Volumen 115 | Número 01

Uso de atmósfera controlada y 1-MCP en kiwis Hayward producidos en Argentina: efectos sobre la maduración

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Controlled atmosphere storage and 1-MCP of Hayward kiwifruits grown in Argentina: effects on ripening Revista de la Facultad de Agronomía; vol. 115, no. 1 Se estudió el efecto del uso de la atmósfera controlada (AC), 1-metilciclopropeno (1-MCP) y su combinación, sobre la maduración del kiwi ‘Hayward’. Frutos cosechados con 16,6% de materia seca y 9% de sólidos solubles totales (SST) fueron enfriados y tratados con 1000 ppb de 1-MCP (SmartFresh) durante 24h o permanecieron sin tratar con 1-MCP (controles). Posteriormente, frutas controles y tratadas con 1-MCP fueron almacenadas en cámara de frío convencional (FC, 0 °C y 90% HR) o en cámara de atmósfera controlada (AC, 2% O2 y 5% CO2, 0 °C; 90% HR) durante 5 meses (5m). Al finalizar, muestras de todas las combinaciones de tratamiento permanecieron durante un mes adicional en FC (5m + 1m). A la cosecha, a los 5m y 5m + 1m y después de la poscámara (7 días a 20 °C) se midieron el índice de color (en base a L*, a*, b* de CIE) y la firmeza de la pulpa (N), el SST (%) y la acidez titulable (AT, %). También se evaluó la dureza de columela al final de la poscámara, mediante análisis sensorial. Los tratamientos afectaron fundamentalmente la firmeza de la pulpa y de la columela. Los frutos almacenados en AC resultaron significativamente más firmes que los almacenados en FC, tanto a los 5m como a los 5m + 1m, evidenciando el efecto residual de dicha tecnología. Igual resultado se encontró para dureza de columela. El uso de 1-MCP en combinación con la AC también mostró un efecto sinérgico sobre la firmeza a los 5m + 1m, permitiendo prolongar el período de almacenamiento de los frutos.; The effect of the use of controlled atmosphere (CA), 1-methylcyclopropene (1-MCP) and their combination on the ripening of ‘Hayward’ kiwifruits was studied. Fruits harvested with 16.6% dry matter and 9% of total soluble solids (TSS) were cooled and treated with 1000 ppb of 1-MCP (SmartFresh) for 24 hours or remained untreated (controls). Untreated and 1-MCP-treated fruits were kept at cold storage (CS, 0 °C and 90% RH) or at controlled atmosphere storage (CA, 2% O2 and 5% CO2, 0 °C and 90% RH) for 5 months (5m). Subsequently, samples from all treatment combinations remained for an additional month at CS (5m + 1m). At harvest, 5m and 5m+1m and shelf-life (7 days at 20 °C), color index (based on L*, a*, b* of CIE) and flesh firmness (N), TSS (%) and titratable acidity (TA, %) were measured. Hard core was also evaluated by sensory analysis at shelf-life. Treatments mainly affected the flesh firmness and hard core. Fruits stored in CA were significantly firmer than those stored in CS, both at 5m and 5m+1m, showing the residual effect of this technology. The same result was found for hard core. The use of 1-MCP in combination with CA also showed a synergistic effect on flesh firmness at 5m + 1m, prolonging the storage period of the fruits.

Evaluación xilológica de familias mejoradas de sauces con destino industrial maderero

