Scientia Agropecuaria

Diversity of arbuscular mycorrhizal fungi and Soil Physicochemical Parameters in Forest Species of the Abras de Mantequilla Wetland, Ecuador

lun, 16 dic 2024 00:00:00 +0000

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 properties. Number of AMF species were found in the four soils in the range of 16 to 39; Number of por Several AMF lowest por the lowest (16) and highest (39) AMF species were found in E. pustulescens and A. guachapele soils, respectively. AMF species ‘Akent’ was the most dominant (abundance #16) AMF species found in the soils of C. peltate. The ranges of Shannon_H and Simpson_1-D values were found to be 1.78-1.9 and 0.79-0.85, respectively. These insights are important to understanding soil-plant-microorganism interactions in promoting sustainable agricultural practices in the Abras de Mantequilla wetland.

Biodegradable trays made from Poraqueiba sericea Tulasne seed starch and Zea mays cob flour

lun, 16 dic 2024 00:00:00 +0000

The environmental impact of polystyrene and other petrochemical packaging has increased interest in researching biodegradable materials as alternatives. The main objective of this research was to develop biodegradable trays from five formulations of Poraqueiba sericea Tulasne (known as umari) seed starch and corncob meal. The trays were produced using the thermoforming process applying temperatures of 135 °C and 145 °C for each side of the tray for a time of 6.5 min. Physical analysis of the trays showed that the increase in the percentage of corn cob flour caused changes in color (L*: 68.69 - 64.94), thickness (2.20 - 3.17 mm), density (0.251 - 0.414 g/cm³), moisture (3.85% - 5.68%), water absorption (21.86% - 39.05%), volatile solids (95.33% - 98.31%). Regarding mechanical properties, it was also evidenced the increase in hardness (67.70 - 90.97 N), fracturability (1.43 and 3.19 mm), tension (2.84 to 3.43 MPa) and elongation (1.54% to 2.04%). The formulation of 87.5% umari seed starch and 12.5% corncob flour presented more favorable physical and mechanical properties. Further analysis of this formulation was performed by Fourier transform infrared spectroscopy (FTIR), which identified bands characteristic of starch (1055 and 1027 cm^-1); X-ray diffraction (XRD), which revealed characteristic peaks (2θ = 16.83° and 2θ = 22.69°) associated with cellulose crystallinity in the biodegradable tray; and scanning electron microscopy (SEM), which revealed cellulosic voids with irregular distribution due to the addition of fibers. Future research should examine the potential applications of these biodegradable trays for the packaging of raw materials in the food industry.

La floricultura como cultivo alternativo: Análisis descriptivo, modelación con inteligencia artificial, análisis de escenarios y análisis económico

Peter Coaguila-Rodriguez, Vicente Serapio Pocomucha-Poma, Franco Cerna-Cueva — mar, 14 ene 2025 00:00:00 +0000

La floricultura es un sector de creciente importancia a nivel mundial, contribuyendo a la generación de empleo, ingresos y a la promoción de la biodiversidad y la sostenibilidad. Este estudio tuvo como objetivo identificar los factores que influyen en la adopción de la floricultura como cultivo alternativo en la provincia de Leoncio Prado, Perú, y evaluar su viabilidad económica. Para ello, se encuestó a 269 agricultores, analizando actitudes, aptitud de la tierra, factores socioeconómicos y ambientales. Mediante análisis descriptivo, pruebas de chi-cuadrado y regresión logística (p < 0,1) se seleccionaron los factores influyentes. Además, se emplearon múltiples algoritmos de aprendizaje automático (Árboles de Decisión, Regresión Logística, KNN, SVM, Ensemble, Redes Neuronales, Naive Bayes) con validación cruzada (k = 5) y métricas AUC para modelar la intención de adopción. Se desarrollaron escenarios incrementando la predisposición a adoptar la floricultura, y se realizó un análisis económico de ocho especies tropicales (Ginger Rojo, Anturio, Bastón del Emperador, Heliconia, Gardenia, Pico de Loro, Heliconias Golden, Maracas). Los resultados revelan que la disposición a cambiar de cultivo, la participación en campañas de sensibilización, la destinación de áreas a la conservación y el control de costos son factores clave. El modelo de redes neuronales alcanzó un AUC de 83,3% y escenarios mejorados indican que la adopción podría incrementar hasta en 11,32%. El Ginger Rojo demostró alta rentabilidad (VAN S/10428; TIR 51%; PRI 0,7 años). En conclusión, la floricultura representa una alternativa económica y ambientalmente viable que contribuye a la diversificación agrícola y a la sostenibilidad.

