Ciencia E Investigacion Agraria最新文献

{"title":"Aging gene pathway of microRNAs 156/157 and 172 is altered in juvenile and adult plants from in vitro propagated Prunus sp.","authors":"Adriana Bastías, R. Almada, P. Rojas, J. M. Donoso, R. P. Hinrichsen, D. Sagredo","doi":"10.4067/S0718-16202016000300009","DOIUrl":"https://doi.org/10.4067/S0718-16202016000300009","url":null,"abstract":"In vitro culture is a very popular technique to mass propagate valuable plant genotypes, including Prunus sp. cultivars. Plants that undergo tissue culture processes often change their morphology and behavior due to the “rejuvenation” caused by the plant growth regulators included in the medium. To evaluate the effects of rejuvenation by tissue culture in Prunus sp., the expression patterns of the aging gene pathway described in plant models, which include the highly conserved microRNA (miRNA or miR) 156/157 and 172 families and several of their respective target genes, were analyzed in distinct Prunus sp. genotypes at different phases of maturity, including true seedling and tissue culture micropropagated plants. In genotypes from true seedling plants, the expression of miR156 and miR157 was higher in the leaves of juvenile plants (one year old) than in those of adult plants (six year old). The opposite pattern was observed with miRNA172 expression. Our results suggest that the aging gene pathway is relatively conserved in Prunus and likely plays a key role in vegetative phase change. However, Prunus sp. plants that were rejuvenated and propagated by in vitro methods showed more erratic behavior for miR156 and miR157 and their target genes, suggesting that tissue culture alters the normal control of the aging pathway. El cultivo in vitro es una tecnica muy popular para propagar en masa genotipos de plantas valiosas, incluyendo cultivares de Prunus sp. Las plantas que se someten a procesos de cultivo de tejidos a menudo cambian su morfologia y comportamiento debido a la “rejuvenilizacion” causada por los reguladores de crecimiento de planta incluidos en el medio. Para evaluar el efecto de la rejuvenilizacion por cultivo de tejido en Prunus sp, los patrones de expresion de la via genica del envejecimiento descrita en plantas modelos, la cual incluye a las familias altamente conservadas de microRNAs (miR) 156/157 y miR172 y varios de sus genes blancos respectivos, fueron analizados en diferentes genotipos de Prunus sp. En fases de madurez distintas, incluyendo tanto plantas provenientes de semilla verdadera como micropropagadas mediante cultivo de tejidos. En los genotipos de plantas que provienen de semilla verdadera, la expresion de microR156 and miR157 fue mas alta en hojas de plantas juveniles que en plantas adultas. El patron opuesto fue observado con el patron de expresion de miR172. Nuestros resultados sugieren que la via genica del envejecimiento es conservada en Prunus y probablemente juega una funcion en el cambio de fase vegetativo. Sin embargo, plantas de Prunus sp. que fueron rejuvenecidas y propagadas por metodos in vitro mostraron un comportamiento mas erratico para los mi156 y miR157 y sus genes blancos, sugiriendo que el cultivo de tejidos altera el control normal de la via del envejecimiento.","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"133 1","pages":"429-441"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81356832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of a spray-dried fat enriched with EPA and DHA on the fatty acid composition of sow milk","authors":"M. Grez, M. Gandarillas, F. González, Einar Vargas-Bello-Pérez","doi":"10.7764/RCIA.V43I3.1724","DOIUrl":"https://doi.org/10.7764/RCIA.V43I3.1724","url":null,"abstract":"Supplementation with eicosapentaenoic and docosahexaenoic acids (EPA and DHA) through the addition of fish oils to mammal diets during lactation benefits milk production, litter growth and the litter immune system, but there is little evidence supporting the use of oils that have been dried using a spray-drying method designed to cool and crystalize fat particles. The objective of this study was to evaluate the effect of a spray-dried dietary fat enriched with EPA and DHA on the fatty acid composition of sow milk. Fifteen pregnant sows were assigned to three dietary