Chilean Journal of Agricultural & Animal Sciences

Reconocimiento a revisores 2023

Chileanjaas — vie, 29 dic 2023 00:00:00 -0500

PERFORMANCE OF BLACK PEPPER CUTTINGS AS INFLUENCED BY GROWING MEDIA

Tajudeen Bamidele Akinrinola, Rachael Abidemi Onadeko — vie, 29 dic 2023 00:00:00 -0500

Black pepper is a highly valued spice and an important ingredient in traditional medicine. The increase in black pepper cultivation to improve farmers’ income in Nigeria is constrained by poor seedling survival from vine cuttings. Using imported media to reduce mortality is expensive for low- ncome farmers. The objective of this study was to evaluate the influence of local growing media (topsoil, sawdust, and fresh rice hull) on the establishment and growth of black pepper vine cuttings in the nursery under screenhouse conditions. A repeated pot experiment was conducted using a randomised completed block design, with 9 treatments and four replicates. The following treatments were used: 100% topsoil (T1), 100% sawdust (T2), 100% rice hull (T3), 50% topsoil+50% sawdust (T4), 50% topsoil+50% rice hull (T5), 75% topsoil+25% sawdust (T6), 25% topsoil+75% sawdust (T7), 75% topsoil+25% rice hull (T8), and 75% rice hull +25% topsoil (T9). Data on sprouting, mortality and growth were evaluated. The results showed that T2 and T4 significantly reduced the number of days to sprouting compared to T1, T5 and T9, while T6, T7 and T8 exhibited a similar behaviour in the two plantings. Vine mortality was significantly higher in T3 compared to the other treatments, except for T5 and T8 in the second planting. With respect to number of leaves and leaf area, T2 and T6 showed significantly higher values at 8 and 12 weeks after planting (WAP), respectively; whereas T1 had significantly higher values at 16 and 20 WAP compared to the other treatments in both plantings. The results indicated that the most appropriate growing media for early transplanting are 100% sawdust and 50% topsoil+50% sawdust, while 100% topsoil is the most suitable for delayed transplanting.

PRE-HARVEST DESICCATION FOR PRODUCING HIGH QUALITY COWPEA SEEDS

Mariana Zampar Toledo, Gessí Ceccon — vie, 29 dic 2023 00:00:00 -0500

Pre-harvest desiccation of indeterminate growth habit plants such as cowpea may improve harvest efficiency, uniform maturation and seed quality. This research aimed to determine the effects of pre-harvest desiccation and harvesting time on the yield and quality of cowpea seeds. Two experiments were carried out in Dourados, State of Mato Grosso do Sul, Brazil, in the 2015 and 2017 growing seasons. The experimental design was a split-plot, with main plots arranged as a randomized complete block design, with four replications. Main plots corresponded to the application or no application of paraquat at physiological maturity and subplots to harvesting times: 0, 3, 6. 9, 12 and 15 days after that stage. Moisture content, weight and yield were assessed for each treatment. Physiological quality was evaluated by germination and vigor tests. Means of desiccation conditions were compared by the Tukey test (p?0.05) and harvest times by regression analysis, arranged as a 2x6 factorial. Seed yield and weight were negatively influenced by pre-harvest desiccation with paraquat and delayed harvest. Isolated and interactive responses for desiccation treatments and harvesting time on seed quality varied depending on the growing season. Seed germination and vigor were decreased by late harvest, while desiccation effects varied depending on harvest time.

