Artículos científicos

URI permanente para esta colecciónhttps://repositorio.inia.gob.pe/handle/20.500.12955/8

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Climate change and tree cover loss affect the habitat suitability of Cedrela angustifolia evaluating climate vulnerability and conservation in Andean montane forests
(PeerJ Inc., 2025-02-27) Ames Martínez, Fressia N.; Capcha Romero, Ivan; Guerra, Anthony; Inga Guillen, Janet Gaby; Quispe Melgar, Harold Rusbelth; Galeano, Esteban; Rodríguez Ramírez, Ernesto C
Background. Because of illegal logging, habitat fragmentation, and high value timber Andean montane forest Cedrela species (such as Cedrela angustifolia), is endangered in Central and South America. Studying the effects of climate change and tree cover loss on the distribution of C. angustifolia will help us to understand the climatic and ecological sensitivity of this species and suggest conservation and restoration strategies. Methods. Using ecological niche modeling with two algorithms (maximum entropy (MaxEnt) and Random Forest) under the ecological niche conservatism approach, we generated 16,920 models with different combinations of variables and parameters. We identified suitable areas for C. angustifolia trees under present and future climate scenarios (2040, 2070, and 2100 with SSP 3-7.0 and SSP 5-8.5), tree cover loss, and variables linked to soil and topography. Results. Our results demonstrated 10 environmental variables with high percentage contributions and permutation importance; for example, precipitation seasonality exhibited the highest contribution to the current and future distribution of Cedrela angustifolia. The potential present distribution was estimated as 13,080 km2 with tree cover loss and 16,148.5 km2 without tree cover loss. From 2040 to 2100 the species distribution will decrease (from 22.16% to 36.88% with tree cover loss variation). The results indicated that Bolivia displayed higher habitat suitability than Ecuador, Peru, and Argentina. Finally, we recommend developing conservation management strategies that consider both protected and unprotected areas as well as the impact of land-use changes to improve the persistence of C. angustifolia in the future.
Fusarium ear rot and how to screen for resistance in open pollinated maize in the Andean regions
(Springer Nature, 2006-10-13) Silva, E.; Mora, E.A.; Medina Hoyos, Alicia Elizabeth; Vasquez, J.; Valdez, D.; Danial, D. L.; Parlevliet, J. E.
Ears infected with ear rot were collected from five provinces in Ecuador. Of the 44 samples analysed 26 carried Fusarium verticillioides, 11 F. subglutinans, two F. graminearum and five carried fungi different from Fusarium. The pathogenicity of ten isolates, seven of F. verticillioides and three of F. subglutinans, were tested. Per isolate 30 ears of the susceptible cultivar Mishca were inoculated by pricking a steel pin, dipped into a spore suspension, through the husks in the central part of the ear 14 days after mid-silk. Ears inoculated with sterile water and ears without any treatment, natural infection, served as controls. The disease severity (DS) of the ears ranged from 14 to 58% ear rot, the range being similar for both species. The DS of the water control, 19%, was much higher than that of the natural control of 2%. Five strains gave a DS of over 40%, significantly higher than the water control. The DS of the others were similar to the water control. In a series of experiments the effect of various methods of applying Fusarium spores through the husks into young ears were compared. All tested methods resulted in DSs significantly higher than those of the two controls. Inoculation with tooth picks and steel pins dipped in a spore suspension gave similar ear rot percentages. Inoculations at 7 to 14 days after mid-silk produced the highest DS’s. There was no significant effect of spore concentration on the DS. Cultivars differed considerably, the range being from around 20% to over 50%. Surprisingly, only wounding the husks, the sterile water control, resulted in a fairly high DS, much higher than that of the natural control. As the ranking order of the cultivars after wounding only and after inoculation did not seem to be different from the ranking order of the natural control it is suggested to use in areas with high inoculum pressures like the Andes only wounding by means of a steel pin for screening for resistance to maize ear rot.