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Xylem evaluation of improved willow families for timber industrial use Revista de la Facultad de Agronomía; vol. 115, no. 1 El objetivo del trabajo fue la evaluación a edad temprana de la anatomía y densidad de la madera y su relación con el crecimiento en diámetro en 18 familias de sauces, con vistas a seleccionar clones aptos para la producción de madera para usos sólidos y papel. Se cruzaron progenitores de ocho especies de sauces (Salix alba, S. amygdaloides, S. babylonica, S. matsudanaS. humboldtiana, S. jessoensis, S. viminalis y S. nigra), obteniéndose individuos correspondientes a 18 familias. Se seleccionaron 365 individuos dentro de las familias sobre los cuales se evaluaron las propiedades de la madera a los 3 años de edad. La familia resultó una fuente significativa de variación tanto para el crecimiento como para las propiedades de la madera. El crecimiento en diámetro presentó correlación positiva con la densidad de la madera (r= 0,47) y con el diámetro de vasos (r= 0,73) y negativa con la frecuencia de vasos (r= -0,59). La longitud de fibras no se correlacionó significativamente con ninguna variable medida. Por lo tanto es posible, hallar combinaciones de buen diámetro, con alta densidad y altos valores de longitud de fibras. Se destacaron los cruzamientos donde intervienen como progenitor femenino S. amygdaloides y S. matsudana, ya que demostraron las mejores combinaciones de propiedades para diferentes destinos industriales como son: buen crecimiento en diámetro (mayores a 5cm), con altas densidades de la madera (mayores a 0,400 g/cm³) y mayores longitudes de fibras (superiores a 700 μm). Se aconseja la propagación de ciertas familias promisorias para aserrado y para papel.; The objective of this study was to evaluate the anatomy and wood density at early age and its relation to the growth in diameter. 18 willow´s families were evaluated to select clones suitable for the production of solid wood and paper applications. Parents of eight species of willows were crossed (Salix alba, S. amygdaloides, S. babylonica, S. matsudanaS. humboldtiana, S. jessoensis, S. viminalis y S. nigra) and individuals for 18 families were taken. 365 genotypes were selected and their wood properties at the age of 3 years were evaluated. The family was a significant source of variation for both growth and for the properties of wood. Diameter growth was positively correlated with wood density (r= 0.47) and vessel diameter (r= 0.73) but it was negatively correlated with the frequency of vessels (r= -0.59). The fiber length was not significantly correlated with any measured variable. Therefore, it is possible to select clones with great diameter, high density and high fiber length. Crosses which involved S. amygdaloides and S. matsudana as female parent stood out, as they showed the best combination of properties for different industrial destinations such as: good growth in diameter (greater than 5 cm), with high wood densities (greater to 0,400 g/cm³) and high fiber lengths (over 700 μm). Certain promising families are recommended for sawing and paper industry.

Biofumigación in vitro con Brassica juncea y Sinapis alba: Inhibición de la germinación y del crecimiento de plántulas de malezas

Fri, 01 Jan 2016 00:00:00 GMT

Articulo In vitro biofumigation with Brassica juncea and Sinapis alba. Inhibition of germination and growth seedlings of weeds Revista de la Facultad de Agronomía; vol. 115, no. 1 La biofumigación consiste en la incorporación en el suelo de residuos orgánicos, que generan durante su descomposición sustancias con actividad biocida. El objetivo de este trabajo fue determinar in vitro el efecto herbicida de la biofumigación con Brassica juncea L. Czerniak (mostaza parda) y Sinapis alba L. (mostaza blanca), en el estadio de fin de fructificación, sobre la germinación y el crecimiento de plántulas de tres especies arvenses: Anoda cristata (L.) Schltdl. (malva cimarrona), Picris echiodes L. y Portulaca oleracea L. (verdolaga). Plantas de mostaza parda y blanca se trituraron y colocaron por separado en recipientes de plástico, en dosis de 10 y 40 g; sobre ese material se apoyó una caja de Petri con papel absorbente humedecido, que contenía 50 semillas de una especie arvense. Se incubó a 24 ± 2ºC, con fotoperíodo de 12h/12h luz-oscuridad. A los 8 días se extrajo el material biofumigante y se prosiguió con la incubación hasta el día 21. Brassica juncea, en las dos dosis evaluadas, inhibió significativamente la germinación de las malezas. Sinapis alba solo inhibió la germinación de A. cristata y P. echiodes en la dosis de 40 g; sin embargo, en todos los tratamientos ralentizó significativamente el crecimiento de las plántulas de las tres especies arvenses. Los resultados obtenidos in vitro sugieren que B. juncea tendría mayor potencial que S. alba para controlar biológicamente las malezas A. cristata, P. echiodes y P. oleracea.; Biofumigation consists of the incorporation into the soil of organic debris that generates biocidal compounds during its decomposition. The aim of this study was to determine the in vitro herbicidal effect of biofumigation with Brassica juncea L. Czerniak (brown mustard) and Sinapis alba L. (white mustard), at the fructification stage, on germination and growth of seedlings of Anoda cristata (L.) Schltdl., Picris echiodes L. and Portulaca oleracea L. Two doses (10 and 40 g) of triturate plant material from each mustard species were placed separately in plastics recipients. Petri dishes with moist paper, which contained 50 seeds of the weed species, were placed on top of the plant material. It was incubated at 24 ± 2°C, with a photoperiod of 12h/12h light-dark. After 8 days, the biofumigant material was extracted and incubation was continued until day 21. Brassica juncea, at the two doses tested, inhibited significantly the germination of the three weed species. Sinapis alba only inhibited the germination of A. cristata and P. echiodes at dose of 40 g; however, in all treatments slowed significantly the growth of seedlings of the three weed species. These in vitro results suggest that B. juncea would have greater potential than S. alba for biocontrol of the weeds A. cristata, P. echiodes and P. oleracea.