treatments from day 100 of gestation until weaning (day 28). Control sows (CONT) were fed an unsupplemented basal diet, and supplemented sows were fed the basal diet plus 20 g (FOPF20) or 40 g (FOPF40) of a spray-dried powdered fat enriched with EPA and DHA. Milk and colostrum compositions and milk yield were similar among diets, and the main milk fatty acids (FA) were C14:0, C16:0, C18:0, C18:1 n-9 and C18:2 n-6. Supplementation with EPA and DHA (FOPF20 and FOPF40) decreased the saturated FA contents and increased the amount of polyunsaturated FA. In summary, the results indicated that supplementing sow diets with EPA and DHA could decrease the saturated fatty acid content and increase the polyunsaturated fatty acid content of milk. El objetivo de este estudio fue evaluar el efecto de fuentes dietarias enriquecidas con EPA y DHA (Acidos eicosapentaenoico y docosahexaenoico) sobre el perfil de acidos grasos de leche de cerda. Quince cerdas prenadas fueron repartidas en tres tratamientos desde el dia 100 de gestacion hasta el destete de lechones (dia 28). Las cerdas del grupo control (CONT) fueron alimentadas con una dieta basal sin suplemento de EPA y DHA. Las cerdas alimentadas con dietas suplementadas recibieron una dieta basal con 20 g (FOPF20) o 40 g (FOPF40) de grasa en polvo enriquecida con EPA y DHA. La composicion de leche y calostro y la produccion de leche de las cerdas fueron similares entre tratamientos. Los principales acidos grasos en leche fueron: C14:0, C16:0, C18:0, C18:1 n-9 y C18:2 n-6. La suplementacion con EPA y DHA (FOPF20 y FOPF40) disminuyo el contenido de acidos grasos saturados e incremento poliinsaturados. En resumen, los resultados indicaron que la suplementacion de dietas de cerdas con EPA y DHA puede disminuir el contenido de acidos grasos saturados e incrementar contenido de acidos grasos poliinsaturados.","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"90 1","pages":"347-355"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81552081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Systematic transitions in land use and land cover in a pre-Andean subwatershed with high human intervention in the Araucania Region, Chile","authors":"P. S. Briones, A. Sepúlveda-Varas","doi":"10.4067/S0718-16202016000300006","DOIUrl":"https://doi.org/10.4067/S0718-16202016000300006","url":null,"abstract":"Historical studies of land use changes help us to understand the current configuration of the landscape and identify the environmental and social impacts that are associated with these transformations. Several authors describe the transitions as a process of change that transforms the landscape system; for systematic transitions, these transitions are driven by stable and gradual processes. The objective of this study is to determine the trajectory and magnitude of land use and land cover (LULC) change for the 1994-2007 period in a pre-Andean sub-watershed with intensive human use in the central-southern zone of Chile and to analyze the most significant systematic transitions between land cover types. The results confirmed the reduction in the areas of agriculture and livestock and the increase of exotic plantations use on surfaces intended for agricultural use. The significant transitions were the conversion at a rate gain of 384 ha/year of “Farmlands” to “Exotic plantations”, the abandonment at a loss rate of 119 ha/year of “Perennial grasslands” to “Native vegetation”, the degradation at a loss rate of 93 ha/year of “Native vegetation” to “Perennial grassland”, and the revegetation at a rate gain of 60 ha/year of “Exotic plantations” to “Native vegetation”. The new patterns and trends in the use and intensity of land use reaffirmed the need for studies on the updated status of natural resources, particularly soil resources. This work, we believe, is a technical tool to support the sustainable management of a territory and the decision-making processes on land use. Estudios de los cambios en el uso de la tierra permiten comprender la configuracion actual del paisaje e identificar los impactos ambientales y sociales que se asocian a estas transformaciones. Diversos autores describen “transiciones” como un proceso de cambio que transforma el paisaje, donde las “transiciones