Scientia Agropecuaria

Estimation of evapotranspiration from UAV high-resolution images for irrigation systems in rice fields on the northern coast of Peru

Resumen Ante la creciente escasez del agua para la agricultura, el incremento de la demanda de alimentos y los futuros escenarios de sequía que nos plantea el cambio climático es indispensable diseñar nuevas tecnologías que contribuyan a un menor consumo de agua. En esta investigación se han empleado imágenes de alta resolución para estimar la evapotranspiración en arrozales aplicando el modelo de balance de energía METRICTM (Mapping Evapotranspiration at High Resolution using Internalized Calibration). Para ello, se monitorizaron 5900 m2 de cultivo bajo riego por inundación continua (IC) y 2600 m2 bajo la técnica de riego de alternancia humedecimiento y secado (AWD, por sus siglas en inglés), además de algunas parcelas con filtración lateral. Se realizaron 10 vuelos entre las etapas de macollamiento y floración, cinco vuelos con un VANT Matrice 210 con una cámara multiespectral Parrot Sequoia, y cinco vuelos con un Matrice 300 RTK equipado con una cámara térmica H20T. Se colectó información de campo de los índices de vegetación (NDVI e IAF), y lecturas de un radiómetro, para ajustar información de las imágenes multiespectrales y térmicas, respectivamente; y obtener los componentes del balance de energía en superficie. Se obtuvo valores medios para evapotranspiración del cultivo (ETc) de 6,34 ±1,49 y 5,84 ± 0,41 mm d-1 para riego IC y riego AWD, respectivamente, obteniéndose un ahorro de agua del 42% con una reducción del rendimiento en 14%, proporcionando una guía para la gestión adecuada del riego, sin embargo, se sugiere utilizar el modelo para optimizar el rendimiento obteniendo umbrales críticos para la aplicación óptima de AWD frente a la escasez del recurso hídrico.

Abstract In view of the growing scarcity of water for agriculture, the increase in food demand and future drought scenarios posed by climate change, it is essential to design new technologies that contribute to lower water consumption. In this research, high-resolution images have been used to estimate evapotranspiration in rice fields by applying the METRICTM (Mapping Evapotranspiration at High Resolution using Internalized Calibration) energy balance model. For this purpose, 5900 m2 of crop were monitored under continuous flood irrigation (CF) and 2600 m2 under alternate wetting and drying irrigation (AWD), in addition to some plots with lateral filtration. Ten flights were conducted between tillering and flowering phases, five flights with a Matrice 210 UAV equipped with a Parrot Sequoia multispectral camera, and five flights with a Matrice 300 RTK equipped with a H20T thermal camera. Field data were collected from vegetation indices (NDVI and LAI), and readings from a radiometer, to adjust information from multispectral and thermal images, respectively, and to obtain the components of the surface energy balance. Mean values for crop evapotranspiration (ETc) of 6.34 ± 1.49 and 5.84 ± 0.41 mm d-1 were obtained for IC irrigation and AWD irrigation, respectively, obtaining a water saving of 42% with a yield reduction of 14%, providing a guide for proper irrigation management, however, it is suggested to use the model to optimize yield by obtaining critical thresholds for optimal application of AWD in the face of water resource scarcity.

New educational approach for the sustainability of natural forest capital: review, analysis and conceptual contributions on the natural capital of the Romerillo forest

Abstract The concept of Natural Capital of the Romerillo forests (NCR) has been little studied in relation to the Education of this important type of natural capital. However, currently, many researchers have argued that Education can contribute significantly to the teaching and learning of this natural capital. By investigating how the concept has been studied, this article has attempted to establish the direction, understanding and use of Education that the NCR may take in the future, within the context of research into an Intangible Creative Ecological Economy (ICEE). This study used an exploratory research methodology with secondary information, in combination with chronological, conceptual and thematic literature review techniques. The literature review indicates that Education on NCR has been used in three areas of research to explain or address a particular construct: (1) promotion of formal and informal programs for use of the intangible environmental services, (2) development of an ICEE that promotes biotrade of intangible services from the Romerillos forests, and (3) short- and long-term conservation of the Romerillos forests. For future studies, it is recommended to address the concept of Education in “Intangible Forest Natural Capital” as a strategy for the sustainable use of the intangible environmental services of the NCR, aiming to mitigate deforestation and preserve the forests of the Romerillos Andean.