PRE-TREATMENTS AND DRYING METHODS ON THE PHYSICOCHEMICAL AND SENSORY CHARACTERISTICS OF WILD MUSHROOMS (Suillus luteus) FROM APURIMAC-PERU

vie, 29 dic 2023 00:00:00 -0500

The objective of this research was to evaluate the effect of pre-treatments and drying methods on the physicochemical and sensory characteristics of edible wild mushrooms, Suillus luteus, collected in the pine forests of the Apurimac region, Peru. Two immersion pre-treatments were used: 5% lemon juice and 6% vinegar. Mushroom caps were cut into 3-cm thick slices, immersed at a ratio of 1:5 (w/v), and subsequently dried by direct solar drying and indirect solar drying using a fitotoldo (shade cover). The proximate composition, rehydration, color, total polyphenol content (TPC), antioxidant capacity (DPPH capacity), and sensory evaluation were determined for each sample. The results showed significant differences (p<0.05) between the treatments. Higher rehydration rates were observed in the samples subjected to direct solar drying and fitotoldo drying without pre-treatment, as well as those treated with vinegar. Regarding color, luminosity (L*) significantly decreased in the dried samples compared to the fresh sample. In the proximate analysis, the untreated samples had protein, crude fiber, and ash contents of 23.67 g/100 g, 11.10 g/100 g, and 5.59 g/100 g, respectively. Free-nitrogen extract (FNE) content increased to 47.13 g/100 g as mushrooms lost water. TPC and antioxidant capacity decreased significantly in the dried samples, but the pre-treated samples with vinegar recorded higher values of 8.38 mg GAE/g and 54.13 µmol TE/g, respectively. In the sensory evaluation, the samples pre-treated with vinegar had higher color, texture, and acceptability scores. Thus, the use of a fitotoldo without pre-treatment and with vinegar pre-treatment is the most efficient method for drying Suillus luteus mushrooms.

Amaranthus hybridus L. RESISTANT TO GLYPHOSATE AND CHLORIMURON IN PARAGUAY

vie, 29 dic 2023 00:00:00 -0500

Amaranthus species are extremely problematic weeds due to their aggressiveness and resistance, being Amaranthus palmeri S. Watson, Amaranthus retroflexus L., Amaranthus tuberculatus (Moq.) J. D. Sauer, and Amaranthus hybridus L. prominent worldwide. The present research aimed to study A. hybridus populations in Paraguay where the use of glyphosate and chlorimuron herbicides presented management challenges. This research was conducted in the municipalities of Corpus Christi and Hernandarias, Paraguay, in 2016, 2017, 2018, 2019, and 2020. Weed seeds with resistance indicators were collected, cultivated, and following a screening process, cultivated for seed production (heritability up to F₂), and the seeds were collected to obtain the herbicide dose-response curve. The herbicides glyphosate and chlorimuron were tested in portions of 1/8, 1/4, 1/2, 1, 2, 4, and 8 times the recommended dose on the package inserts (720 g acid equivalent [ae] ha^?1 and 20 g active ingredient [ai] ha^?1, respectively). Among the A. hybridus populations evaluated in Paraguay, biotype from Hernandarias with multiple resistance to ALS-inhibiting (HRAC 2) and EPSPs-inhibiting (HRAC 9) herbicides, and biotype from Corpus Christi with resistance to ALS-inhibiting herbicides (HRAC 2) were found. Therefore, rotation and combination of herbicides, as well as integration with non-chemical measures, are essential to control and prevent selection of resistant biotypes. Studies aimed to develop integrated weed management plans are essential for effective control. In countries like Paraguay, this becomes imperative because of the lack of research on this topic.

DYNAMICS OF CO2 EMISSION AND DISPERSION FROM TWO SUGARCANE MILLS IN THE GUAYAS BASIN

vie, 29 dic 2023 00:00:00 -0500

Sugarcane (Saccharum spp.) is a C4 plant widely cultivated for the production of sugar, energy, and other derivatives. Sugarcane fixes a certain amount of carbon in the biomass but emits variable amounts of carbon dioxide (CO₂₎ into the atmosphere, depending on the technologies used in both field and industrial processes. This study quantified and described the spatial and temporal dispersion of CO₂ emissions generated during the sugarcane harvest period by the San Carlos and Valdez sugarcane mills, in Guayas, Ecuador. Measurements of CO₂ were carried out using a 3M's portable gas analyzer model Monitor 3M-EVM-7, which provides digital readings without requiring any additional procedure. Samples were taken every two weeks during the milling period (June to December). Sampling was carried out at distances of approximately 280, 500, 1000, and 3000 m from the central chimney of the factories. Locations were eventually georeferenced to allow for possible associations to infer spatial and temporal patterns and distributions. The effects associated with dispersion patterns of greenhouse gases released from the industrial chimneys as well as wind direction and speed were considered. The results show that CO₂ emitted by the industrial sugarcane process did not impact surface-level measurements due to natural dispersion, although it decreased with distance. There was a high, negative, and significant correlation between CO₂ concentrations and temperature; and a high, direct, and significant correlation with dew point. CO₂ concentrations were inversely correlated with distances from the factory chimneys.

