Scielo RSS <![CDATA[Scientia Agropecuaria]]> vol. 14 num. 3 lang. es <![CDATA[SciELO Logo]]> <![CDATA[Análisis de la cobertura boscosa del Parque Nacional Tingo María (Perú) utilizando el algoritmo random forest]]> Resumen El establecimiento de áreas naturales protegidas es una de las estrategias más efectivas para conservar los bosques y su biodiversidad, sin embargo; el avance descontrolado de la deforestación producto del cambio de uso para ampliar la frontera agrícola se ha convertido en una amenaza para estas áreas intangibles. La investigación tuvo como objetivo analizar la dinámica de la cobertura boscosa del Parque Nacional Tingo María (PNTM) y su zona de amortiguamiento (ZA) ubicados en la selva alta de la región Huánuco - Perú. Para lo cual se utilizó como insumo principal imágenes Sentinel-2 que fueron clasificadas utilizando el algoritmo Random Forest. Como resultado, se obtuvo los mapas de cobertura de la zona de estudio que corresponde a los años 2017, 2019, 2021 y 2023 logrando una exactitud temática considerable. Durante los periodos de evaluación, las tasas de cambio de bosque a no bosque dentro del PNTM presentaron valores bajos -0,26% (2017 - 2019); -1,24% (2019 - 2021) y -0,02% (2021 - 2023). Mientras que los bosques de la ZA han sufrido una transición dinámica, con tasas de cambio de -2,97%; -4,39% y -1,15% derivado del cambio de uso de las tierras. Las métricas del paisaje sugieren que los bosques del PNTM se encuentran moderadamente fragmentados y los bosques de la ZA se encuentran fuertemente fragmentados, por lo que se concluye que el área natural protegida ha cumplido con el objetivo de mantener la cobertura vegetal.<hr/>Abstract The establishment of natural protected areas is one of the most effective strategies to conserve forests and their biodiversity; however, the uncontrolled advance of deforestation resulting from the change of use to expand the agricultural frontier has become a threat to these intangible areas. This research aimed to analyze the dynamics of forest cover in Parque Nacional Tingo María (PNTM) and its buffer zone (ZA) located in the high jungle of the Huánuco region of Peru. The main input was Sentinel-2 images that were classified using the Random Forest algorithm. As a result, coverage maps were obtained for the study area corresponding to the years 2017, 2019, 2021 and 2023, achieving considerable thematic accuracy. During the evaluation periods, the rates of change from forest to non-forest within the PNTM presented low values -0.26% (2017 - 2019); -1.24% (2019 - 2021) and -0.02% (2021 - 2023). While the forests in the ZA have undergone a dynamic transition, with rates of change of -2.97%; -4.39% and -1.15% derived from land use change. The landscape metrics suggest that the forests of the PNTM are moderately fragmented, and the forests of the ZA are strongly fragmented, which leads to the conclusion that the protected natural area has fulfilled its objective of maintaining vegetation cover. <![CDATA[Assessing the risk of <em>Fusarium oxysporum</em> f. sp. <em>cubense</em> Tropical Race 4 outbreaks in Ecuadorian banana crops using spatial climatic data]]> Abstract The Musaceae family is susceptible to Fusarium wilt (Fw), which is considered the most important disease globally, caused by a group of Fusarium species that includes F. oxysporum f. sp. cubense tropical race 4 (FocTR4). Until recently, FocTR4 was not present in Latin America. However, wilting, chlorosis of leaves, and vascular discoloration (typical symptoms of Fw) were observed in at least a hundred Cavendish plants located in Colombia, Peru and Venezuela in 2019, 2021 and 2022, respectively. Normally, the disease is more severe throughout the warmer and rainy months of the year. Since Ecuador is the world's leading exporter of bananas, including plantains, this study aimed to identify agroclimatic favorability zones for FocTR4 potential incidence in the country, testing linear models to evaluate disease occurrence in relation to climatic conditions and map favorability zones. Most of the banana-producing provinces, including Guayas, Los Ríos, El Oro, Manabí, Santa Elena, and Esmeraldas, presented an estimate ranging from medium-low to very high. In Guayas and Los Rios, the agroclimatic favorability zones of the main Ecuadorian producer provinces for a very high-risk account for almost 50%. This information can help make preventive management decisions in zones with a greater risk of spreading FocTR4. <![CDATA[Can fall armyworm damage decrease depending on the season, maize hybrid, and type of pesticides?]]