Caracterização do hábito de frutificação do mirtileiro cultivado na mesorregião de Pelotas/RS, Brasil

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Characterization of Blueberries Fructification habits grown in the middle region of Pelotas/RS, Brazil Revista de la Facultad de Agronomía; vol. 115, no. 1 O mirtileiro é uma espécie exótica para o Brasil, tendo sido introduzida sem estudos prévios quanto o comportamento da planta para as condições de cultivo do sul do Brasil. Neste sentido objetivou-se caracterizar o comportamento das cultivares Climax, Blugem e Powerblue, do grupo rabbiteye, frente à diferenciação das gemas floríferas em diferentes comprimentos de ramos, para as condições de cultivo da mesorregião de Pelotas, RS. O delineamento experimental foi inteiramente ao acaso, conduzido sob esquema fatorial 2 x 2 (comprimento do ramo x ano). A coleta dos dados foi realizada, por duas safras consecutivas, 2012/2013 e 2013/2014, em ramos longos e curtos. Sob os ramos foram realizadas contagens do número de gemas floríferas e vegetativas, bem como a posição destas no ramo, ainda avaliando-se o diâmetro da base e do topo do ramo, além do seu comprimento. O número de níveis de gemas floríferas intercaladas as vegetativas, a cultivar Powderblue possui três níveis, quatro para Bluegem e cinco a Climax. O maior número de gemas floríferas foi verificado no primeiro nível, 9,3 e 5,0, respectivamente, nos ramos longos e curtos. O número total de gemas floríferas foi de 10,27 gemas para ramos longos e de 6,33 gemas para ramos curtos.; The Blueberry tree is an exotic species in Brazil which has been inducted without any previous studies regarding its behavior to plantations conditions in the south of Brazil. In this way it was aimed to characterize the cultivar Climax behavior, Bluegem and Powderblue, from rabbiteye group, related to the differentiation of flowered gems in different sizes of branches, to different kinds of growing in the middle region of Pelotas, RS. The underlying experiment was completely made by chance, conducted under factorial scheme 2 vs 2 ( branch length vs year). The data collection data was made during two consecutive harvests, 2012/2013 and 2013/2014, in long branches and short. Under the branches were made counting of vegetates and flowered gems as well as their position in the branches and also evaluating the branch diameter from the bottle to the top, and its length. Regarding the level numbers of flower gems interspersed to vegetates, the cultivar Powderblue has tree levels, four to Bluegem and five to Climax. The greatest number of flowered gems was verified in the first level, 9.3 and 5.0 respectively, in long and short branches. The total number of flower gems was 10.27 gems to long branches and 6.33 to short branches.