sistematicas” son impulsadas por procesos estables y graduales. El objetivo de este estudio es determinar la trayectoria y magnitud del cambio de cobertura y uso de la tierra para el periodo 1994-2007 en sub-cuenca pre-andina de uso intensivo en el centro-sur de Chile y analizar las transiciones sistematicas mas significativas entre tipos de cobertura. Los resultados obtenidos confirman la reduccion de areas destinadas a agricultura-ganaderia y el aumento de areas de uso forestal: conversion, a una tasa de 384 ha ano-1, de “Cultivos y pastizales naturales” a “Plantaciones forestales”; abandono, a una tasa de perdida de 119 ha ano-1, de “Praderas perennes” a “Bosque nativo y matorrales”; degradacion, a una tasa de perdida de 93 ha/ano, de “Bosque nativo y matorrales” a “Pastizal perenne”; y revegetacion, a una tasa de ganancia de 60 ha ano-1, de “Plantaciones forestales” a “Bosques y matorrales nativos”. Asi, debido a los nuevos patrones y tendencias en el uso de la tierra se reafirma la necesidad de contar con estudios sobre el estado actualizado de los recursos naturales, en ","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"7 1","pages":"396-407"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79495287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of foliar boron spraying on the fruit features of Brigitta and Legacy highbush blueberry (Vaccinium corymbosum) cultivars","authors":"C. Meriño-Gergichevich, E. Pacheco, M. Reyes-Díaz","doi":"10.4067/S0718-16202016000300011","DOIUrl":"https://doi.org/10.4067/S0718-16202016000300011","url":null,"abstract":"Boron (B) is associated with reproductive and antioxidant metabolism in plants, and in southern Chile, the deficiency of this micronutrient is ameliorated through foliar applications that are a part of agricultural management, thus ensuring the productivity of crops including highbush blueberry ( Vaccinium corymbosum L.). However, the appropriate B dosage for this species is unknown, so the aim of this study was to evaluate foliar B application on fruit quality in highbush blueberry in southern Chile. During the 2014-2015 season, Brigitta and Legacy cultivars were sprayed with B at rates of 0 (control), 200, 400 and 800 mg L-1 three times (10% bloom, full bloom, and fruit set), and fruit set (%), firmness (g mm-2), soluble solids (°Brix), weight (g) and size (mm) of the fruits were determined. In addition, antioxidant activity was measured by ORAC (oxygen radical absorbance capacity) and DPPH (2,2-diphenyl-1-picrylhydrazyl). The results showed that a low rate of B (200 mg L-1) increased the fruit set and soluble solids in Brigitta, whereas Legacy required higher B concentrations (400 and 800 mg L-1). In both cultivars, firmness, fresh fruit weight, dry matter (%) and antioxidant activity increased under the 200 and 400 mg B L-1 treatments, whereas this last parameter was reduced under a high B concentration. A low B rate showed to be more effective at improving fruit quality in Brigitta, while Legacy required higher B application rates. Future research should be performed over several seasons and different cultivars to confirm these results. El boro (B) esta asociado al metabolismo reproductivo y antioxidante en plantas. En el sur de Chile, su deficiencia es resuelta con aplicaciones foliares de este micronutriente como parte del manejo agronomico, asegurando asi la productividad en cultivos como arandano alto ( Vaccinium corymbosum L.). Sin embargo, la informacion sobre dosis adecuadas para esta especie es escasa. Se evaluo la aplicacion foliar de B sobre parametros de calidad en fruta de arandano alto del sur de Chile. En la temporada 2014-2015, plantas de cultivares Brigitta y Legacy, fueron asperjadas con B en dosis de 0 (control), 200, 400 y 800 mg L-1 en tres momentos durante la temporada (10% floracion, plena flor y fruto cuajado), determinandose: frutos cuajados (%), firmeza (g mm-2), solidos solubles (oBrix), peso (g) y calibre (mm), ademas de la actividad antioxidante mediante ORAC (oxygen radical absorbance capacity) y DPPH (2,2-diphenyl-1-picrylhydrazyl). Una baja dosis de B (200 mg L-1) incremento la cuaja y solidos solubles en Brigitta, mientras que Legacy requirio mayores concentraciones de B (400 y 800 mg L-1). En ambos cultivares aumento