Comprehensive characterization of raw and processed quinoa from conventional and organic farming by label free shotgun proteomics
(American Chemical Society (ACS), 2025-01-16) Galindo Luján, Rocío; Pont, Laura; Minic, Zoran; Berezowski , Maxim V.; Quispe Jacobo, Fredy Enrique; Sanz Nebot, Victoria; Benavente, Fernando
Quinoa is widely recognized for its exceptional nutritional properties, particularly its complete protein content. This study, for the first time, investigates the effects of processing methods (boiling and extrusion) and farming conditions (conventional and organic) on the proteomic profile. Following a label-free shotgun proteomics approach, a total of 1796 proteins were identified and quantified across all quinoa samples. Regarding processing, both boiling and extrusion produced protein extracts with lower total protein content, with the number of identified proteins decreasing from 1695 in raw quinoa to 957 in processed quinoa. Boiling led to a reduction in protein diversity and expression, while extrusion, which involves high temperatures and pressures, specifically decreased the abundance of high molecular mass proteins. Concerning cultivation practices, organic farming was associated with a broader protein diversity, especially proteins related to translation (28 vs 5%), while conventional farming showed a higher abundance of catalytic and enzymatic proteins (67 vs 46%). These findings highlight the distinct proteomic changes induced by different processing methods and farming conditions, offering valuable insights to manage quinoa’s nutritional, bioactive, and functional properties across various production practices.
Influence of agroclimatic factors on the efficiency of multi-ovulation in cattle in the Peruvian tropics
(Frontiers Media S.A., 2025-04-01) Segura Portocarrero, Gleni Tatiana; Murga Valderrama, Nilton Luis; Lopez Lapa, Rainer Marco; Saucedo Uriarte, José Américo; Gongora Bardales, Deiner Jhonel; Frias Torres, Hugo; Poclín Rojas, Annie Yoselin; Depaz Hizo, Benjamin; Vasquez Tarrillo, Ronald Will; Heredia Vilchez, Lizeth Amparo; Ampuero Trigoso, Gustavo
Introduction: Agroclimatic conditions are key determinants in the development of animal production and reproduction, with specific breed differences in vulnerability to environmental stress. This research aims to determine the influence of agroclimatic factors on the efficiency of multi-ovulation in cattle in the Peruvian tropics. Methods: The study was conducted at the “El Porvenir” Agricultural Experimental Station (EEA) of the National Institute of Agricultural Innovation (INIA), located in the district of Juan Guerra, province and department of San Martín, Peru. Throughout a year, four collections of structures were made from 12 Bos indicus donor cows from the genetic nucleus of the PROMEG Tropical project every 2 months under intensive breeding conditions. The cows were classified according to their production: milk (five individuals of the Gyr breed and two of the Guzerat breed) and meat (two individuals of the Nelore breed and three of the Brahman breed), with ages of 3 and 4 years, selected based on specific criteria: regular estrous cycles, no deformities or reproductive problems, and certified pedigree registration. During each collection protocol, the number of viable structures (blastocysts and morulas), non-viable structures (unfertilized oocytes-UFO and degenerated), and agroclimatic factors [temperature (°C), relative humidity (%), precipitation (mm), wind speed (m/s), and the Temperature-Humidity Index (THI)] were evaluated at three times (6 a.m., 1 p.m., and 6 p.m.). A longitudinal experimental design was used for the analysis. Statistical tests were applied, including ANOVA and post-hoc tests (Tukey's Test), to assess the significance of differences between variables, such as the humidity index and temperature in relation to the production of viable structures and non-viable structures. Data visualization was achieved using R Studio libraries, including ggplot2, factoextra, and FactoMineR. Results: The analyses highlight the influence of the interaction between humidity and temperature, resulting in THI on bovine stress, revealing complex interactions that primarily affect embryo production. Stress peaks, especially under adverse conditions, were observed to significantly impact animal health. Discussion: This response to stress can affect both overall well-being and productive performance. Additionally, it should be noted that this impact varies according to the adaptability and resilience of the breed. Therefore, it is suggested to continue this study, as the literature on this topic is limited, and to conduct further research to optimize the well-being and productivity of livestock.
Productive and culinary characteristics of four cultivars of the popping bean (Phaseolus vulgaris L.), Canaán, 2735 meters above sea level. Ayacucho, 2022.