Color, cenizas y capacidad antioxidante de mieles de la provincia de Buenos Aires, Argentina

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Colour, ash and antioxidant activity of honey from Buenos Aires province, Argentina Revista de la Facultad de Agronomía; vol. 115, no. 1 En el presente trabajo se caracterizaron 40 muestras de mieles de la provincia de Buenos Aires, Argentina, provenientes de siete regiones geográficas: Provincia Paranaense, Provincia del Espinal distrito del Talar y distrito del Caldén, Provincia Pampeana distrito Oriental, distrito Occidental y distrito Austral, y Provincia del Monte. El análisis palinológico demostró que la mitad de las mieles correspondían a mieles monoflorales. Se evaluó la capacidad antioxidante por medio de los ensayos de DPPH y FRAP, el contenido de fenoles totales (Folin), cenizas y color (Pfund) en función del origen floral y la procedencia geográfica. Se encontraron diferencias significativas en la actividad antioxidante, el contenido de cenizas, el color y el contenido de fenoles totales en muestras de miel de distintas regiones (p ≤ 0,05). Sin embargo, mieles con distinto origen floral sólo presentaron diferencias significativas en el contenido de cenizas. Los resultados indican que la las mieles de Buenos Aires podrían ser caracterizadas mejor por su origen geográfico que por su origen floral.; In the present work 40 honey samples from 7 different regions of Buenos Aires province, Argentina, were analyzed: Paranaense province, Espinal province: Talar and Caldén districts, Pampeana province, Oriental, Occidental and Austral districts and finally Monte Province. The palinological analysis showed that half of the samples were from monofloral honeys. Samples were characterized by their antioxidant capacity (DPPH and FRAP), total phenolic content (TPC), ash and colour. Samples from different regions showed significant differences among their antioxidant activity (DPPH), ash and colour (p ≤ 0,05). However, samples from different botanical origin only showed significant differences in their ash content (p ≤ 0,05). The present results suggest that Buenos Aires honeys could be better classified by their geographical origin rather than their botanical origin.

In vitro propagation of Lippia integrifolia (Griseb.) Hier. and detection of genetic instability through ISSR markers of in vitro-cultured plants

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Propagación in vitro de Lippia integrifolia (Griseb.) Hier. y detección de variación genética en vitroplantas a través del uso de ISSRs Revista de la Facultad de Agronomía; vol. 115, no. 1 Aromatic and medicinal plants have been traditionally harvested from the wild and, in Argentina, they have been exploited without any major limitation. In vitro plant propagation is an easy and inexpensive method to obtain huge amounts of plants in a short period. This practice is relevant for the propagation of valuable and endangered species, facilitating their conservation and germplasm breeding. Since tissue culture can induce genetic and phenotypic variations, collectively termed “somaclonal variation”, molecular markers have been used to determine the genetic variability induced. In this work, successful propagation of Lippia integrifolia (Gr.) Hie (“incayuyo”) was achieved with 2,2 μM of bencylaminopurine added to the Murashige-Skoog medium. Shoots were recovered from the development of axillary meristems and through de novo shoots regeneration from organogenic calluses. Regenerated plants were taken to an experimental trial nearby their natural habitat for their evaluation in an agricultural environment. From the moment phenotypic variants started to appear in the ex vitro regenerated plants, the genetic variability of both kinds of recovered materials was studied by intersimple sequence repeats. Thirteen markers were used, detecting polymorphisms with all the primers tested in both types of recovered plants. The existence of polymorphisms implies that the genetic stability must be evaluated in all the ex vitro recovered plants. The protocol developed here is the first step to be applied in biotechnological techniques employed to improve the quality of “incayuyo”. Moreover, this is the first work employing molecular markers in L. integrifolia.; Las plantas aromático-medicinales han sido tradicionalmente recolectadas de su medio natural, y en Argentina, han sido explotadas sin ninguna limitación. La propagación in vitro de plantas es un método fácil y económico para obtener grandes cantidades de plantas a corto plazo. Esta práctica es relevante para la propagación de especies valiosas y en peligro de extinción, facilitando su conservación y mejoramiento. Debido a que el cultivo de tejidos puede inducir variaciones genéticas y fenotípicas, comúnmente denominadas "variación somaclonal", los marcadores moleculares se han utilizado para determinar esta variabilidad. En este trabajo, se logró la propagación de Lippia integrifolia (Gr.) Hie ("incayuyo") con 2,2 μM de bencilaminopurina añadido al medio Murashige-Skoog. Los brotes fueron recuperados a partir del desarrollo de meristemas axilares y a través de la generación de brotes de novo regenerados a partir de callos organogénicos. Las plantas regeneradas fueron llevadas a un campo experimental, cercano a su hábitat natural, para su evaluación. Dado que se detectaron variantes fenotípicas en las plantas regeneradas, se estudió la variabilidad genética de los dos tipos de materiales recuperados a través de microsatélites anclados. Se utilizaron trece marcadores, detectándose polimorfismos con todos los iniciadores ensayados en ambos tipos de plantas recuperadas. La existencia de polimorfismos implica que la estabilidad genética debe ser evaluada en todas las plantas recuperadas. El protocolo aquí desarrollado es el primer paso para la aplicación de biotécnicas para el mejoramiento de “incayuyo". Por otra parte, este es el primer trabajo en L. integrifolia donde se emplean marcadores moleculares.

