa (24.15 x 7.31 µm on average). Rice isolates presented greater variability, with similar colonies, light brown to whitish mycelium, and conidia with 2-9 septa (62.08 x 12.46 µm on average). In vitro sensitivity tests showed that penconazole and pyraclostrobin + metiram were the most effective, achieving 100% inhibition of mycelial growth at 0.25 g/L. Other fungicides such as chlorothalonil, metalaxyl + chlorothalonil, cupric compounds and methyl thiophanate caused moderate inhibitions (40-60%). It is concluded that penconazole has great potential to control Bipolaris, although more studies are required given the variability between isolates. The morphological characterization of Bipolaris sp. showed significant taxonomic differences between rice and pitahaya isolates. This research provides a fundamental basis for the accurate identification and development of crop-specific phytosanitary management strategies.
  • Item
    Caracterización morfoagronómica de poblaciones de maíz criollo (Zea mays L.) provincia de Manabí, Ecuador
    (Ingenieria Agronomica, 2024) Murillo Arteaga, Wilson Rafael ; " " ; " "
    Ecuador is a country with a wide genetic diversity of corn and there are populations of native corn conserved by farmers that have not yet been characterized. These genetic resources could be conserved and used in plant breeding programs. The objective of this research was to characterize morphoagronomically 38 populations of native maize from the Province of Manabí, Ecuador. Plots of 8 m2 were established for each population, with a distance of 0.3 m between plants and 0.8 m between furrows and each furrow was 5 m long; at the Portoviejo Experimental Station of the National Institute of Agricultural Research (INIAP) during the dry season of 2022 (July - December); and 19 quantitative and 11 qualitative morphoagronomic descriptors were used. Cluster analysis showed the formation of four groups, where the populations of hard kernels with large cobs and soft kernels with short cobs were separated into different groups. The quantitative variables ear height, panicle length, percent lodging, number of kernels per row and ear weight recorded "D" indices of 0.75, showing themselves as discriminant variables in the formation of the groups, while the most discriminating qualitative variables were grain type (χ2 = 49.09***, P= 0.742, V= 0.64), grain color (χ2= 51.955***, P= 0.75, V=0.64), row arrangement (χ2= 18.11*, P=0.56, V=0.39), and grain surface shape (χ2 = 20.52*, P=0.58, V=0.41). Native maize races identified were Candela, Cubano, Tuxpeño, Tusilla and Uchima, observing significant genetic diversity in the populations studied. It was concluded that the characterized native corn populations were a valuable genetic resource for the conservation and use of the cereal.
  • Item
    CERCOSPORA LEAF SPOT MANAGEMENT WITH NITROGENOUS FERTILIZERS IN COTTON IS DEPENDENT ON THE DISEASE AMOUNT IN THE PLANT CANOPIES
    (Ingenieria Agronomica, 2024) Parrales Rodríguez, Victor Fernando ; " " ; " "
    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), the Exponential, Gompertz, and Logistic models were employed based on temporal data. The study was designed as a randomized complete block with a 4x4 factorial arrangement (fertilizer type x dose), and mean comparisons were made using Tukey's test (P ≤ 0.05). It was found that disease intensity within each canopy level varied in response to the type of nitrogen source and the applied dose, with the severity of the disease (including the area under the disease progress curve) being particularly influenced. A significant interaction between the type of fertilizer and the dose regarding the intensity of Cercospora leaf spot was observed. The Exponential model most accurately depicted the disease's temporal progression. Notably, poultry manure and urea were the fertilizers that most adversely influenced the intensity and initial inoculum (Y0) of Cercospora leaf spot across the various canopies of the cotton plants. The findings suggest that the use of organic fertilizers in cotton cultivation could represent a viable sustainable management strategy.
  • Item
    Comparación de tecnologías de riego en cultivo de maní (Arachis hypogaea) con diferentes alternativas de nutrición
    (Ingenieria Agronomica, 2024) Murillo Vernaza, Tito David ; " " ; " "
    Agriculture represents the activity with the greatest water demand worldwide, playing a transcendental role in food production. Therefore, the use of this resource in an annual crop such as peanuts is of primary importance, especially if the production areas and climatic conditions are considered, which do not usually satisfy the water requirements of the crop. The objective of the research was to evaluate the morpho-physiological and productive response of the peanut crop with different irrigation techniques and nutrition alternatives. A Bifactorial design was developed with a 2x5 arrangement for a total of 10 treatments with 3 repetitions. The experiment was executed in a completely randomized block in subdivided plots. Significant effects were found for both the irrigation technologies and the nutrition alternatives used in the morphophysiological variables, relative chlorophyll content, stomatal conductance, in the productive ones there were no significant effects in the evaluated variables. Drip irrigation and compost fertilization resulted in the highest values of stomatal conductance with 401 and 432 mmol/m2s, similar behavior occurred with the relative chlorophyll content with values of 51.60 and 53.42 Spad units respectively. The results obtained showed a positive effect of drip irrigation and the application of compost as a nutrition alternative in peanut cultivation, achieving a positive effect on water use by reducing the use of chemical fertilizers in peanut production.