(Editorial MQR, 2025-03-21) Zambrano Ochoa , Lurquín Marino; Aramburo Pretel, Jean Marco; Altamirano Pérez, Ana María
Introducción. El frijol reventón originario de la parte central de los Andes constituye un alimento principal en la dieta de las comunidades rurales por su alto valor nutricional. Objetivo. Analizar las características productivas y culinarias de cuatro cultivares de frijol reventón, cultivados en las condiciones de Canaán, a 2735 msnm, en Ayacucho, durante el año 2022. Método. Se realizó un estudio experimental aplicando el Diseño Bloques Completo Randomizados con 4 variedades de frijol reventón tipo IV y un testigo tipo I arbustivo. El experimento se llevó a cabo con 3 repeticiones, sumando un total de 15 unidades experimentales. Se analizó variables de respuesta como la precocidad del cultivo, la productividad y la calidad del grano tostado. Resultados. El cultivar CFA-007 alcanzó la madurez fisiológica a los 193 días, seguido por las variedades CFA-012, CFA-005 y CFA-016. En cuanto a la altura de planta, el cultivar CFA-026 destacó con 237.93 centímetros, sin presentar diferencias significativas respecto a los demás cultivares. En términos de productividad, el CFA-007 alcanzó un rendimiento de 5700 kilogramos por hectárea, mientras que el CFA-005 obtuvo 4623 kilogramos por hectárea. En lo que respecta a la calidad del grano tostado, el índice de expansión del grano del cultivar CFA-026 fue del 80%, seguido por los cultivares CFA-007, CFA-005 y CFA-012. Conclusión. Tanto las condiciones ambientales de la zona donde se desarrolló el experimento como el manejo agronómico fueron oportunas para el crecimiento y desarrollo de los cultivares.
Taxonomy and new collections of wild potato species in Central and Southern Peru in 1999
(Springer Nature, 2001-05-31) Salas, Alberto R.; Huamán, Zósimo; Hijmans, Robert J.; Torres Maita, Rafael Vinci; Hoesktra, Roel; Schüler, Konrad
Peru contains about half of the described wild potato taxa, and many of these are not yet preserved in genebanks. This paper reports results of the second of a series of five planned collecting expeditions to Peru. Collections were made in the central Peruvian departments of Ancash, Huancavelica, La Libertad, and Lima, from March 8 to April 25,1999. They follow collections in 1998 in the southern Peruvian departments of Apurimac, Arequipa, Cusco, Moquegua, Puno, and Tacna. We collected 101 germplasm accessions, including first germplasm collections of the following 22Solanum taxa:Solanum amayanum, S. anamatophilum, S. arahuayum (lost in germplasm increase),S. augustii, S. bill- hookeri, S. cantense, S. chavinense, S. chomatophilum var. subnivale, S. chrysoflorum, S. gracilifrons, S. hapalos um, S. huarochiriense, S. hypacrarthrum, S.jalcae, S. moniliforme, S. multiinterruptum f. longipilosum, S. multiinterruptum var. machaytambinum, S. peloquinianum, S. rhombilanceolatum, S. simplicissimum, S. taulisense (lost in germplasm increase), andS. wittmackii. In addition, new collections were made of the under-collected speciesS. hastiforme (three collections). The above taxonomy is that used in planning our expedition, that we compare to a new treatment of Peruvian wild potatoes published by C. Ochoa in 1999. This paper reports the collection and new species identifications of the 1999 collections, and germplasm conservation and survival of the 1998 and 1999 collections. In addition, chromosome counts are provided for 134 accessions from the 1998 and 1999 expeditions, including first reports forS. chomatophilum var. subnivale (2n = 2x = 24),S. megistacrolobum subsp.purpureum (2n = 2x = 24), andS. multiinterruptum var.multiinterruptum f.albiflorum (2n = 2x = 24); we also report the first triploid count of an accession ofS. immite.