Molecular inclusion encapsulation of orange essential oil: Effect of the drying method on physical, chemical, structural characteristics and stability

Resumen Previas investigaciones sugieren al aceite esencial de naranja como un antimicrobiano y antioxidante natural; sin embargo, la alta volatilidad y sensibilidad a factores externos limita sus aplicaciones. En ese sentido, la encapsulación resulta en una alternativa de protección ideal para los aceites esenciales, y la inclusión molecular tiene ventajas frente a otros métodos de encapsulación, pero el método y temperatura de secado puede influenciar en sus características y estabilidad. Por esta razón, se microencapsuló al aceite esencial de naranja en beta-ciclodextrina (β-CD); y se evaluó el efecto del secado por estufa, liofilización y atomización (160, 180 y 200 °C) sobre la humedad, actividad de agua, eficiencia de encapsulación, rendimiento y estabilidad (82% de humedad relativa por 36 días). Las micropartículas fueron analizadas mediante microscopía electrónica de barrido (MEB), y espectroscopia infrarroja por transformada de Fourier (FTIR). El mejor método de secado fue la liofilización alcanzando una eficiencia de encapsulación de 97,35%, humedad 1,76%, actividad de agua 0,54, y una baja higroscopicidad de 0,20%. Los resultados por FTIR encontraron la formación y pérdida de algunos enlaces en el aceite esencial de naranja y la beta-ciclodextrina, posiblemente por efecto de la temperatura. Las micropartículas liofilizadas presentaron una mejor estabilidad en el almacenamiento logrando una eficiencia final de 52,53% con baja humedad y actividad de agua. Este estudio permite establecer el mejor método de secado en casos de una inclusión molecular; lo cual puede ser útil en aplicaciones futuras al desarrollar productos.

Abstract Previous investigations suggested the orange essential oil as antimicrobial and natural antioxidant; however, the high volatility and sensibility due to extern factors are imitating its applications. Thus, the encapsulation is an ideal alternative of protection for essentials oils and the molecular inclusion has greater advantages compared to others, but the drying method and temperature can influence its characteristics and stability. Therefore, the orange essential oil was microencapsulated into beta-cyclodextrin (β-CD), and was evaluated the effect of drying by stove, lyophilization and atomization (160, 180 and 200 °C) on humidity, water activity, encapsulation efficiency, yield, and stability (82% relative humidity for 36 days). The microparticles were analyzed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). The best drying method was lyophilization achieved an encapsulation efficiency of 97,35%, humidity 1,76%, water activity 0,54, and low hygroscopicity 0,20%. The results by FTIR found the formation and loss of some bonds between orange essential oil and beta-cyclodextrin, probably by effect of temperature. The lyophilized microparticles presented best stability with final efficiency of 52,53% with low humidity and water activity. This study makes it possible to establish the best drying method in cases of molecular inclusion, which may be useful in future applications when developing products.

Identification of Aspergillus westerdijkiae and its potential risk of Ochratoxin A synthesis in Cannabis inflorescences

Abstract Nowadays, fungal contamination of medical Cannabis inflorescences during postharvest has become an increasingly frequent and worrisome problem for consumers and the industry in general. This is because some of these microorganisms can produce secondary metabolites, such as mycotoxins, which can be toxic to humans. To assess the risk posed by fungal contamination and evaluate the potential for fungal isolates to produce mycotoxins, samples of medicinal Cannabis were tested for the presence of mycotoxin-forming fungi. Inflorescences were isolated on PDA agar at 23 ± 2 °C for ten days, and the microorganisms were identified. The strain with morphological characteristics compatible with the genus Aspergillus spp. was selected as the fungus with the highest risk of forming hazardous mycotoxins. This isolate was characterized conventionally and by molecular identification using primers for the internal transcribed spacer region (ITS) of ribosomal DNA and different coding genes and was identified as Aspergillus westerdijkiae. To determine mycotoxin formation, the genome of A. westerdijkiae was sequenced using the Illumina Novaseq platform in South Korea. The antiSMASH tool was used to search for gene clusters associated with producing secondary metabolites, and genes related to toxins were manually curated. Regions where the cluster of genes directly involved in OTA biosynthesis (otaA, otaB, otaC, otaR and otaD) were found, suggesting a potential risk of synthesis of this toxin.