> Abstract Maize is the third most important grass produced in the world after wheat and rice. Among the limitations of its production, fall armyworm, Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is considered the most relevant pest in which corn is the main host plant. During the dry and rainy seasons of 2021-2022, lots of 1200 m2 were planted including three commercial hybrids, ADV-9139, Trueno NB-7443, and INIAP-551 in which the treatments were evaluated: T1: Sequence of insecticides (CLE) based on chlorantraniliprole, lufenuron, and emamectin benzoate. T2: Biological insecticide based on Bacillus thuringiensis (BT). T3: Methomyl-based treatment (MET). T4: Untreated plot (UP). Plant and cob damage, plant height and cob insertion, and grain yield were evaluated, and an economic analysis was performed. The least damage to plants and cobs was detected in the ADV-9139 hybrid. Regarding pesticides, CLE showed the best damage control in plants and the cobs were less damaged when CLE and BT were applied. Plant height and cob insertion height were lower in the ADV-9139 hybrid in which the highest grain yields were estimated. Plots treated with BT showed the highest increase in grain yield. The results show that the management of this voracious insect can be achieved combining the partial resistance of a maize genotype with pesticide applications with the lowest social, economic and ecological costs. <![CDATA[Effect of heat processing on bioactive compounds of dehydrated (lyophilized) purple mashua (<em>Tropaeolum tuberosum</em>)]]> Abstract Mashua (Tropaeolum tuberosum) is an Andean tuber rich in phenolic compounds and glucosinolates, known for its consumption that allows the prevention and/or reduction of getting diseases. The present research evaluated the effect of different types of post-harvest management (sunny, bleached, and freeze-dried) on glucosinolate content and its relationship with myrosinase activity. It is also important to note that when plant cells are damaged and glucosinolates meet the plant's myrosinase, which hydrolyzes them and degrades them to other compounds. In the present research, the types of glucosinolates, the content of glucosinolates and the activity of myrosinase of the purple variety of fresh raw mashua and in mashua treated by several types of processing were evaluated, including the previous treatment (sunny and unscrewed), the boiling treatment and the microwave treatment, with whitening times of 3, 4, 5 and 6 minutes, being the condition of the tuber at the time of bleaching in whole form and by cutting, to then be subsequently subjected to lyophilization treatments. Five glucosinolatos (GSL) were identified: 5-methylsulfinilpentile, 4-hydroxybenzyl, 4-hydroxy-3-indolylmethyl, benzyl and 4-methoxybenzyl, of which 4-methoxybenzyl glucosinolate is the most abundant, symbolizing 98% and 95% of the total GSL in the purple ecotype. According to the total concentration of glucosinolates found in the studied variety (purple), it must be 74.22 and 110.60 micromoles per gram of dry base (μmol/g dry weight), so mashua can be considered, the edible plant with the highest existing GSL content. <![CDATA[Recent highlights on passion fruit waste valorization: A review]]> Abstract In the present review, with the help of the descriptive method, some main highlights regarding the possibilities for the valorization of passion fruit waste are systematically presented. To the best of the author’s knowledge, there is still no published review in the English-language scientific literature that examines opportunities, prospects and challenges for the valorization of passion fruit waste. For the preparation of the current review, scientific publications referenced in some of the most authoritative world-renowned scientific databases were used (Scopus, Web of Science, PubMed, Google Scholar); book chapters were not included. This review does not aim to cover, compile and describe all the scientific production available under the keywords “passion fruit waste”, but aims to highlight only some major research trends regarding the possibilities of valorization of passion fruit waste. Scientific articles that remained for technical or other reasons beyond the scope of the current review paper could be included in a subsequent updated review. <![CDATA[Identificación molecular y prevalencia de contaminantes fúngicos en semillas de cultivos semestrales]]> Resumen La calidad de las semillas se ve afectada por la contaminación por hongos. Estos ocasionan el aborto, pudrición o necrosis de la semilla, así como el daño de las plántulas que resulta en el desarrollo de enfermedades en etapas posteriores del crecimiento. Su identificación y caracterización es esencial para establecer el manejo apropiado. El objetivo de este trabajo fue identificar y determinar la prevalencia de los contaminantes fúngicos presentes