Aislamiento e identificación molecular de cepas bacterianas anaeróbicas aisladas del compartimento 1 de la alpaca (Vicugna pacos)
(Universidad Nacional Mayor de San Marcos, 2025-02-28) Coila, Pedro; Romero Ávila, Yolanda Madelein; Sánchez, Diana; Oros, Oscar; Zapata, Celso; Flores, Nils; Estrada Cañari, Richard
El estudio tuvo como objetivo identificar bacterias anaeróbicas aisladas del compartimento 1 del tracto digestivo de las alpacas. Se obtuvieron 4 aislamientos del licor (LC1) y 9 de la pared del compartimento (PC1) de los tractos digestivos. Los aislamientos de LC1 se cultivaron en agar Anaeróbico de Brewer (BA), y los aislamientos de PC1 en BA suplementado con L-cisteína. Los aislamientos anaeróbicos fueron sometidos a identificación mediante observación microscópica y pruebas bioquímicas, seguidas de la extracción de ADN bacteriano total. La amplificación se realizó utilizando cebadores 27F-1492R en el gen 16S ARNr, y se secuenció utilizando el método Sanger con un analizador de ADN ABI PRISM 3730XL. El análisis bioinformático reveló que las cepas correspondientes a la especie de LC1 eran cuatro Streptococcus equinus y de PC1 eran nueve Streptococcus vicugnae. En el análisis filogenético, las cepas de Streptococcus equinus formaron un clado monofilético con un valor de Bootstrap de 100 y Streptococcus vicugnae con 88. Las cepas revelaron una naturaleza estrictamente anaeróbica, destacando la complejidad de la taxonomía del género Streptococcus y enfatizando la necesidad de futuras investigaciones para aclarar su clasificación taxonómica
Especies del género Abuta (Anomospermeae, Menispermaceae) del Perú
(Universidad Nacional Mayor de San Marcos, Facultad de Ciencias Biológicas, 2025-03-15) Ortiz, Rosa del C.; Zañartu Flores, Ricardo A.; Rodríguez del Castillo, Ángel M.; Amasifuen Guerra, Carlos Alberto
El género Abuta constituye el segundo taxón más diverso dentro de las Menispermaceae neotropicales. La presente investigación documenta las 12 especies registradas en territorio peruano, proporcionando una caracterización morfológica detallada de cada taxón, sintetizada en una clave dicotómica para su identificación. Se presenta documentación fotográfica de especímenes, tanto in situ como preservados en herbario, para todas las especies excepto A. aristeguietae. Adicionalmente, se analiza la distribución geográfica de cada especie, tanto a nivel nacional como global. Es importante señalar que la limitada disponibilidad de especímenes fértiles, frecuentemente restringidos a un solo sexo (ya sea ejemplares estaminados o pistilados), ha representado un desafío significativo para el análisis comparativo interespecífico. Abuta grandifolia destaca como la especie de mayor distribución y frecuencia de colecta; sin embargo, investigaciones recientes sugieren que este taxón comprende un complejo de entidades cuyas delimitaciones taxonómicas requieren mayor estudio.
Gastrointestinal parasites in free grazing goats from Ayacucho, Peru: prevalence and risk factors associated with infection in herds
(Springer Science and Business Media B.V., 2024-10-29) Palomino Guerrera, Walter; Ramos Huaman, Michael; Flores Prado, Vania; Godoy Padilla, David; Zárate Rendón, Daniel
This study assessed the prevalence and risk factors associated with gastrointestinal parasite infection in goats in Ayacucho, Peru. Fecal samples were collected from a total of 254 goats from four districts of Ayacucho: Ocaña (89), Colca (76), Pacaicasa (64), and Luricocha (25) during the dry season; recording the location, sex, and age of the animals. The fecal samples were analyzed using the flotation technique in salt and sugar solution, and modified McMaster egg counting techniques for eggs/oocysts (epg/opg) of gastrointestinal parasites. The associations between location, sex, and age with the prevalence of gastrointestinal parasites were analyzed using the chi-square test. Fecal samples showed an overall parasite prevalence of 87.80%. The identified parasites were Eimeria spp. (86.22%), Strongyle type eggs (STE) (65.75%), Skrjabinema spp. (7.87%), Trichuris spp. (3.15%) and Moniezia spp. (3.15%). There was a significant association between the location and the presence of parasites (p<0.05); where STE was more prevalent in the district of Colca (98.68%); Trichuris spp. in Pacaycasa (9.38%); Skrjabinema spp. (48.00%), Moniezia spp. (12.00%) and Eimeria spp. (100%) were more prevalent in Luricocha. Sex had a significant association with the prevalence of Eimeria spp., Skrjabinema spp. and Moniezia spp. (p<0.05); while age had a significant association with parasitosis only for Trichuris spp. and Moniezia spp. (p<0.05). The epg/opg values revealed a higher parasite burden in goats from Colca compared to the other locations (p<0.05). There was also no statistical relationship between fecal egg/oocyst counts and sex or age, nevertheless, there were moderate and high parasitic burdens. The high prevalence of parasites such as nematodes, cestodes, and coccidia suggests the need to implement strategic control and prevention programs in free-grazing goats. Location and sex were the most relevant risk factors for parasitosis in Ayacucho, Peru.