la firmeza, peso fresco y seco de la fruta, asi como la actividad antioxidante al ser tratada con 200 y 400 mg B L-1, mientras en alta concentracion disminuyo este ultimo parametro. Una baja dosis de B resulto ser efectiva mejorando la calidad de la fruta en el cultivar Brigitta, mientras que Leg","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"549 1","pages":"452-463"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85663421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enfoque estadístico para evaluar la heterogeneidad de paltas Hass, sometidas a diferentes estreses abióticos en postcosecha","authors":"C. Fuentealba, Romina Pedreschi, I. Hernández, J. Saavedra","doi":"10.4067/S0718-16202016000300002","DOIUrl":"https://doi.org/10.4067/S0718-16202016000300002","url":null,"abstract":"","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"313 1","pages":"356-365"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77511959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial patterns over a 24-year period show an increase in native vegetation cover and decreased fragmentation in Andean temperate landscapes, Chile","authors":"Robert Petitpas, J. Ibarra, M. Miranda, C. Bonacic","doi":"10.4067/S0718-16202016000300004","DOIUrl":"https://doi.org/10.4067/S0718-16202016000300004","url":null,"abstract":"Changes in landscape pattern were studied in a temperate landscape of the La Araucania Region, Chile. Using aerial photographs from 1983 and 2007, we created land use/land cover maps. We then quantified the changes in composition and configuration by using landscape metrics and an adjacency matrix. By 2007, the dominant land cover had changed from agriculture to native vegetation. Residential areas showed the largest relative increase (670%) and had significant adjacency with native vegetation. The native vegetation increased by 375 ha, but the number of patches decreased by 45% and the mean patch area increased by 124%, which indicated that fragmentation decreased. The growth of tourism and the preference for “natural” spaces by new residents are suggested as the main drivers of this native vegetation recovery. Understanding the process of forest recovery may be helpful for reversing the general trend of forest loss in temperate forests of South America. This research is a first approach in exploring specific cases of native vegetation recovery and decreases in fragmentation in this Global Biodiversity Hotspot. Los cambios en los patrones espaciales fueron estudiados en un paisaje templado de la region de La Araucania, Chile. Se hicieron mapas de cobertura y uso del suelo a partir de fotografias aereas de los anos 1983 y 2007. Los cambios en composicion y configuracion del paisaje se obtuvieron a partir de metricas y una matriz de adyacencia. Para el ano 2007, la cobertura dominante cambio desde agricultura a vegetacion nativa. Las areas residenciales presentaron el mayor aumento porcentual (670%) y una importante relacion de adyacencia con la vegetacion nativa. La vegetacion nativa aumento en 375 ha, pero el numero de parches de esta disminuyo en un 45% y el area media de los parches aumento un 124%, lo que indica una disminucion en la fragmentacion. El incremento del turismo y la preferencia de espacios naturales entre los nuevos residentes del area seria la principal fuerza de cambio detras de la recuperacion de la vegetacion nativa. Considerando la perdida actual de la vegetacion nativa en el area, se hace importante que futuros estudios consideren casos especificos de recuperacion de esta, para asi entender los factores asociados a este proceso. Esta investigacion es una primera aproximacion para entender la recuperacion y disminucion de la fragmentacion de la vegetacion nativa de los ecosistemas templados de America del Sur.","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"10 5 1","pages":"384-395"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4067/S0718-16202016000300004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72534321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A statistical approach for assessing the heterogeneity of Hass avocados subjected to different postharvest abiotic stresses","authors":"C. Fuentealba, R. Pedreschi, Ignacia