Bee pollen as a functional ingredient in bread: an exploratory study based on attitudes and expectations of Brazilian consumers

Abstract This study investigated consumers' perceptions of adding bee pollen to bread. An attitude questionnaire composed of 48 statements related to "general health," "light products," "natural products," "salty products," "food as a reward," "pleasure," and "food neophobia" was answered by the participants, who indicated their level of agreement with each statement according to a 5-point Likert scale, ranging from (1) "totally disagree" to (5) "totally agree." A check-all-that-apply (CATA) questionnaire was also employed to characterize 12 visual stimuli. The creation of stimuli was carried out using a factorial design, resulting in 12 images of bread. Three clusters of consumers were identified, each associating positive attributes with stimuli containing bee pollen, regardless of the health claim, while negative attributes were associated with stimuli without added pollen. The main positive drivers of liking were "I would buy," "attractive," "pleasant color," "healthy," "light," and "natural." On the other hand, the negative drivers of liking were "unattractive," "I don't like it," "I wouldn't buy," "hard," and "unpleasant color." This study provides valuable information for developing healthier bread using natural ingredients with bioactive compounds, such as bee pollen.

Watershed scale soil moisture estimation model using machine learning and remote sensing in a data-scarce context

Abstract Soil moisture content can be used to predict drought impact on agricultural yield better than precipitation. Remote sensing is viable source of soil moisture data in instrument-scarce areas. However, space-based soil moisture estimates lack suitability for daily and high-resolution agricultural, hydrological, and environmental applications. This study aimed to assess the potential of the random forest machine learning technique to enhance the spatial resolution of remote soil moisture products from the SMAP satellite. Models were built using random forest for spatial downscaling of SMAP-L3-E, then visually and statistically evaluated for disaggregation quality. The impact of topography, soil properties, and precipitation on the downscaled soil moisture was examined. The relationship between downscaled soil moisture and in-situ soil moisture was analyzed. The results indicate that the proposed method demonstrated spatial and hydrological coherence, along with a satisfactory downscaling quality. Statistical validation indicated suitable generalization error for scientific and practical use (RMSE < 0.05 cm3 cm-3). Random forest effectively achieved spatial downscaling of SMAP-L3-E in the study area. Principal component and spatial analysis revealed dependence of downscaled soil moisture on elevation, soil organic carbon content, clay content, and saturated hydraulic conductivity, mainly under near-saturation conditions. Regarding validation against in-situ data, downscaled soil moisture explained in-situ soil moisture well under low soil water content (ρ = 0.624). Downscaling performance deteriorates for water contents between 0.40 to 0.50 cm3 cm-3, suggesting inadequacy under near saturation conditions at a daily temporal frequency. However, coarser temporal aggregations (7 to 10 days) yielded an average 0.98 correlation coefficient, regardless of saturation conditions. These results could potentially be applied in irrigation planning, soil physics studies and hydrology monitoring, to forecasting the occurrence of droughts, leaching of contaminants, surface runoff modeling, carbon cycle studies, soil's capacity to store and provide nutrients. Our results could mainly be applied to understanding the impact of droughts on crop yield.

Dynamics of growth, sporulation and capture of asexual fungi on Meloidogyne sp., in vitro

Resumen Los nematodos formadores de agallas son perjudiciales para los cultivos agrícolas. El objetivo de esta investigación fue evaluar el crecimiento, esporulación y captura de hongos asexuales contra Meloidogyne sp. en condiciones in vitro. La identificación molecular de los hongos asexuales se realizó con PCR utilizando secuencias de la región ITS del ADNr. Se evaluó el crecimiento y esporulación de Arthrobotrys, Dactylellina y Dactylaria en cinco medios de cultivos y dos tipos de substratos (cascarilla de arroz y maíz molido). Para la evaluación de atracción y captura de los nematodos se emplearon juveniles de segunda etapa de Meloidogyne sp. Todos los aislamientos fúngicos evaluados crecieron y esporularon en los medios de cultivos y substratos. Los hongos Arthrobotrys sp. (C19-1-1) y Dactylellina sp. (C19-48) mostraron mayor efectividad en la atracción y captura de Meloidogyne sp. Los aislamientos fúngicos evaluados tienen el potencial de colonizar diferentes medios de cultivos y substratos. Además, pueden formar hifas modificadas y especializadas que controlan nematodos juveniles de Meloidogyne sp. Por lo tanto, los futuros estudios se deberían centrar en evaluar los aislados fúngicos contra los nematodos formadores de agallas en condiciones de campo.

Abstract Root-knot nematodes are detrimental to agricultural crops and hard to control once established in the field. The objective of this research was to evaluate the growth, sporulation, and capture in vitro of asexual fungi against Meloidogyne sp. Molecular identification of the asexual fungi included in the study was performed by sequencing the ITS1 region of rDNA. The growth and sporulation of Arthrobotrys sp., Dactylellina sp. and Dactylaria sp. was evaluated in five culture media and two types of substrates (rice husks and ground corn). For the evaluation of attraction and capture of the nematodes, second stage juveniles of Meloidogyne sp. All the evaluated fungal isolates grew and sporulated in the culture media and substrates. The fungi Arthrobotrys sp. (C19-1-1) and Dactylellina sp. (C19-48) showed greater effectiveness in attracting and capturing Meloidogyne sp. The evaluated fungal isolates have the potential to colonize different culture media and substrates. In addition, they can form modified and specialized hyphae that control juvenile Meloidogyne sp. nematodes. Therefore, future studies should focus on evaluating fungal isolates against root-knot nematodes under field conditions.