Identification of the optimal substrate for sexual propagation of Cinchona officinalis l.: Implications for conservation and sustainable use
(Springer, 2025-03-19) Marcelo Bazán, Fátima Elizabeth; Mantilla Chávez, Walter; Paredes Pajares, Katia Patricia; Chávez Cercado, Deisy Medaly; Baselly Villanueva, Juan Rodrigo; Álvarez Álvarez, Pedro
Cinchona officinalis L., a tree species of medicinal, ecological and economic importance, inhabits one of the richest and most fragile ecosystems in the world (montane forests) where it contributes to water and climate regulation, erosion control and carbon sequestration. However, the species is subject to strong anthropogenic pressure and is currently endangered. Unfortunately, little is known about propagation and repopulation techniques or the substrate preferences of the species. We designed a randomised trial with four replications in which 12 trial substrates (peat mixed with sand, moss or pine sawdust and supplemented with chicken manure, guano, compost or agricultural soil) were evaluated to identify the optimal substrate for the sexual propagation of Cinchona officinalis seedlings. The physical and chemical properties of the substrates were analysed, and the impact of these on the emergence, biometry and quality of seedlings were evaluated. Statistical analysis was performed using Scott-Knott and Kruskal-Wallis tests (p<0.05), principal component analysis, heatmap analysis and correlation analysis. The substrate composed of peat, moss and agricultural soil (ratio, 2:2:0.5) was found to be optimal, consistently producing the highest emergence rates and superior biometrics and quality indices. These findings represent a remarkable advance in the propagation of C. officinalis and provide valuable insights enabling the vulnerability of this species to be addressed in ecosystems subject to anthropogenic pressures, thus ensuring the conservation and sustainable use of the species.
Palatosquisis en un ternero raza Holstein. Caso clínico
(División de Investigación, Facultad de Ciencias Veterinarias, Universidad del Zulia, 2024-11-03) Centellas Jáuregui, Rosita Valeria; Portal Torres, Jorge; Cueva Rodríguez, Medali; Alvarado , Wigoberto; Quilcate Pairazamán, Carlos Enrique
Palatoschisis is a hereditary teratoma that occurs in cattle, it is a hereditary anomaly that affects the oral cavity due to a bad closure during embryonic development, this malformation can have a negative impact on the animal, affecting its feeding and generating problems such as regurgitation and rhinitis. We report the case of a 2-month-old female bovine that presented a malformation specifically in the hard palate. It was observed that the calf presented palatoschisis, showed difficulty in feeding, as well as rhinitis, symptoms derived from the described anomaly.
Modeling growth curve parameters in Peruvian llamas using a Bayesian approach
(Elsevier, 2025-03-20) Canaza Cayo, Ali William; Mamani Cato, Rubén Herberth; Churata Huacani, Roxana; Rodríguez Huanca, Francisco Halley; Calsin Cari, Maribel; Huacani Pacori, Ferdeynand Marcos; Cardenas Minaya, Oscar Efrain; de Sousa Bueno Filho, Júlio Sílvio
The objective of this study was to fit four nonlinear models (Brody, von Bertalanffy, Gompertz and Logistic) to realizations of llama weight, using frequentist and Bayesian approaches. Animals from both sexes and types (K'ara and Ch'accu) were observed. Data consisted of 43,332 monthly body weight records, taken from birth to 12 months of age from 3611 llamas, collected from 1998 to 2017 in the Quimsachata Experimental Station of the Instituto Nacional de Innovación Agraria (INIA) in Peru. Parameters for Non-linear models for growth curves were estimated by frequentist and Bayesian procedures. The MCMC method using the Metropolis-Hastings algorithm with noninformative prior distributions was applied in the Bayesian approach. All non-linear functions closely fitted actual body weight measurements, while the Brody function provided the best fit in both frequentist and Bayesian approaches in describing the growth data of llamas. The analysis revealed that female llamas reached higher asymptotic weights than males, and K'ara-type llamas exhibited higher asymptotic weights compared to Ch'accu-type animals. The asymptotic body weight, estimated for all data using the Brody model, was 42 kg at 12 months of age in llamas from Peru. The results of this research highlight the potential of applying nonlinear functions to model the weight-age relationship in llamas using a Bayesian approach. However, limitations include the use of historical data, which may not fully represent current growth patterns, and the reliance on non-informative priors, which could be improved with prior knowledge. Future studies should refine these aspects.