Hernández, J. Saavedra","doi":"10.7764/RCIA.V43I3.1725","DOIUrl":"https://doi.org/10.7764/RCIA.V43I3.1725","url":null,"abstract":"Hass avocado ( Persea americana Mill.) is marketed worldwide. Due to its complex physiology, a wide variability in postharvest ripening can be observed, i.e., heterogeneity in the number of days to reach edible ripeness. There is a need for a simple and objective method for evaluating the efficacy of postharvest treatments in the reduction of this postharvest ripening heterogeneity given the high demand of import countries for consistent quality and product homogeneity. Therefore, the aim of this study was to compare the appropriateness of different statistical methods used to evaluate this ripening heterogeneity. Bartlett’s, Cochran’s, Levene’s homogeneity of variance tests were applied to different treatments. In addition, a multiple comparisons test of squared residuals (parametric and non-parametric) was applied. The classical statistical approaches (Bartlett’s, Cochran’s and Levene’s tests) showed similar results as the multiple comparisons test of squared residuals only when one treatment and large sample sizes (n=100) were evaluated. All statistical methods were able to detect significant differences in ripening heterogeneity from growers and storage conditions. The multiple comparisons test of squared residuals was the most suitable method for multifactorial experiments and small sample sizes (n=30) compared to the classical approaches, which increased the probability of obtaining false positives or a type I error. La palta Hass ( Persea americana Mill.) es mundialmente comercializada y los paises importadores demandan productos homogeneos y de calidad consistente. Sin embargo, debido a la compleja fisiologia del fruto se observa una amplia variabilidad durante su maduracion postcosecha, es decir, heterogeneidad en los dias para alcanzar la madurez comercial. Por tal motivo, es necesario evaluar la eficacia de tratamientos postcosecha en la reduccion de la heterogeneidad en la maduracion a traves de un metodo objetivo y simple. El objetivo de este estudio fue comparar diferentes metodos estadisticos para la evaluacion de la heterogeneidad en la maduracion. A los diferentes tratamientos se aplicaron pruebas de homogeneidad de varianza como Bartlett, Cochran, Levene. Ademas, se realizo una comparacion multiple a residuales cuadraticos (parametricos y no parametricos). Las pruebas estadisticas clasicas (Bartlett, Cochran y Levene) mostraron resultados similares a la comparacion multiple de residuos cuadraticos solo cuando el tamano de muestra es grande (n=100) y se realiza solo un tratamiento. Todos los metodos estadisticos fueron capaces de detectar diferencias significativas en la heterogeneidad en la maduracion entre productores y diferentes condiciones de almacenamiento. La comparacion multiple de residuos cuadraticos fue el metodo mas adecuado para experimentos multifactoriales y de tamanos de muestras mas pequenos (n=30) en comparacion con las pruebas clasicas, donde estas ultimas conducen a un aumento en la probabilidad de obtener fal","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"26 1","pages":"356-365"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75888214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of flower preservative solutions during postharvest of Hydrangea macrophylla cv. Bela","authors":"D. Aros, Cristiana Silva, C. Char, L. Prat, V. Escalona","doi":"10.4067/S0718-16202016000300008","DOIUrl":"https://doi.org/10.4067/S0718-16202016000300008","url":null,"abstract":"Hydrangea macrophylla (hydrangea) is widely used as an ornamental plant and cut flower due to its inflorescence, which is composed of colored bracts. As cut flowers, hydrangeas show a postharvest life of up to 1 month at 2 °C, but little is known about their postharvest life during air shipment. This study was aimed at evaluating the effect of Triton X-100 (surfactant) and ClO2 (biocide) during an air shipment simulation of hydrangea harvested at two floral stages of development: fresh and antique. Vase life, fresh weight loss (FWL) and solution uptake were evaluated after an air shipment simulation. Furthermore, bacterial counts and microscopic observation of the bracts were performed in order