ESTIMACIÓN DE LA HUELLA DE CARBONO DE LAS GANADERÍAS DE LECHE DE LA ZONA ANDINA DEL ECUADOR

vie, 29 dic 2023 00:00:00 -0500

El sector lácteo es responsable de aproximadamente el 3,3% de las emisiones mundiales de gases de efecto invernadero (GEI), pero tiene potencial para desempeñar un papel importante en la mitigación del cambio climático mediante cambios en su gestión. Por ello, esta investigación tuvo como objetivo estimar las emisiones de GEI de las ganaderías de leche de dos provincias de la Sierra centro norte del Ecuador, por tipo y fuentes. La investigación se desarrolló en 24 ganaderías, agrupadas mediante un análisis de conglomerados en tres tipos (grandes, pequeñas y medianas), en función de sus características productivas. Para cuantificar y analizar las emisiones se utilizó el Programa Cool Farm Tool, y la información requerida se levantó mediante visitas en campo y entrevistas a los productores. Los resultados se analizaron de acuerdo con un diseño completamente al azar, mediante la prueba paramétrica de Fisher (p<0,05). Los resultados indican que la fermentación entérica es la mayor fuente de emisiones de GEI (5,27 Ton de CO₂-eq ha^-1 año^-1, 43,39%). Las ganaderías medianas emiten la mayor cantidad de emisiones por litro de leche producida (2,3 CO₂-eq L^-1 leche FPCM), siendo 50% y 84% mayores que aquellas producidas por ganaderías pequeñas y grandes, respectivamente. Se concluye que las ganaderías grandes son las más eficientes, mientras que las pequeñas son las más resilientes, ya que producen una menor cantidad de emisiones de GEI.

EFFECTS OF PLANT EXTRACTS ON IN-VITRO GAS PRODUCTION KINETICS AND RUMINAL FERMENTATION OF FOUR FIBROUS FEEDS: TOWARDS SUSTAINABLE ANIMAL DIETS

vie, 29 dic 2023 00:00:00 -0500

This study was conducted to determine the effects of increasing doses of plant extracts of moringa, thyme, and rosemary on in-vitro gas production (IVGP) of four fibrous feeds (kikuyu grass, alfalfa hay, oat hay, and corn stover). The extracts were applied at doses of: 0 (control), 6 (low), 12 (medium), and 18 (high) ml/g dry matter (DM). IVGP was assessed using three fistulated goats and different incubation periods. At the end of incubation, dry matter degradability (DMd), gas yield (GY24), metabolizable energy (ME), short chain fatty acids (SCFA), and microbial crude protein (MCP) production were determined. The results showed that the increasing doses of the evaluated extracts had neither linear nor quadratic effect on gas production (GP) of all fibrous feeds (P > 0.05). The addition of plant extracts increased GP at all incubation periods (P ? 0.05), being higher for thyme. Moringa, thyme, and rosemary extracts altered ruminal fermentation parameters, including ME, MCP, SCFA, the partitioning factor at 72 h of incubation (PF72), and DMd, being higher for thyme followed by rosemary and moringa. In conclusion, the addition of thyme extract increased GP, ME, MCP, SCFA, PF72, and DMd compared with rosemary and moringa plant extracts. However, additional in-vivo studies should be conducted to confirm these effects.