Enteric methane emission factor for dairy farming in Peru
(MDPI, 2024-12-11) Fernandez, Melisa; Fuestes Navarro, Eduardo; Viera Valencia, Mario Agustín; Llacsa, Javier; Carrasco Chilón, William Leoncio; Altamirano, Wilman; Romero Delgado, Gelver; Ayala, Richard; Vela Alvarado, Jorge Washinton; Zegarra Paredes, Jorge Luis; Molina Botero, Isabel Cristina; Gómez, Carlos
The objective of this study was to determine the enteric methane (CH4) emission factor (EF) at the national level for Peruvian dairy cattle following the IPCC Tier II (2006, 2019) methodology. Data were collected from seven regions of Peru and classified according to the type of feeding as intensive, semi-intensive or extensive. It included farm information (geolocation) and livestock information for two seasons of the year. At the national level, lactating cows obtained the highest EF with 117 kg CH4/head/year, followed by heifers from 15 to 24 months of age (91 kg), non-lactating cows (74 kg), heifers from 12 to 15 months of age (67 kg), calves (62 kg) and pre-weaned calves (16 kg). Additionally, the highest EF was reported for lactating cows in the intensive system (151.8 kg CH4/head), which is 46.8 kg CH4/head more per year than that reported in the semi-intensive and extensive systems in the same animal category. The combined uncertainty in all animal categories was low to very low (between 9.4 and 18.72%), except for that of lactating cows, which was low to medium (22.24 and 26.72%). These results allowed us to find the EF that exerts the most pressure according to the level of intensity in Peruvian dairy farming.
Impact of production practices and sanitary management on the prevalence of Neospora caninum and bluetongue virus in Creole goats from the tropical dry forest of Utcubamba, Peru
(American Veterinary Medical Association, 2024-11-04) Tafur Gutierrez, Lucinda; Alva, Gudelio; Godoy Padilla, David J; Frias, Hugo; Arista, Miguel A; Bardales, William; Encina, Ricardo; Portocarrero, Segundo M; Saucedo, José A; Cruz Luis, Juancarlos Alejandro; Murga, Nilton L.
OBJECTIVE This study aimed to report the impact of production practices and sanitary management on the prevalence of Neospora caninum (N caninum) and bluetongue virus (BTV) in Creole goats from the tropical dry forest of Utcubamba, Peru. METHODS 354 blood samples were obtained from male and female goats of diverse ages reared under an extensive productive system. The diagnosis of N caninum and BTV was conducted through a commercial ELISA kit (iD.vet) with readings taken on a Bio-Rad iMark microplate reader at 450 nm. Additionally, a survey was conducted with 18 goat producers to categorize them based on social, technical (production, health, reproduction, nutrition, and infrastructure), environmental, and economic factors. RESULTS The overall seroprevalence of N caninum and BTV in goats was 6.21% and 7.06%, respectively, Notably, group II farmers had the highest prevalence rates at 7.69% for N caninum and 23.08% for BTV. This group comprises producers with fewer than 21 goats, while group III includes 14.3% of producers with over 60 goats and better infrastructure. CONCLUSIONS This study confirms the presence of N caninum and BTV in goats of Utcubamba, Peru. Group II displayed the highest prevalence rates, suggesting that herd size and management infrastructure influence disease prevalence. CLINICAL RELEVANCE In the tropical dry forest of Utcubamba, inadequate management of N caninum carrier agents (eg, nondewormed dogs) heightens transmission risk, while the tropical climate supports BTV vectors. Effective diagnosis and health management strategies, including vector control and biosecurity practices, are crucial for ongoing herd health monitoring
Carbon reserves in coffee agroforestry in the Peruvian Amazon
(Frontiers, 2024-12-11) Vallejos Torres, Geomar; Gaona Jimenez, Nery; Pichis García, Roger; Ordoñez, Luis; García Gonzales, Patricia; Quinteros , Aníbal; Lozano, Andi; Saavedra Ramírez, Jorge; Tuesta Hidalgo, Juan C; Reategui, Keneth; Macedo Cordova, Wilder; Baselly Villanueva, Juan Rodrigo; Marín, César
Secondary forests and coffee cultivation systems with shade trees might have great potential for carbon sequestration as a means of climate change adaptation and mitigation. This study aimed to measure carbon stocks in coffee plantations under different managements and secondary forest systems in the Peruvian Amazon rainforest (San Martín Region).