  • Item
    Comparison of Capsicum genotypes under in vitro saline stress induced by different concentrations of NaCl and CaCl2.
    (Ingenieria Agronomica, 2025) Leones Anchundia, Katherine Daniela ; Zambrano Coveña, Danny Josué ; " " ; " "
    Five cultivated species of Capsicum are reported as moderately sensitive to salinity and their germination can be affected by high levels of salts in the soil. The objective of this study was to evaluate the in vitro response of different Capsicum spp. genotypes to salinity and to identify those with greater tolerance to salt stress. For this, eight Capsicum accessions were used, which were subjected to different levels (0.1, 0.3, 0.5, 0.7 and 0.9 g L-1) of sodium chloride (NaCl) and calcium chloride (CaCl2) application under in vitro conditions. The results show that the seeds of the different accessions respond in a varied way to saline treatments. Accessions ECU-2254b of C. annuum and ECU-9123 of C. chinense showed more tolerance to different levels of salinity, while accessions ECU-2237 and ECU-12970b of C. frutescens were the most susceptible. These results provide valuable information for genetic breeding programs seeking to develop Capsicum cultivars with greater tolerance to abiotic factors such as salinity, which is crucial to improve productivity in these areas.
  • Item
    Comportamiento agronómico de dos variedades de lechuga (Lactuca sativa L.) con diferentes dosis de solución nutritiva, bajo hidroponía
    (Ingenieria Agronomica, 2023) Bazurto Moreira, Adonis Geovany ; Pin Suárez, Kevin Leonardo ; " " ; " "
    Hydroponics is a technique that allows to produce plants without the use of soil, and is considered an alternative method in horticultural production since it has proven to be a feasible option to avoid the inconvenience with soil erosion caused by inadequate agriculture and the use of chemicals. The research aimed to evaluate the agronomic behavior of two varieties of lettuce (Lactuca sativa L.) var. Crespa and var. Capitata with different doses of nutrient solution, under a hydroponic nutrient film system (NFT). A completely random design with bifactorial arrangement (2X4) was used, studying two varieties of lettuce (Crespa and Capitata) for four doses of nutritional solution (DS 1: 1.0 ml/L, DS 2: 1.5 ml/L, DS 3: 2.0 ml/L, DS 4: 2.5 ml/L), totaling 8 treatments.
  • Item
    Comportamiento de dos genotipos de algodón (Gossypium hirsutum L.) ante el déficit hídrico durante la fase de floración
    (Ingenieria Agronomica, 2023) Salavarria Bravo, Lady Jamileth ; " " ; " "
    Cotton (Gossypium hirsutum L.) is the most important non-food agricultural crop in the world, being the main natural fiber planted. However, both the development and the productivity of this crop are severely affected by the restriction in the water supply. The objective of this study was to evaluate the behavior of two cotton genotypes (Cocker 310 and DP Alcala 90) in the face of water deficit during the flowering phase. This research was carried out in a shade house, where the two genotypes grew with an irrigation sheet of 16 L/m2 per day, until 30 days after sowing; from that moment part of the plants of each genotype were subjected to water deficit by suspending irrigation during the entire flowering phase, leaving in parallel a control treatment that continued to be irrigated with the already indicated sheet. Thirty days after the start of the water deficit period, the following variables were determined: stem diameter, plant height, number of leaves, number of flower buds, number of flowers, root depth, root volume, dry weight of root, stem, leaves and flowers, root/shoot ratio, leaf area, chlorophyll index and relative water content. The results obtained showed that all the variables determined were reduced under the condition of water deficit, in relation to the control treatment, this behavior being more accentuated in the Cocker 310 variety, except for the root depth, the root/shoot ratio and the relative content of chlorophyll in the leaf, since the value of these three variables increased with water stress in both genotypes. The results obtained suggest that the flowering phase is quite sensitive to water deficit, with the DP Alcala 90 variety being the one that was less affected by the water deficit condition.
  • Item
    Comportamiento de nuevos híbridos de maíz (Zea mays L.) en sistemas de producción de alta densidad con fertilización de liberación controlada, en la parroquia Lodana
    (Ingenieria Agronomica, 2025) De La Vera Vinces, Milena Meluvi ; Vargas Loayza, Ángeles Belén ; " " ; " "
    Corn (Zea mays L.) is essential for both human and animal consumption and in the food industry. In Ecuador, especially in the Coastal region, large areas of corn are cultivated, but the yield per hectare remains low, which requires optimizing agricultural practices such as planting density and fertilization. This study evaluated the behavior of two new corn hybrids under high-density planting systems and controlled fertilization in the Lodana parish, Manabí; through the use of a completely randomized block design with 27 experimental treatments, combining planting densities, hybrids and fertilizers, where growth and performance variables were evaluated. The results obtained indicate that high densities in combination with controlled release fertilization did not show significant effects on vegetative growth, but the hybrids and fertilization did influence the insertion height of the cob, highlighting the ADV-9139 hybrid. In terms of yield, high densities and hybrids had significant effects on variables such as the number of grains per row and yield per hectare, with ADV-9139 and N-25 being the most productive. Combined fertilization (conventional and controlled release) turned out to be an economically viable strategy, reducing costs and increasing profits. Therefore, the use of hybrids such as ADV-9139 and N-25, high population densities and combined fertilization is recommended to optimize the productivity and profitability of corn cultivation.