en la semilla de trece variedades vegetales de arroz, soya, maíz y sorgo dulce forrajero producidas en el municipio de El Espinal, Tolima, Colombia. Esta investigación se realizó en el Centro de Investigación Tibaitatá de la Corporación colombiana de investigación agropecuaria AGROSAVIA (Cundinamarca, Colombia) durante el segundo semestre del 2021. Por medio de un blotter test se identificaron los contaminantes fúngicos y su prevalencia en semilla germinada y sin germinar. Se obtuvieron en total 65 aislamientos de hongos que fueron agrupados en veintiocho morfotipos identificados molecularmente (soya 44, arroz 5, sorgo 7, maíz 9). Los géneros Diaporthe y Fusarium fueron los de mayor prevalencia total y en semillas sin germinar. Los hongos encontrados incluyen posibles patógenos como Fusarium spp, Curvularia spp y Diaporthe spp. y hongos saprófitos como Penicillium spp y Aspergillus spp. Los aislamientos de Fusarium equiseti y Diaporthe sp. en semilla soya, Curvularia penniseti en semilla de arroz, Diaporthe melonis en semilla de sorgo y Fusarium verticillioides en semilla de maíz pueden ser considerados como potenciales patógenos transmitidos por semilla que ocasionaron un efecto negativo en la capacidad germinativa.<hr/>Abstract Seed quality is affected by fungal contamination. These cause abortion, rot, or necrosis of the seed, as well as seedling damage that results in the development of diseases in later stages of growth. Their identification and characterization are essential to establish appropriate management. The objective of this work was to identify and determine the prevalence of fungal contaminants present in the seed of thirteen plant varieties of rice, soybean, corn, and forage sweet sorghum produced in the municipality of El Espinal, Tolima, Colombia. This research was carried out at the Tibaitatá Research Center of the Colombian Agricultural Research Corporation AGROSAVIA (Cundinamarca, Colombia) during the second semester of 2021. By means of a blotter test, fungal contaminants and their prevalence in germinated and non-germinated seeds were identified. A total of 65 fungal isolates were obtained, which were grouped into twenty-eight molecularly identified morphotypes (44 soybean, 5 rice, 7 sorghum and 9 corn). The genera Diaporthe and Fusarium were the ones with the highest total prevalence and in ungerminated seeds. The fungi found include possible pathogens such as Fusarium spp, Curvularia spp and Diaporthe spp. and saprophytic fungi such as Penicillium spp and Aspergillus spp. The isolates of Fusarium equiseti and Diaporthe sp. in soybean seed, Curvularia penniseti in rice seed, Diaporthe melonis in sorghum seed and Fusarium verticillioides in corn seed can be considered as potential seed-borne pathogens that caused a negative effect on germination capacity. <![CDATA[Response of the transcription factor BABY BOOM of <em>Arabidopsis thaliana</em> L. in the formation of embryogenic calluses of cocoa leaves (<em>Theobroma cacao</em> L.)]]> Abstract Cocoa (Theobroma cacao L.) is one of the most important economic crops worldwide. The propagation of elite varieties of cocoa has been achieved through somatic embryogenesis, but still one of the main limitations is the low rates of embryo formation, which is a genotype-dependent trait. Manipulation of transcription factors (TFs) such as BABY BOOM (BBM) promotes the transition of cocoa somatic cells from the vegetative to the embryonic state. This work validated the use of clonal cocoa leaves cv. IMC-67 to induce somatic embryogenesis, overcoming their recalcitrant limitation with the help of the introduction of TF-BBM from Arabidopsis thaliana (AtBBM). The vectors were constructed by the Gateway system using the donor vector pENTR/D-TOPO and the expression vector pk7WG2. The overexpression vector pk7WG2:AtBBM was obtained, allowing successful transformation into Agrobacterium tumefaciens GV3101. The AtBBM gene was characterized (1755 base pairs), and its expression was observed in the formation of embryogenic calluses in cocoa leaves. Overexpression of AtBBM allowed the obtainment of a 92% response in the formation of embryogenic callus in cocoa leaves with Agrobacterium-mediated vacuum infiltration and overexpression of the pk7WG2:AtBBM vector. This high transformation efficiency reached with the insertion of the overexpression vector provides validation of transient response of the TF AtBBM in the formation of embryogenic calluses in cocoa leaves of the IMC-67 clone. Through this methodology, it is possible to continue with studies of gene overexpression, insertion, silencing, and gene editing in Peruvian cocoa. <![CDATA[Extraction of bioactive compounds from Peruvian purple corn cob (<em>Zea Mays</em> L.) by