PRODUCTION AND ECONOMIC EVALUATION OF THE CORRIEDALE BREED AND CROSSES WITH DOHNE MERINO GENERATED DURING THE ESTABLISHMENT OF A ROTATIONAL CROSSBREEDING SCHEME: EWE HOGGET RESULTS

Washington Bell, Ana Laura Sánchez, Raúl Ponzoni — vie, 29 dic 2023 00:00:00 -0500

Corriedale (C) is the predominant sheep breed in Uruguay, but prices for its medium fineness wool have been low. Dohne Merino (DM) has attracted interest because it has similar attributes to C, but finer wool. We evaluated wool and body traits of crossbred ewe hoggets generated during the establishment of a rotational crossbreeding scheme between C and DM. The program started with 400 C ewes. The first year 100 C ewes were mated to C rams, and the rest were mated to DM. Purebred C progeny were always mated to C rams. The crossbred progeny was randomly divided into two equal groups, one of which was mated to C rams and the other to DM rams. Subsequent progenies were mated to rams of the opposite breed to its sire. Performance was recorded from 2015 to 2020 in the ewe hoggets. Gross margin (GM) was calculated for each genotype. Differences among genotypes for subjectively assessed wool quality traits were non-significant. Genotypes with a greater proportion of C had higher fleece weight, whereas those with a greater proportion of DM had lower fibre diameter. Pure C had the lowest post-shearing live weight whereas ½DM_½C had the highest. Pure C had the lowest GM for the scenarios investigated (low and high wool price, adjustment for greater feed intake of heavier hoggets). Rotational crossbreeding takes advantage of the complementarity between these two breeds, allowing a rapid enhancement of the C producers’ income from wool without compromising the meat-producing attributes of the breed. The advantage could be greater by implementing some simple selection strategies.

EFFECT OF THE INCLUSION OF FOLIAGE OF TROPICAL TREES ON DIGESTIBILITY, FERMENTATION, AND GAS PRODUCTION UNDER IN VITRO CONDITIONS

vie, 29 dic 2023 00:00:00 -0500

The objective of this study was to determine the effects of different levels of inclusion of tree species in combination with fiber (corn stover) on digestibility, fermentation and total gas production under in vitro conditions. Different levels of inclusion of tree foliage were evaluated: + fiber, F-100%; Brosimum alicastrum (Ba): Ba-10%+F-90%, Ba-20%+F-80%, and Ba-30%+F-70%; Guazuma ulmifolia (Gu): Gu-10%+F-90%, Gu-20%+F-80%, and Gu-30%+F-70%; Moringa oleifera (Mo): Mo-10%+F-90%, Mo-20%+F-80%, and Mo-30%+F-70; Gliricidia sepium (Gs): Gs-10%+F-90%, Gs-20%+F-80%, and Gs-30%+F-70%; Piscidia piscipula (Pp): Pp-10%+F-90%, Pp-20%+F-80%, and Pp-30%+F-70%; and Viguiera dentata (Vd): Vd-10%+F-90%, Vd-20%+F-80%, and Vd-30%+F-70%. The in vitro gas technique was used for 72 h. The experiment was conducted using in a randomized complete block design. Digestibility, total gas production and protozoan population were measured. The treatments Gu30%+70%F and Gu20%+80%F had higher crude protein content, with 12.8 and 9.79%, respectively. Regarding gas volume, the lowest value was recorded by Gu10%+90%F with 81.43%, followed by Pp20%+80%F with 110.01%. The lowest protozoal population was found in Ba30%+70%F and Gu20%+80%F, recording 3.12% and 3.36% log₁₀, respectively. Overall, the most suitable treatments as nutrient supply for ruminants were Gu30%+70%F, Gu20%+80%F, Ba30%+70%F, and Gs30%+70%F.