Cambios en la comunidad de arañas (Arachnida: Araneae) en períodos de barbecho y de cultivos de soja en el Norte de Santa Fe, Argentina

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Changes in the community of spiders (Arachnida: Araneae) in fallow periods and soybean crops in northern Santa Fe, Argentina Revista de la Facultad de Agronomía; vol. 115, no. 1 El objetivo de este trabajo fue demostrar si existe un patrón de cambio en la comunidad de arañas y a nivel de gremios en los ciclos de sucesión barbecho (B)/soja (S) (B1/S1/S2/B2) y observar si los períodos de barbecho sirven como refugio para que la comunidad de arañas se pueda restablecer en períodos de cultivo. El estudio se realizó en la Estación Experimental Agropecuaria (EEA-INTA) Reconquista (Santa Fe-Argentina), en lotes que presentaban la misma sucesión de cultivo/barbecho durante 2009/2010. En cada período las arañas fueron recolectadas mediante trampas de caída y aspirador. Se recolectaron un total de 4439 arañas en 23 familias y 148 especies/morfoespecies. El cultivo de soja presentó mayor abundancia de arañas (B1= 512; S1= 1289; S2= 1363; B2= 1275) y riqueza de especies (B1=79, S1=92, S2=89; B2=80) que los períodos de barbecho. La abundancia/trampa mostró diferencias significativas entre los períodos de barbecho (B1-B2) y la riqueza de especies/trampa entre B1-S1 y B1-B2. Los valores de disimilitud mostraron una disminución desde B1hacia B2 donde las familias Lycosidae, Araneidae, Linyphiidae, Philodromidae, Pisauridae y Tetragnathidae contribuyen en alta proporción (superior 37%). Siete gremios estuvieron presentes (Cazadoras deambuladoras, Cazadoras corredoras sobre el suelo, Tejedoras de telas orbiculares, Otras cazadoras, Tejedoras de telas en sábanas, Tejedoras de telas espaciales y Especialistas) mostrando su abundancia diferencias significativas en los diversos momentos del período estudiado. Este trabajo demuestra que períodos de descanso del cultivo constituyen una adecuada herramienta de rotación para tener presente al momento de implementar estrategias de manejo en cultivos de soja.; The aim of this study was to demonstrate whether there is a pattern of change in the community and guilds of spider in a succession of fallow and soybean crops (B1/S1/S2/B2). Also, to analyze whether fallow periods would serve as a refuge for the community of spiders and their recovery during cropping periods. The study was carry out in the Research Station of INTA Reconquista, (Santa Fe-Argentina), underfield conditions with similar succession crop/fallow during 2009/2010.In each period, spiders were collected using pitfall-traps and suction samples. We recorded 4439 spiders from 23 family and 148spp/morphospecies. The highest abundance of spiders (B1= 512; S1= 1289; S2= 1363; B2= 1275) and richness of species (B1=79, S1=92, S2=89; B2=80) were found during the cropperiods compared to fallow periods. The abundance per tramps showed significant differences between fallows periods (B1-B2). Richness of species per tramp was also significant among B1-S1 and B1-B2.Dissimilarity values showed a decrease from B1 to B2 where families Lycosidae, Araneidae, Linyphiidae, Philodromidae, Pisauridae and Tetragnathidae had the highest proportion (upper 37%). Seven guilds were found (Ambush hunters, Ground hunters, Orb web weavers, Other hunters, Sheet web weavers, Space web weavers and Specialists) and showed abundance significant differences in different moments between periods. This work demonstrates that resting periods constitute an appropriate crop rotation tool to keep in mind when implementing management strategies in soybean crops.