  • Item
    Comportamiento de plagas y enfermedade en el cultivo de Citrus aurantifolia (Christm.) y Citrus latifolia (Tanaka) en Latinoamérica y Ecuador.
    (Ingenieria Agronomica, 2022) Mero Casanova, Valeria Guadalupe ; Quijije Muñoz, María Angélica ; " " ; " "
    THE MEXICAN LEMON, CITRUS AURANTIIFOLIA, AND THE TAHITI LIME, CITRUS LATIFOLIA ARE IMPORTANT CITRUS FRUITS DUE TO THEIR DEMAND AS FRESH OR PROCESSED PRODUCTS. LATIN AMERICA PRODUCES 35% OF THE LIMES AND LEMONS CONSUMED IN THE WORLD. ITS CULTIVATION COULD BE AFFECTED BY EXOTIC AND NATIVE PHY-TOSANITARY PROBLEMS. THE OBJECTIVE OF THIS RESEARCH WAS TO ANALYZE THE OCCURRENCE AND IMPACT OF DISEASES AND PESTS IN C. AURANTIIFOLIA AND C. LATIFOLIA IN LATIN AMERICA. A REVIEW WAS CARRIED OUT IN DIFFERENT DATABASES, SUCH AS ACADEMIC GOOGLE, FAO AND EPPO. THE MAIN BACTERIAL AND FUNGAL DISEASES REPORTED ARE: CANKER CAUSED BY XANTHOMONAS CITRI SSP. CITRI, AN-THRACNOSE DUE TO COLLETOTRICHUM GLOEOSPORIOIDES AND COLLETOTRICHUM ACUTATUM AND GUMMOSIS ASSOCIATED WITH, PHYTOPHTHORA PARASITICA. AMONG THE VIROSIS, THE LEPROSIS VIRUS AND THE CITRUS TRISTEZA VIRUS, TRANSMITTED BY MITES, BREVIPALPUS SPP. AND TOXOPTERA CITRICIDA, RESPECTIVELY. PHYLLOCNISTIS CITRELLA IS CONSIDERED A PRIMARY PEST THAT BUILDS GALLERIES IN THE LEAVES, DEFORMING THEM AND AFFECTING THEIR DEVELOPMENT. THIRTY ONE TAXA OF COCCOIDEA AND FIVE OF WHITEFLIES (ALEYRODIDAE) WERE REPORTED. HOWEVER, THE MOST RELEVANT PHYTOSANITARY PROBLEM IS HUANGLONGBING (HLB) DE-TECTED IN THE AMERICAS IN BRAZIL IN 2004. IT IS CAUSED BY THE BACTERIA CANDI-DATUS LIBERIBACTER SPP. AND TRANSMITTED BY DIAPHORINA CITRI. THE PRODUCTION OF LIMES AND LEMONS IN LATIN AMERICA HAS FACED CHALLENGES IN DISEASE AND PEST MANAGEMENT. WHILE TECHNOLOGIES ARE GENERATED TO REDUCE THE DAMAGE CAUSED BY HLB AND OTHER PHYTOSANITARY PROBLEMS, CITRUS GROWERS MUST UNDERTAKE STRATEGIES THAT ALLOW THEM TO MANAGE THEM RATIONALLY AND AT THE SAME TIME MAINTAIN PRODUCTION LEVELS.
  • Item
    Crecimiento de dos híbridos de pimiento (Capsicum annuum L.) en condiciones de campo abierto y macro túnel
    (Ingenieria Agronomica, 2023) Torres Ubillús, Samuel Moisés ; " " ; " "
    The present investigative work was carried out on the premises of the Faculty of Agricultural Engineering in Lodana, Santa Ana parish and the objective was to evaluate the growth behavior of two pepper hybrids (Capsicum annuum L.) under macro tunnel conditions and in the field. open, evaluating morphological parameters and chlorophyll content. The methodology used is the completely randomized experimental design (DCA), as a process four treatments and four repetitions were used with the two hybrids of pepper, where growth under macro tunnel conditions and in the open field. The variables stem height and diameter, number, length and width of leaves and the chlorophyll index were evaluated. The results obtained in morphological parameters (plant height, active leaves, stem diameter and chlorophyll content) show that the Quetzal cultivar showed the highest values in the three evaluation moments under macro tunnel conditions.