ENZYMES FROM Pleurotus ostreatus SPENT SUBSTRATE USED FOR FATTENING RABBITS: EFFECTS ON PRODUCTIVE PERFORMANCE, CARCASS TRAITS AND MEAT CHARACTERISTICS

vie, 29 dic 2023 00:00:00 -0500

Rabbit meat has a high nutritional value. The cost of rabbit feed is high, and thus it is important to find alternative feed sources with reduced costs. The objective was to evaluate the effects of enzymes obtained from the spent substrate of Pleurotus ostreatus on carcass traits and meat characteristics of fattening rabbits in order to recommend an alternative additive for rabbit feed. Spent substrate of P. ostreatus with different levels of enzymatic activity was used to feed growing rabbits. Ninety-sixty rabbits were selected and randomly distributed to four treatments: 0 (control without enzyme extract, C); 20000 (T20); 40000 (T40); and 60000 (T60) IU kg^-1 of laccase enzymes from the spent substrate of P. ostreatus. The experiment included six repetitions (four animals each) per treatment. Rabbits were fattened over 28 d and productive performance parameters were determined. Then, the animals were slaughtered, and carcass traits and meat characteristics were measured. The results indicated that total weight gain, total feed consumption, total daily weight gain, hot carcass weight, and dressing percentage decreased (p<0.05) as the amount of enzyme increased. However, the T40 treatment was similar to the control (p>0.05) for carcass traits, texture and pH, although L*, cooking loss and hardness recorded higher values (p<0.05). In conclusion, the spent substrate of P. ostreatus can be used to feed rabbits as some parameters of productive performance and carcass traits were similar to the control treatment.

FOTOPERIODO Y CONCENTRACIÓN PLASMÁTICA DE ESTRADIOL, PROGESTERONA Y TESTOSTERONA EN PAVO CRIOLLO (Meleagris gallopavo Linnaeus), EN LA REGION DE ÑUBLE, CHILE

vie, 29 dic 2023 00:00:00 -0500

El fotoperiodo es una de las señales ambientales de mayor impacto sobre la estimulación reproductiva de las aves, actuando directamente sobre el eje hipotálamo-pituitario-gonadal, estimulando la producción de testosterona en el macho y estrógeno y progesterona en la hembra. Este estudio aborda el papel del fotoperiodo sobre las concentraciones plasmáticas de testosterona, estradiol y progesterona, en pavos criollos (Meleagris gallopavo) del Hemisferio Sur. Los resultados pueden contribuir a aclarar las relaciones entre la cantidad de horas de luz del fotoperiodo estacional y las temporadas con mayor potencial reproductivo. Los estudios se efectuaron entre julio y diciembre en Chillán, Región de Ñuble, Chile. Se emplearon 24 pavas y 16 pavos en un fotoperiodo natural, negativo de días cortos hacia uno positivo de días largos. Se efectuaron recolecciones mensuales de sangre, utilizando la fracción de suero para determinar las concentraciones hormonales mediante la técnica de RIA, empleando kits comerciales de acuerdo a las recomendaciones del fabricante. Existen diferencias significativas (p < 0,05) en las concentraciones de estradiol, progesterona y testosterona a lo largo del ciclo reproductivo, con picos de estradiol, progesterona y testosterona coincidentes en los meses de septiembre y octubre, donde los aumentos de horas de luz diarias influyen significativamente (p < 0,05) en la concentración plasmática. En conclusión, la etapa de fines de invierno e inicios de primavera es el período de mayor interés reproductivo para la especie en los sistemas de crianza de traspatio en el hemisferio sur, favoreciendo el desarrollo de programas de conservación y reproducción.

LABRANZA MECANIZADA Y TRADICIONAL EN TERRAZAS DE LA PEQUEÑA AGRICULTURA ALTOANDINA EN PERÚ: COMPARACIÓN TÉCNICA Y ECONÓMICA