Effect of moderate heat stress on tuberization of potato genotypes: Morphological and physiological changes using in vitro and ex vitro propagation

Abstract Potato plants are often subjected to heat stress during growth and development, resulting in loss of yield and quality. However, the possibility exists that commercially important genotypes show tolerance to heat stress. In this study, we aim to investigate the morphological and physiological effects of moderate conditions of heat stress on tuberization in nine potato genotypes, and how it affects propagation using an ex vitro and in vitro system. The plant material came from the In Vitro Germplasm Bank of the International Potato Center (CIP). The incubation temperatures of the cultures in in vitro and ex vitro conditions were the ambient in the laboratory and greenhouse, respectively. In in vitro system a randomized complete block design was employed in nine genotypes, two treatments: multiplication culture medium and the same culture medium supplemented with 8.0% sucrose and 500 mg/L-1 CCC, six flasks and five explants per experimental unit. Among all genotypes evaluated, Leona and Liberteña did not form tubers under ex vitro treatment conditions. Under in vitro conditions, Amarilis, Capiro, Perricholi and Tacna showed no evidence of tuberization, and Canchán was the only genotype where 100% formation of tuberous structures were produced in all evaluations. The findings concluded in this study showed that of all the potatoes evaluated, Canchán best responded to the evaluations under both in ex vitro and in vitro conditions, at maximum temperatures between 22.4 to 26.9 and 27.0 to 28.2 oC, respectively. Therefore, it is vitally important to consider its development potential in different producing locations around the world, which are directly and indirectly affected by climate change.

Emerging non-thermal technologies in the food industry: Advances and potential applications in food processing

Resumen En la actualidad, la industria alimentaria da prioridad a la seguridad y calidad de los productos, enfrentándose al desafío de mantener la integridad sensorial y nutricional. Para abordar este desafío, se vienen explorando tecnologías no térmicas emergentes que ofrecen ventajas significativas en la mejora de la calidad de los alimentos frente a las tecnologías convencionales. Esta revisión tiene como objetivo proporcionar una comprensión integral de cómo estas tecnologías innovadoras pueden transformar el panorama tradicional del procesamiento de alimentos tal como lo conocemos. Las tecnologías no térmicas tienen el potencial de reducir el consumo de energía destinado a la producción, procesamiento y envasado de alimentos, en comparación con los tratamientos térmicos convencionales. Además, estas tecnologías son particularmente adecuadas para preservar eficientemente los compuestos bioactivos presentes en los alimentos. En esta revisión se describen los principios fundamentales, aplicaciones, ventajas y limitaciones de las tecnologías emergentes en el procesamiento de alimentos. En estas tecnologías se incluyen, campo eléctrico pulsado, ultrasonido, plasma frío, alta presión, irradiación, diodos emisores de luz, luz pulsada y campos magnéticos oscilantes. A pesar de la gran cantidad de estudios respecto al tema, se requiere mayor investigación para optimizar y mejorar la eficiencia de la aplicación de estas tecnologías, solas o en combinación, en el procesamiento de alimentos. La bioaccesibilidad y bioactividad de los compuestos, el valor nutricional, la vida útil y los aspectos sensoriales pueden ser variables de interés.

Abstract Currently, the food industry prioritizes the safety and quality of products, facing the challenge of maintaining sensory and nutritional integrity. To address this challenge, emerging non-thermal technologies are being explored that offer significant advantages in improving food quality over conventional technologies. This review aims to provide a comprehensive understanding of how these innovative technologies can transform the traditional food processing landscape as we know it. Non-thermal technologies have the potential to reduce energy consumption for food production, processing and packaging, compared to conventional thermal treatments. Furthermore, these technologies are particularly suitable for efficiently preserving bioactive compounds present in foods. This review describes the fundamental principles, applications, advantages and limitations of emerging technologies in food processing. These technologies include pulsed electric field, ultrasound, cold plasma, high pressure, irradiation, light-emitting diodes, pulsed light and oscillating magnetic fields. Despite the large number of studies on the subject, more research is required to optimize and improve the efficiency of the application of these technologies, alone or in combination, in food processing. The bioaccessibility and bioactivity of the compounds, nutritional value, shelf life and sensory aspects may be variables of interest.