Biochemical and enzymatic alterations of watermelon associated with irrigation management and inoculation with Rhizobacteria

mar, 14 ene 2025 00:00:00 +0000

Water stress has caused major losses in the agricultural productivity of crops, inducing the search for alternatives for sustainable cultivation. In this context, the objective of this study was to evaluate the tolerance of watermelon under water stress, inoculated with bacterial strains of the genus Bacillus spp., regarding the biochemical and enzymatic variables in the flowering stage. A randomized block design was adopted in a split-plot 4x4 factorial scheme, with plots consisting of four levels of soil water availability (40%, 60%, 80% and 100% of field capacity - FC) and subplots consisting of four inoculations (Negative Control (NC); XX6.9 bacteria; P6.2 bacteria; MIX – co-inoculation of XX6.9 and P6.2 bacteria), with five replicates. XX6.9 bacteria and NC were the treatments most affected by severe water stress, since at the soil water availability (SWA) level of 40% FC they showed high contents of the oxidative marker (MDA) and proline. Although the inoculation with XX6.9 bacteria promoted a higher content of osmoregulators such as proteins, total soluble sugars and reducing sugars, it was not enough to attenuate the effects of water deficit. On the other hand, treatments with P6.2 bacteria and MIX of bacteria showed reduced levels of MDA at the SWA level of 40% FC, accompanied by high enzymatic activity of POD and CAT, which may contribute to the tolerance of the watermelon crop to water stress.

Sapote gum as a new biopolymer suitable emulsion stabilizer: Grapeseed oil ultrasonic emulsification

mar, 14 ene 2025 00:00:00 +0000

Sapote gum (SG) is a new biopolymer with promissory functional properties. This study aimed to determine if SG is a suitable emulsifier for obtaining stable grape seed oil (GSO) emulsions. In the first stage, coarse emulsion concentrations of SG and grapeseed oil - GSO were evaluated, applying the Central Composite Rotational Design (0.59% to 3.41% of SG and 12.93% to 27.07% GSO). For the second stage, using a Centered Face Design – CFD, the resulting emulsion was sonicated at 90, 270, and 450 Watts at 5, 10, and 15 min. Finally, a validation was made. Emulsions were evaluated through microstructure, droplet size, kinetic stability, heat stress, and rheology. Micrographs of the first-stage emulsions showed droplets up to 3.8 μm diameter and a creaming index between 0.00% and 28.39% after 24 h. Optimization indicates that the higher the concentration of gum (3.5%) and GSO (25%), the more kinetically stable emulsions are produced. Ultrasonic emulsions showed no significant difference in droplet size and kinetic stability before 14 days of rest. Ultrasonic validation was made at 450 W for 6 min, resulting in emulsions stable for 20 days and with rheological characteristics interesting for food or cosmetic industries.

Estimativa do conteúdo de nitrogênio na cana-de-açúcar baseado em índices de vegetação derivados de dados Sentinel-2

mar, 14 ene 2025 00:00:00 +0000

A cana-de-açúcar ocupa grande escala territorial no mundo e busca constantemente por mecanismos para monitorar os nutrientes no ciclo de produção da cultura, utilizando métodos não destrutivos. O estudo com objetivo estimar o teor de nitrogênio na folha da cana-de-açúcar foi desenvolvido na safra 2021/2022 sobre dois talhões comerciais de sequeiro cultivares (RB867515 = 50,75 ha) e (CVSP7870 = 48,56 ha) na Usina Energética Serranópolis-Goiás, avaliando a eficiência dos índices bioquímicos de vegetação Fraction of Absorbed Photosynthetically Active Radiation (fAPAR) e Canopy Chlorophyll Content (CCC) processados utilizando modelo de transferência de radiação RTM PROSAIL, comparados aos índices Normalized Difference Vegetation Index (NDVI) e Green Normalized Difference Vegetation Index (GNDVI), processados utilizando modelos matemáticos e razão de bandas. Ambos, baseados em série temporal de dados Sentinel-2 como variáveis de entrada. A validação do Agro-Modelo ocorreu através de análise de tecido foliar coletada em sete avaliações intercaladas durante o período de permanência da cultura no campo. Foi evidenciado a funcionalidade dos quatro índices, destacando o índice bioquímico fAPAR sob a ótica da estatística descritiva (R² = 0,970 e RMSE = 0,46) para o cultivar RB867515 e (R² = 0,940 e RMSE = 0,69) para o cultivar CVSP7870.