dynamic high pressure]]> Abstract The objective of this research was to evaluate the effects of dynamic high pressure at different processing temperatures, on the extraction of bioactive compounds from Peruvian purple corn cob. The purple corn cobs were ground and sieved to then be mixed with an acidified 20% ethanol-water solution (pH 2) in a 1:30 (w/v) ratio. The hydroalcoholic extracts were subjected to maceration and high dynamic pressure processes varying temperature (25 °C to 60 °C) and pressure (0.01 MPa - 60 MPa), and the bioactive compounds content and antioxidant activity were evaluated. The results showed that dynamic high pressure at 60 MPa / 45 °C was capable of obtaining extracts with bioactive compound contents and high antioxidant activity corresponding to those obtained using the conventional process of 2.5 hours / 65 °C. Seven different anthocyanins were identified by liquid chromatography in the extracts obtained by the dynamic high pressure, mainly cyanidin-3-glucoside, pelargonidin-3-glucoside and peonidin-3-glucoside, and their respective malonyl derivatives. The dynamic high pressure increased the extraction of anthocyanins by more than 108% and obtained them in one step, thus appearing as a new alternative, eco-friendly method for the extraction of bioactive compounds from plant tissues. <![CDATA[Validation of the incorporation of emotional response in consumer-based sensory development: case study in Peruvian craft beers]]> Abstract It is important to identify the emotional response and sensorial needs of consumers to get commercial success of the alimentary sector in order to improve the consumption experience. Obtaining attractive characteristics through the application of the Kano model allows increase the consumer satisfaction. Furthermore, the Napping ® -Ultra Flash Profile (UFP) methodology makes it possible that producers of craft beers may well reliably characterize their products. Likewise, the use of External Preference Mapping (EPM) allows the identification of those highly accepted products. In this sense, the goal of the present study was to validate, through the application of EPM, that the incorporation of the Kano model in the sensory design increases consumer satisfaction in turn obtaining the sensory profile of Peruvian craft beers. The Kano model permitted to determine the attractive characteristics of representative craft beers of the Lima market: the presence of exotic fruits, fruity smell, presence of Andean cereals and high alcoholic grade, and, based on these characteristics, a prototype of craft beer was developed. By using Napping ® -UFP, consumers positioned and described the six samples of Peruvian craft beers (five commercial brands and the prototype), we found that the prototype developed showed floral smell, herbal odor, fruity smell, light golden color, bubbly, exotic fruits, and high alcoholic grade. The EPM showed that 80% of consumers scored the prototype with a high grade of taste. Finally, putting together these techniques turns out to be useful in obtaining products that are highly accepted by the consumer and this methodology could be applied to other products. <![CDATA[Redes neuronales convolucionales ResNet-50 para la detección de gorgojo en granos de maíz]]> Resumen El artículo explora el uso de redes neuronales convolucionales, específicamente ResNet-50, para detectar gorgojos en granos de maíz. Los gorgojos son una plaga importante en el maíz almacenado y pueden causar pérdidas significativas en rendimiento y calidad. El estudio encontró que el modelo ResNet-50 fue capaz de distinguir con alta precisión entre granos de maíz infestados por gorgojos y granos sanos, logrando valores de 0.9464 para precisión, 0.9310 para sensibilidad, 0.9630 para especificidad, 0.9469 para el índice de calidad, 0.9470 para el área bajo la curva (AUC) y 0.9474 para el F-score. El modelo fue capaz de reconocer nueve de cada diez granos de maíz libres de gorgojos utilizando un número mínimo de muestras de entrenamiento. Estos resultados demuestran la eficacia del modelo en la detección precisa de la infestación por gorgojos en los granos de maíz. La capacidad del modelo para identificar con precisión los granos afectados por gorgojos es crucial para tomar medidas rápidas y controlar la propagación de la plaga, lo que puede prevenir pérdidas económicas considerables y preservar la calidad del maíz almacenado. La investigación sugiere que el uso de ResNet-50, ofrece una solución eficiente y de bajo costo para la detección temprana de la infestación por gorgojos en los granos de maíz. Estos modelos pueden procesar rápidamente grandes cantidades de datos de imágenes y realizar análisis precisos, lo que facilita la identificación de granos afectados.