Catherine Alva, Noriyuki Baba — vie, 29 dic 2023 00:00:00 -0500

La delicada seguridad alimentaria, junto con la la crisis económica y ambiental que afectan a las poblaciones más vulnerables de la zona altoandina del Perú, han puesto de manifiesto la importancia de la pequeña agricultura. El objetivo de este estudio fue realizar un análisis comparativo entre la labranza mecanizada y la tradicional, a partir de variables técnicas y económicas. Para esto, se estimó el gasto energético de los operarios, el desempeño de los equipos de labranza, la profundidad y el diámetro medio ponderado (MWD) de suelo labrado, y los tiempos y costos de labranza por hectárea. En labranza tradicional se emplearon la barreta y la yunta, mientras que la labranza mecanizada incluyó el uso de tres modelos de motocultores. Las parcelas fueron terrazas tipo 3, tipo 3-2 y tipo 2. El diseño estadístico fue de bloques completamente al azar. Para el análisis estadístico se utilizó el ANOVA y la prueba DMS. Los resultados indican que los tipos de labranza y terrazas que demandan menores tiempos y costos de labranza son los motocultores, la yunta y las terrazas tipo 2, beneficiando a la economía y seguridad alimentaria rural. La yunta y los motocultores se pueden utilizar de forma combinada para roturar y mullir el suelo, respectivamente. Para mejorar la evaluación de las variables técnicas (gasto energético, profundidad y MWD de suelo labrado) se requiere de un periodo de estudio más largo y aumentar las repeticiones. Próximos estudios podrían evaluar otras tecnologías y labores culturales, incluyendo la participación de mujeres agricultoras.

FISIOLOGÍA Y TECNOLOGÍA DE POSTCOSECHA DE HORTALIZAS DE HOJA DE CUARTA GAMA: UNA REVISIÓN

Karin Albornoz , Amalia Hermosilla — vie, 29 dic 2023 00:00:00 -0500

Los productos de cuarta gama son frutas u hortalizas sometidas a procesos de pelado, troceado, rallado, entre otros. En su mayoría, son productos listos para consumir, ya que antes de envasarse son lavados y desinfectados. A lo largo de los años, el mercado de estos productos ha ido en crecimiento a nivel mundial. En Chile, su comercialización se encuentra limitada a un sector de nicho, debido a que los precios son elevados y en su mayoría son preferidos por personas de ingresos más altos. Dentro de estos productos se encuentran las hortalizas de hoja, que son altamente perecederas debido a sus elevadas tasas respiratorias y de transpiración, las cuales son exacerbadas por el procesamiento, por lo que es esencial minimizar la magnitud del daño mecánico y mantener temperaturas bajas durante el procesamiento y almacenamiento del producto. En este rubro, usualmente se utilizan filmes plásticos con permeabilidad selectiva a los gases que componen la atmósfera interna entre el envase y el vegetal, lo que es conocido como atmósferas modificadas. Estas benefician la calidad y duración del producto. En la industria de cuarta gama internacional, microorganismos patógenos que causan enfermedades en humanos han sido asociadas a distintos brotes, destacando Escherichia coli y Salmonella enterica. Por ello, es importante implementar buenas prácticas durante la elaboración del producto, como la utilización de métodos de sanitización para el lavado, buena higiene en el lugar de trabajo y mantención de temperaturas óptimas para asegurar la calidad microbiológica del producto final.

BIBLIOMETRIC ANALYSIS ON FORAGE CACTUS PRODUCTION, MANAGEMENT AND USE IN ANIMAL NUTRITION: DEVELOPMENT, CURRENT STATUS AND FUTURE RESEARCH