to understand the water relations of hydrangea during vase life. The longest vase life was observed in antique hydrangeas, and the control (deionized water) was the best treatment, reaching up to 32.7 days in this floral stage. FWL was faster when using Triton X-100 (3.83 days to lose 20% of FW) compared to deionized water (8.75 days). However, this flower preservative was efficient at promoting solution uptake (31.96 mL). Bacterial plugging did not appear to occur considering that the high presence of microorganisms counted did not affect solution uptake or vase life. The presence of stomata on the bracts seems to be crucial for the dehydration of the inflorescence, a problem that was not solved by the higher water uptake promoted by Triton X-100. Thus, deionized water was the best treatment, and the effect of flower preservatives in order to extend vase life of hydrangea cut flowers was insignificant. Hydrangea macrophylla (hortensia) es ampliamente utilizada como planta ornamental y flor de corte debido a su inflorescencia compuesta por bracteas coloreadas. Como flor de corte, las hortensias presentan una vida en postcosecha de hasta un mes a 2°C pero poco se conoce sobre su postcosecha durante un envio aereo. Este estudio tuvo como objetivo evaluar el efecto de Triton X-100 (surfactante) y ClO2 (biocida) durante una simulacion de envio aereo de hortensias cosechadas en dos estados de desarrollo floral: ‘fresh’ y ‘antique’. Durante esta simulacion aerea se evaluo vida en florero, perdida de peso fresco y captura de solucion. Ademas, se realizo un conteo de bacterias y observaciones microscopicas de las bracteas para entender las relaciones hidricas durante la vida en florero. La vida en florero mas prolongada se observo en hortensias ‘antique’ y el control (agua deionizada) fue el mejor tratamiento alcanzando hasta 32,7 dias en este estado floral. La perdida de peso fresco fue mas rapida cuando se utilizo Triton X-100 (3,83 dias para perder 20% of peso fresco) en comparacion con el agua deionizada (8,75 dias). Sin embargo, este preservante floral fue eficiente en promover la captura de solucion (31,96 mL). El taponamiento por bacteria no fue sugerido para esta especie considerando que la alta presencia de microorganismos contabilizados no afecto la capt","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"1 1","pages":"418-428"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88169679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling Peruvian organic consumers demand for organics: A latent class approach","authors":"A. Higuchi, J. Dávalos","doi":"10.4067/S0718-16202016000300007","DOIUrl":"https://doi.org/10.4067/S0718-16202016000300007","url":null,"abstract":"This paper seeks to identify the consumer segments that constitute the market for organic products in Metropolitan Lima, Peru. The employed classification methodology, Latent Class Analysis, is implemented within a structural framework that is capable of identifying key relations such as the link between educational attainment and organic product consumption. This study builds on primary data gathered at the study site involving interviews with 547 organic consumers at a limited number of bio-fairs and bio-shops. Our results identify two segments: core and middle-level consumers. Although both segments exhibit similar concerns towards the environment, healthiness and tastiness, the core level exhibits higher preferences for the remaining attributes, controlling for demographical variables. Finally, this research provides evidence that educational attainment increases the likelihood of being a middle-level organic consumer. La presente investigacion tiene por objetivo identificar los segmentos de mercado de consumidores de productos organicos en Lima Metropolitana (Peru). Ademas, se implementa como metodologia de clasificacion el analisis de clases latentes, en conjunto con un marco estructural capaz de identificar relaciones clave, como por ejemplo el vinculo entre el nivel de educacion y el consumo de productos organicos. La investigacion se basa en informacion primaria recabada en el lugar de estudio, comprendiendo entrevistas con 547 consumidores de productos organicos en un numero limitado de tiendas y ferias organicas. Los resultados