Descripción ósea y relación de la pelvimetría con la biometría corporal en alpacas (Vicugna pacos)
(Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, 2024-10-31) Pacheco, Joel Ivan; Chacón, Yemíra; Zea, José; Calsin, Bilo; Mamani, Godofredo; Mamani Cato, Rubén Herberht
El objetivo del estudio fue describir la cintura pélvica, la pelvimetría y su relación con la biometría en alpacas. Para la descripción ósea se utilizaron cuatro piezas pélvicas de alpaca hembra. Además, se utilizaron a 72 hembras destinadas a faenamiento (subdivididas en tres grupos etarios de 4, 5 y 6 años) para tomar las medidas pelvimétricas internas (diámetro sacro-púbico, diámetro bis-iliaco superior, diámetro bis-iliaco inferior y diámetro bis-iliaco medial) y distancias pélvicas externas (distancia inter iliaca, distancia interisquiática y distancia ílio-isquiática); además, se tomaron tres medidas biométricas (altura a la cruz, largo del cuerpo y diámetro abdominal). La descripción ósea de las pelvis demuestra la presencia del hueso inter-isquiático, y el piso pélvico de forma ligeramente cóncava, lo cual incrementa el área pélvica. La pelvimetría interna demuestra la forma ovalada de la circunferencia pélvica, siendo más alta que ancha, de tipo dolicopélvica. Externamente, la pelvis presenta una forma cónica ubicada cráneo caudalmente. La correlación más alta se determinó entre la cavidad y el área pélvica, con un coeficiente de determinación de 82.92%.
Effectiveness of protected areas in containing the loss of Peruvian Amazonian forests
(Elsevier, 2025-01-11) Rojas Briceño, Nilton B.; Cajas Bravo, Verónica; Pasquel Cajas, Alexander; Guzman Valqui, Betty Karina; Silva López, Jhonsy O.; Veneros, Jaris; García, Ligia
Peruvian Amazonian Forests (PAF), vital for biodiversity, climate, and human well-being, lost 2.92M ha during 2001-2022, mainly due to anthropogenic activities. This prompted strategies to conserve and protect the PAF, such as land use and natural resource restrictions, with natural protected areas (NPAs) being the main strategy. This study evaluated the effectiveness of 41 NPAs in containing deforestation in the PAF by analyzing national spatial data. An Effectiveness Index (EI) was constructed by adding five standardized parameters: (1) the percentage of deforested area (DA%) and (2) its annual rate of change (DAr) between 2000 and 2022 inside each NPA, (3) the difference in DAr between NPAs and their surrounding areas, (4) their corresponding ecoregions, and (5) the entire PAF. In 2000, the DA% was 7.15% of the PAF, increasing to 10.88% in 2022. NPAs showed lower DAr than their surrounding areas and ecoregions, except for five NPAs. Of the 41 NPAs, nine were non-effective (EI≤3), 31 moderately effective (3
Low seed viability and germination in Polylepis flavipila hinder forest restoration: The role of seed mass and maternal effects
(Elsevier B.V., 2024-12-05) Huayta-Hinojosa, L. David; Quispe-Melgar, Harold Rusbelth; Lagones Poma, Katherine Lucero; Llacua-Tineo, Yashira Stefani; Ames-Martínez, Fressia Nathalie; Renison, Daniel
Seed physiological quality is usually determined by the interaction between genetics and the mother tree’s environment, as well as by intrinsic characteristics, such as seed mass. In the Andean highlands, massive sapling production for forest restoration projects is constrained by seed availability and quality. There, species of the genus Polylepis dominate the remnant forests. The associations of seed viability with seed mass and maternal effects were evaluated in P. flavipila, a threatened tree species endemic to the Peruvian Andes. The characteristics and environments of 18 mother trees from two sites were measured, and seed quality was assessed in three tests. Seed mass was 3.49 ± 1.76 mg (range: 0.5–16 mg) and showed the greatest variability within mother trees, followed by variability among trees and among sites. Viability rates, standard germination and greenhouse germination (2.06 ± 1.35 %, 0.59 ± 0.89 % and 0.64 ± 1.11 %; respectively) were low at both sites. These results were attributed to the presence