<hr/>Abstract The article explores the use of convolutional neural networks, specifically ResNet-50, to detect weevils in corn kernels. Weevils are a major pest of stored maize and can cause significant yield and quality losses. The study found that the ResNet-50 model was able to distinguish with high precision between weevil-infested corn kernels and healthy kernels, achieving values ​​of 0.9464 for precision, 0.9310 for sensitivity, 0.9630 for specificity, 0.9469 for quality index, 0.9470 for the area under the curve (AUC) and 0.9474 for the F-score. The model was able to recognize nine out of ten weevil-free corn kernels using a minimal number of training samples. These results demonstrate the efficiency of the model in the accurate detection of weevil infestation in maize grains. The model's ability to accurately identify weevil-affected grains is critical to taking rapid action to control the spread of the pest, which can prevent significant economic losses and preserve the quality of stored corn. Research suggests that the use of ResNet-50 offers an efficient and low-cost solution for the early detection of weevil infestation in corn kernels. These models can quickly process large amounts of imaging data and perform accurate analysis, making it easy to identify affected grains. <![CDATA[Enfermedades que afectan el cultivo de café: Elucidando el ciclo de vida de Roya, Mal de Hilachas y Cercosporiosis]]> Resumen El café (Coffea spp.) es el segundo producto básico de mayor importancia a nivel mundial, siendo C. arabica su especie más representativa. El cultivo de café es afectado por diferentes enfermedades fúngicas que reducen el área fotosintéticamente activa de sus hojas y la producción de granos. Por orden de importancia se destacan la Roya causada por el patógeno biótrofo Hemileia vastatrix que es de difícil manejo por su tipo de reproducción. Otra no menos importante, el Mal de hilachas ocasionada por los basidiomicetos Ceratobasidium noxium (Sin. Corticium koleroga) y C. chavesanum, que afectan todos los tejidos aéreos de las plantas. La tercera enfermedad, la Cercosporiosis causada por Cercospora coffeicola infecta tanto hojas como granos lo que dificulta su manejo. Aunque hay basta información científica sobre la Roya, muy poco se conoce sobre la etiología, sintomatología, ciclo de vida y manejo de Mal de hilachas y Cercosporiosis. Se utilizaron fotografías y micrografías de alta resolución y se las relacionó con la información científica disponible. Además, se recopiló información científica actualizada sobre cada enfermedad, y con eso se elaboraron los ciclos de vida. Así mismo, en este manuscrito se describe el manejo de las tres enfermedades basado principalmente en el uso de medidas genéticas, culturales, físicas, biológicas y químicas, y su integración como una alternativa sostenible en el agroecosistema de café. Entre los principales desafíos actuales y futuros en café están la evaluación de cultivares, diversidad genética de Ceratobasidium spp. y C. coffeicola, interacciones planta-patógenos, y prácticas de manejo agroecológicas.<hr/>Abstract Coffee (Coffea spp.) is the second most significant commodity worldwide, with C. arabica being its most representative species. The coffee crop is affected by different fungal diseases that reduce the photosynthetically active area of its leaves and the production of grains. In order of agronomic importance, the rust caused by the biotrophic pathogen Hemileia vastatrix is a disease difficult to manage due to its type of reproduction. Another no less important, Thread Blight, caused by the basidiomycetes Ceratobasidium noxium (Syn. Corticium koleroga) and C. chavesanum, affects all aerial tissues of plants. The third disease, Cercospora leaf spot caused by Cercospora coffeicola, infects both leaves and grains, making it difficult to manage. Although there is enough scientific information on Rust, very little is known about the etiology, symptomatology, life cycle, and management of Thread Blight and Cercospora leaf spot. High-resolution photographs and micrographs were used and related with available scientific information. In addition, current scientific information on each disease was compiled, and with that, the life cycles were developed. Likewise, this manuscript describes the management of the three diseases based mainly on the use of genetic, cultural, physical, biological, and chemical measures and their integration as a sustainable alternative in the coffee agroecosystem. Current and future challenges in coffee include the evaluation of cultivars, genetic diversity of Ceratobasidium spp. and C. coffeicola, plant-pathogen interactions, and agroecological management practices.