muestran dos segmentos de consumidores, el segmento de nivel medio y el segmento de nivel central. A pesar de que ambos segmentos identificados poseen actitudes similares con respecto al medio ambiente, la salud y el sabor, el segmento de nivel central exhibe niveles de preferencia mayores en los atributos restantes, controlando los efectos de las variables demograficas. Finalmente, la investigacion brinda evidencia de que dado un incremento en el nivel de educacion, la probabilidad de ser clasificado como un consumidor de productos organicos de nivel medio aumenta.","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"66 1","pages":"408-417"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75970881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of resistance expression in genotypes of Solanum Section Lycopersicon against Tuta absoluta (Lepidoptera: Gelechiidae)","authors":"Nancy Vitta, P. Estay, R. Chorbadjian","doi":"10.4067/S0718-16202016000300003","DOIUrl":"https://doi.org/10.4067/S0718-16202016000300003","url":null,"abstract":"Two studies were conducted with the aim of characterizing the antixenosis and antibiosis resistance expression of genotypes in the Solanum section Lycopersicon against Tuta absoluta (Meyrick). The species used were S. lycopersicum (Fiorentino, Naomi and Belle), S. habrochaites (RCAT030597, PI126446), S. chilense (INIABB79), S. peruvianum (RCAT031296, RCAT039874 and RCAT030403) and S. pimpinellifolium (PI390739). For the antixenosis bioassay, a leaf was removed from plants of each genotype and placed in a cup with a floral foam soaked in water. The cups were stored in cages covered with anti-aphid mesh. The number of eggs per plant was determined seven days after releasing the adults. For the antibiosis bioassay, one leaf per genotype and replication was placed in a plastic cup with floral foam soaked in water, and first-stage tomato leaf miner larvae were placed individually on the leaves. Larval survival, total average male and female pupal weight and consumed foliar area were assessed for each genotype. It was determined that most wild species showed resistance to Tuta absoluta by antixenosis and antibiosis mechanisms. The genotype S. habrochaites (RCAT030597) presented more resistance by antibiosis based on larval survival. Nonetheless, the resistance-level characterization depended on the insect response that was considered because S. chilense was less preferred for oviposition; however, in this genotype, the larval survival in the no-choice assays was among the highest observed. Thus, this study provides comprehensive information on the resistance level of several Solanum genotypes that could be used in further efforts to understand the complex mechanisms underlying Solanum resistance to the tomato leaf miner. Se condujeron dos estudios para caracterizar los mecanismos de resistencia por antixenosis y antibiosis de genotipos de Solanum seccion Lycopersicon a Tuta absoluta (Meyrick). Las especies utilizadas fueron Solanum lycopersicum (Fiorentino, Naomi y Belle), S. habrochaites (RCAT030597, PI126446), S. chilense (INIABB79), S. peruvianum (RCAT031296, RCAT039874, RCAT030403) y S. pimpinellifolium (PI390739). Para la evaluacion de antixenosis, se retiro una hoja de cada planta y se coloco en un recipiente con espuma floral embebida en agua. Los recipientes se introdujeron en jaulas cubiertas de malla anti-afidos. Se determino el numero de huevos por planta a los siete dias despues de la liberacion de los adultos. Similarmente, pero en forma independiente, cada hoja se inoculo con una larva de primer estado, evaluandose su sobrevivencia, peso final de pupas hembras y machos y el area foliar consumida. Se determino que la mayoria de los genotipos silvestres expresaron mecanismos de resistencia a Tuta absoluta por antixenosis y/o antibiosis. El genotipo S. habrochaites (RCAT030597) presento mayor resistencia por antibiosis basado en la sobrevivencia de las larvas y dano foliar. No obstante, la caracterizacion del nivel de resistencia dependio de","PeriodicalId":50695,"journal":{"name":"Ciencia E Investigacion Agraria","volume":"59 1","pages":"366-373"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87146327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}