of seeds with non-viable or absent embryos. Seed viability increased with seed mass and mother tree height, and was positively associated with number of seedlings (r = 0.56). The deficient seed viability and germination found in P. flavipila are the lowest reported for the genus. The low seed physiological quality detected is a risk factor that exacerbates the species’ degree of threat, posing a challenge for sapling production. The reported associations of P. flavipila seed viability with seed mass and maternal char acteristics and environment may guide the selection of better seed quality and serve as a basis for future studies on the challenges and limitations of the reproductive biology of this species
A Comparison of Classification Algorithms for Predicting Distinctive Characteristics in Fine Aroma Cocoa Flowers Using WEKA Modeler
(2024-09-24) Tineo Flores, Daniel; Murillo, Yuriko S.; Marin, Mercedes; Gomez Fernandez, Darwin; Taboada, Víctor H.; Goñas Goñas, Malluri; Quiñonez Huatangari, Lenin
The expression of crop functional traits is influenced by environmental and management conditions, which in turn is reflected in genetic diversity. This study employed a data mining approach to determine the functional traits of flowers that influence cocoa diversity. A total of 1,140 flowers from 228 trees were utilized in this study, with 177 representing fine aroma cocoa trees and 51 trees belonging to other commercial cultivars. Three attribute evaluators (InfoGainAttributeEval, CorrelationAttributeEval and GainRatioAttributeEval), and six algorithms (Naive Bayes, Multinomial Logistic Regression, J48, Random Forest, LTM and Simple Logistic) were employed in this study. The findings indicated that the GainRatioAttributeEval attribute generator was the most efficacious in discerning the functional trait in cocoa diversity flowers. The algorithms Simple Logistic and LMT were the most accurate and specific, while Naive Bayes was the most efficient in terms of computational complexity for model building. This research provides a comprehensive overview of the use of machine learning to analyze functional traits of flowers that most influence cocoa genetic diversity. It also highlights the need to further improve these models by integrating additional techniques to increase their efficiency and extend the data mining approach to other agricultural sectors.
Aqueous-Medium Arsenic(V) Removal Using Iron Oxide-Coated Ignimbrite
(MDPI, 2024-12-28) Velarde Apaza, Lelie Diana; Chávez Collantes, Azucena; Solorzano Acosta, Richard; Cuevas Gimenez, Juan Pablo; Villanueva Salas, José Antonio
Arsenate As(V) is a toxic contaminant commonly found in aquifers and groundwater that poses significant risks to human health. The effective treatment of arseniccontaminated water is therefore crucial for safeguarding public health. This study investigates removing As(V) using iron oxide-coated ignimbrite in batch experiments by varying the adsorbent dosage, initial As(V) concentration, contact time, and system temperature. The adsorption experiments revealed that the Langmuir isotherm model better fit the data (R2 = 0.99) than the Freundlich model (R2 = 0.73). According to the Langmuir model, the maximum adsorption capacity of As(V) on the iron oxide-coated ignimbrite was 4.84 mg·g −1 ± 0.12 mg·g −1 of As(V), with a standard deviation of ±0.05 mg·g −1 after 2 h of exposure with 0.15 g/50 mL iron oxide-coated ignimbrite adsorbent concentration. In the kinetic analysis, the pseudo-first-order model best described the adsorption process at 283 K, 293 K, and 303 K, although the pseudo-second-order model also showed an adequate fit, particularly at 293 K. This indicates that, while the pseudo-first-order model is generally more suitable under these conditions, the pseudo-second-order model may also apply under certain circumstances. The results of the batch experiments demonstrate that iron oxide-coated ignimbrite is a promising adsorbent for effectively reducing high concentrations of As(V) in contaminated water

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