vie, 29 dic 2023 00:00:00 -0500

Forage cactus (FC) is a perennial crop primarily developed in semi-arid regions. In Brazil, it is one of the main feed sources for ruminants during the dry season. However, scientific research and publication on FC seem limited and recent. Bibliometric studies allow measuring publication patterns and understanding the evolution of scientific production. Thus, a bibliometric analysis was carried out to evaluate the scientific production on productive aspects, management, and use of FC in animal feed (1800-June 2022). The literature search was based on keywords, including “cactus, cacti, nopal, prickly pear, palma forrageira, cacto, Nopalea, Opuntia, forage, forragem, and forraje”. Data were analyzed using the Bibliometrix tool based on the R language through the Biblioshiny interface. A total of 514 publications were identified, with a predominance of research articles (92.6%). Scientific production includes authors from 40 countries, highlighting Brazil (1094 authors). The main sources were: Revista Brasileira de Zootecnia, Acta Horticulturae, Tropical Animal Health and Production, Revista Caatinga, Journal of the Professional Association for Cactus Development, and Revista Brasileira de Engenharia Agrícola e Ambiental. The 10 most frequent words were: Opuntia, Semiarid, Nopalea, Forage, Cactaceae, Opuntia fícus-indica, Cactus, Cactus pear, Intake, and Digestibility. Scientific production on FC is led by researchers from Brazil, notably from Northeastern Brazil. Publications on the economic evaluation, establishment and maintenance of promising species, soil conservation, micronutrient content and the use of FC as a supplementary source of water, are less frequent. These sub-areas suggest future lines of research that may be inter-institutional to increase collaboration networks between countries.

ESTADO ACTUAL DEL USO DE BIOINSUMOS MICROBIANOS EN COLOMBIA

Mónica Alejandra Rodríguez Aristizabal, María Camila Lugo Ramírez — vie, 29 dic 2023 00:00:00 -0500

El uso de bioinsumos en las prácticas agrícolas ha aumentado en los últimos años dada la crisis socioambiental que se vive en los países en vía de desarrollo, siendo una alternativa que surge en respuesta a la necesidad de cambiar los productos agroquímicos por productos sostenibles, y así evitar impactos negativos en el medio ambiente. Colombia, un país con vocación agrícola, no se queda atrás. En la actualidad, existen registrados ante el Instituto Colombiano Agropecuario (ICA) aproximadamente 375 productos de tipo bioinsumos, de los cuales 174 son formulaciones con base en microorganismos, que se aplican en diferentes sistemas productivos y que evidencian mecanismos de acción diversos. Esta revisión analizó el estado actual del uso de estos bioinsumos microbianos en el país. Se encontró que principalmente se usan bioplaguicidas, y que la mayoría de las formulaciones, independientemente del tipo de bioinsumo, usan bacterias como principales microorganismos, siendo los géneros más comunes Azotobacter sp., Bacillus sp., Burkholderia sp., Lactobacillus sp. y Pseudomonas sp. Además, se encontró que el principal uso de estos bioinsumos se ha orientado a los sistemas productivos como frutales y cereales. Esto coincide con la encuesta nacional agropecuaria realizada por el Departamento Administrativo Nacional de Estadísticas (DANE) en 2019, donde se informó que la mayor producción agrícola se concentra justamente en este tipo de cultivos. De acuerdo con esto, se puede concluir que el uso de bioinsumos como alternativa frente a las prácticas agrícolas convencionales ha venido aumentando en el país, convirtiéndose no sólo en una estrategia que promueve la sostenibilidad, sino también en una oportunidad para el desarrollo biotecnológico.

BEYOND RADIATA PINE BARK: TOWARDS SUSTAINABLE FOREST MANAGEMENT AND BIODIVERSITY CONSERVATION IN CHILE

Daniel Sandoval-Rivas, Reiner Romero-Garrido — vie, 29 dic 2023 00:00:00 -0500

Radiata pine is one of Chile's most widely planted tree species, and its bark is a by-product of the forestry industry. The use of radiata pine bark as an organic amendment to soil has been a frequent practice in Chilean agriculture. However, its impact on soil and biodiversity is still a matter of concern. This essay reviews the scientific literature on the use of radiata pine bark as a soil amendment, identifying the most common components used. These components are related to the transformation processes that allow the production of nutrients. The environmental consequences of the presence of radiata pine bark tannins on various organisms are also reviewed. Although there are components that contribute to an improvement in the soil such as resins as a source of phosphorus, or proteins as a source of nitrogen, in tannins there are components such as catechin that can affect the availability of nutrients. The work hopes to contribute to understanding of these components of radiata pine bark.