Antimicrobials in global salmon farming: Resistance, effect on human health and the environment, and future perspectives

Resumen La salmonicultura frente a la resistencia de los antimicrobianos y los efectos sobre la salud humana y medio ambiente. Resumen: La presente revisión recopila y analiza estudios de los últimos 5 años sobre uso de antimicrobianos en la industria del salmón, efectos reportados en peces y seres humanos, y los impactos sobre el medio ambiente. Existe una creciente preocupación respecto al manejo actual de los planes terapéuticos veterinarios empleados para el tratamiento y control de infecciones bacterianas. Las principales problemáticas están relacionadas con el aumento en la resistencia hacia antimicrobianos por parte comunidades bacterianas patógenas y no patógenas, la transferencia horizontal de genes de resistencia entre células bacterianas y, un mayor número de casos de tratamientos médicos fallidos en poblaciones humanas y animales. Por lo tanto, los desafíos a futuro serán reducir la dependencia hacia los antimicrobianos en producciones animales mediante la investigación de tecnologías alternativas, la recopilación de información epidemiológica de sectores productivos que permitan realizar monitoreo detallado en las diferentes fases de cultivo, medidas de bioseguridad desde un enfoque de “One Health” y, una supervisión estricta en la formulación de medicamentos por parte de los profesionales en el área animal.

Abstract Salmon farming in the face of antimicrobial resistance and effects on human health and environment. Abstract: The present review compiles and analyzes studies of the last five years on antibiotic use in the salmon industry, reported effects on fish and humans, and impacts on the environment. There is a growing concern regarding the current management of veterinary therapeutic plans used for the treatment and control of bacterial infections. The main problems are related to the increase of resistance to antibiotics by pathogenic and non-pathogenic bacteria communities, horizontal transfer of resistance genes between bacterial cells, and a major number of cases of failed medical treatments in human and animal populations. Therefore, the challenges for the future will be to reduce dependence on antibiotics in animal production through research into alternatives technologies, the collection of epidemiological information from productive sectors that allow detailed monitoring in the different cultivation phases, biosafety measures from an approach of One Health, and strict supervision in the formulation of medicines by professionals in the animal area.

Bioactive compounds from bacterial and fungal agents for the control of phytopathogenic nematodes: mechanisms of action, interactions, and applications

Resumen Los nematodos fitopatógenos son una amenaza para la producción agrícola, causando enfermedades en las plantas y pérdidas económicas en todo el mundo. En la actualidad, la búsqueda de compuestos de origen biológico para estos nematodos, como una alternativa amigable con el ambiente, se ha convertido en prioridad. Los compuestos derivados de microorganismos cuentan con diferentes mecanismos de acción para reducir las poblaciones de juveniles infecciosos de nematodos. A pesar de que la literatura reporta revisiones sobre los microorganismos y sus metabolitos nematicidas, no se destacan las interacciones entre hongos, bacterias y nematodos, así como de los compuestos que se generan en tales interacciones. El objetivo de esta revisión fue discutir los avances recientes sobre compuestos químicos secretados por microorganismos y mecanismos de interacción para el control biológico de nematodos fitopatógenos. Los resultados se organizaron en función de i) mecanismos de acción, ii) proceso de infección, iii) compuestos nematicidas, iv) interacciones y aplicaciones a las soluciones en campo y v) desafíos actuales. El enfoque de esta revisión contribuye a una mejor comprensión de la utilidad de los compuestos producidos por bacterias y hongos que permitan incorporarlos en el desarrollo de planes de manejo para el control de nematodos.

Abstract Phytopathogenic nematodes are a threat for agriculture, they cause plant diseases and economic losses worldwide. Currently, the pursuit of compounds of biological origin for nematode biocontrol has become a priority as an environmentally friendly alternative. Microorganisms-derived compounds have several strategies to reduce the populations of infectious juvenile nematodes. Although microorganisms and their metabolites are the focus of literature reports reviews on nematicidal control, interactions between fungi, bacteria, and nematodes, as well as the compounds that are generated in such interactions, are not highlighted. The aim of this review was to discuss the latest advances on chemical compounds secreted by microorganisms and their interaction mechanisms for biological control of phytopathogenic nematodes. Results were organized based on: i) mode of action, ii) infection process, iii) nematicide compounds, iv) interactions and field applications, and v) current challenges. The scope of this review contributes to a better comprehension of the versatility of bacterial and fungal compounds for their use in the development of management plans for nematode control.