Atributos físicos do solo e matéria orgânica sob dois manejos e efeito residual da aplicação de calcário e gesso agrícola

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Physical attributes and organic matter of a soil cultivated with corn under two managements and residual effect of limestone and gypsum Revista de la Facultad de Agronomía; vol. 115, no. 1 O uso do calcário e gesso agrícola e o manejo do solo podem influenciar seus atributos. Neste contexto, o objetivo do presente trabalho foi avaliar a influência do manejo, calcário e gesso agrícola sobre as propriedades físicas e Matéria Orgânica no Solo após safra de milho segundo cultivo. O experimento foi conduzido em Chapadão do Sul-MS, sendo disposto no delineamento de blocos casualizados com os fatores arranjados em parcelas subdivididas. As parcelas receberam os níveis dos fatores sistema de manejo convencional e direto e as subparcelas as aplicações de calcário e gesso agrícola (Controle, Calcário (3,563 Mg ha^-1), Gesso (2 Mg ha^-1), Calcário dose recomendada + Gesso (3,563 Mg ha^-1 + 2 Mg ha^-1), Calcário metade da dose recomendada + Gesso (1,781 Mg ha^-1 + 2 Mg ha^-1) e Calcário dobro da dose recomendada + Gesso (7,126 Mg ha^-1 + 2 Mg ha^-1), com quatro repetições. A densidade do solo e a resistência à penetração não foram influenciadas pelo sistema de cultivo e sistema de condicionamento do solo, após 03 anos de implantação do experimento. O sistema de manejo convencional com efeito residual da gessagem proporcionou maior valor de porosidade total (0,545 m³ m^-3), macroporosidade (0,053 m³ m^-3), microporosidade (0,492 m³ m^-3), e matéria orgânica (15,0 g kg^-1), na camada de 0,10-0,20 m. O sistema de semeadura direta com efeito residual da aplicação de calcário dose recomendada mais gesso agrícola proporcionou maior teor de matéria orgânica (15,0 g kg^-1) na camada de 0,0-0,10 m.; The use of limestone and gypsum and soil management can influence its attributes. In this context, the aim of this study was to evaluate the influence of management, limestone and gypsum on soil attributes and corn yield second crop. The experiment was conducted in Chapadão do Sul- (Brazil), being arranged in a randomized block design, in split plot arranged factors. The plots received the levels of conventional management and no-tillage and the split applications of lime and gypsum (Control, Limestone (3.563 Mg ha^-1), Gypsum (2.0 Mg ha^-1), Limestone recommended dose + Gypsum (3.563 Mg ha^-1 + 2.0 Mg ha^-1), Limestone half the recommended dose + Gypsum (1.781 Mg ha^-1 + 2.0 Mg ha^-1) and Limestone twice the recommended dose + Gypsum (7.126 Mg ha^-1 + 2.0 Mg ha^-1), with four replications. The soil bulk density and penetration resistance were not influenced by cropping systems and soil conditioning system, after 03 years of experiment deployment. The management system conventional residual effect of gypsum provided greater values of total (0.545 m³ m^-3), macro- (0.053 m³ m^-3), and micro- (0.492 m³ m^-3) porosity, and organic matter (15.0 g kg^-1), in the 0.10-0.20 m layer. No-tillage with residual effect of limestone and gypsum recommended dose provided greater content of organic matter (15.0 g kg^-1), in the layer of 0.0 to 0.10 m.