FIRST REPORT OF CACTUS WEEVIL (Cactophagus spinolae Gyllenhal) (COLEOPTERA: CURCULIONIDAE) FEEDING ON PITAHAYA (Selenicereus undatus (Haw.) D.R. Hunt (CACTACEAE) IN GUERRERO, MEXICO

vie, 29 dic 2023 00:00:00 -0500

EFECTO DE DIFERENTES DOSIS DE ÁCIDO GIBERÉLICO EN LA GERMINACIÓN DE PAPAYA (Carica papaya L.) VARIEDAD CRIOLLA

vie, 29 dic 2023 00:00:00 -0500

La papaya (Carica papaya L.) es un fruto tropical de gran interés socio- económico en Perú. Su principal forma de propagación es mediante semillas, las cuales presentan una gran desuniformidad en la germinación. El objetivo fue evaluar tres dosis de ácido giberélico (AG₃) y dos tiempos de imbibición en la germinación de semillas de papaya ´Criolla´. La investigación se realizó en el departamento de Morfofisiología Vegetal de la Universidad Nacional de Piura (5°10’33” S, 80°37’17” O, 30 m.s.n.m) de febrero a marzo de 2023. Se realizó un diseño completo al azar con cuatro tratamientos y cuatro repeticiones, con 20 semillas por repetición. Los datos se analizaron mediante un análisis de varianza (ANOVA) y la Prueba de Diferencia Mínima Significativa (LSD) de Fisher (p<0,05), utilizando el software estadístico Stagraphics versión 19. Los tratamientos fueron: T0 (testigo: agua), T1 (150 mg L^-1 AG₃), T2 (200 mg L^-1 AG₃), y T3 (250 mg L^-1 AG₃), durante 12 y 24 h de imbibición. Los parámetros evaluados fueron: porcentaje de germinación (PG), velocidad de germinación (VG), primer día de germinación (PDG) e índice de germinación (IG). Las semillas tratadas por 24 h de imbibición y a mayor concentración de AG₃, mejoraron el PG en 72,5%, la velocidad de germinación con 1,26 semillas germinadas por día, y el índice de germinación con 8,3, y redujeron el tiempo de inicio de germinación a 6 días. Se concluye que el tratamiento con 250 mg L^-1 de AG₃ durante 24 h de imbibición mejoró las variables evaluadas en las semillas de papaya ´Criolla´.

SEED VIABILITY, GERMINATION, AND SEEDLING GROWTH OF CAPSICUM CULTIVATED SPECIES

vie, 29 dic 2023 00:00:00 -0500

Seed viability of domesticated and cultivated Capsicum species: Capsicum annuum L., Capsicum baccatum L., Capsicum chinense Jacq., Capsicum frutescens L., and Capsicum pubescens Ruiz & Pav. was tested by the tetrazolium method. The seeds were soaked in three tetrazolium salt solutions of 1, 0.5 and 0.2%, and temperature conditions of 30 - 35 °C for 3 h. The percentage of seeds stained in relation to the total number of seeds was evaluated. To estimate germination, the seeds were subjected to chemical treatments with gibberellic acid (GA₃) at doses of 0, 100, 200, 300, and 400 mg L^-1 at room temperature for 24 h. The germination rate was estimated, while plant height was evaluated at 10, 20 and, 30 days after sowing (DAS). Capsicum seed viability fluctuated between 52.44% and 97.11%. The highest percentage of viability was obtained with the 1% dose of tetrazolium (81.63%), while the 0.2% dose resulted in the lowest average value (63.7%). In addition, C. annuum, C. baccatum and C. chinense showed high staining patterns, while most of the observed patterns in C. frutescens corresponded to non-viable seeds. After GA₃ application, average seed germination was 100% in C. chinense; 75.6% in C. baccatum; 73.32% in C. annuum; and 61.5% in C. frutescens. However, the application of GA₃ did not cause an additional effect on the germination of Capsicum seeds. The highest plant height at 30 DAS was observed in accessions of C. annuum (9.08 cm), while C. chinense presented the lowest value (4.49 cm).