Resistência de biótipos de azevém ao herbicida iodosulfurom-metílico sódio e herbicidas alternativos para o controle

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Ryegrass biotypes resistant to iodosulfuron methyl-sodium herbicide and herbicides alternatives to the control Revista de la Facultad de Agronomía; vol. 115, no. 1 Sementes de biótipos suspeitos de resistência ao iodosulfurom foram coletadas em lavouras do Rio Grande do Sul (RS/Brasil) objetivando identificar o nível de resistência, metabolismo, atividade da enzima ALS e herbicidas alternativos para o controle. O nível de resistência para os biótipos resistentes (Joi e Col) e suscetível foi avaliado com 13 doses do herbicida iodosulfurom (0 à 384 g i.a ha^-1), aplicadas no estádio vegetativo de 3-4 folhas. A metabolização foi avaliada pela aplicação de malathion, inibidor das izoenzimas P450. Em laboratório foi avaliada a sensibilidade da ALS dos biótipos a diferentes concentrações do iodosulfurom (0 à 500 μM). Herbicidas alternativos para controle do azevém resistente foram avaliados em dois experimentos (herbicidas pré-emergentes ou pós-emergentes). De acordo com os resultados para controle equivalente dos biótipos resistentes são necessárias doses de iodosulfurom superior a 10 (Col) e 8 (Joi) vezes à quela necessária para o biótipo suscetível. Para a redução de 50% da MMSPA dos biótipos resistentes são necessárias doses 6 (Col) e 8 (Joi) vezes maiores do que as necessárias para o biótipo suscetível. A metabolização por inibição das P450 não é o mecanismo responsável pela resistência dos biótipos avaliados. A concentração de herbicida que reduz 50% da atividade da ALS do biótipo Col é semelhante ao Susc, no entanto, o biótipo Joi apresenta baixa inibição. Os herbicidas glifosato e cletodim apresentam-se como herbicidas alternativos para controle do biótipo resistente Col, resistente ao iodosulfurom, e o herbicida cletodim para o biótipo Joi. Na pré-emergência os herbicidas imazapir + imazapique, pendimentalina, clomazona, metribuzim, atrazina e S-metolacloro controlaram eficientemente os biótipos avaliados.; Seeds biotypes suspected of resistance to iodosulfuron were collected in crops at Rio Grande do Sul (RS/Brazil) state aiming to identify the resistance level, metabolism, ALS enzyme activity and alternative herbicides to control. Was evaluated resistance level of resistant (Joi and Col) and susceptible biotypes with thirteen increasing rate of the herbicide iodosulfuron (0 to 384 g ai ha^-1), sprayed in the vegetative stage of 3-4 leaves. Was assessed the metabolizing by the application of malathion, an inhibitor of P450 izoenzimas. Was evaluated the sensitivity of the ALS enzyme from different biotypes to iodosulfuron concentrations (0 to 500 mM) in laboratory. Were evaluated alternative herbicides to control of resistant ryegrass, belonging to different mechanisms of action in two trials (pre-emergence and post-emergent herbicides). According to results to equivalent control to the resistant biotypes are necessary iodosulfuron rates 10 (Col) and 8 (Joi) times higher that required to the susceptible biotype. To reduction of the MMSPA in 50% of resistant biotypes are required 6 (Col) and 8 (Joi) times higher rates than rate required for the susceptible biotype. The metabolism by inhibition of the P450 is not the mechanism responsible to the resistance in Col and Joi biotypes. The herbicide concentration that reduces 50% of ALS enzyme activity to Col biotype is similar to Susc, however, has little Joi biotype inhibition. The glyphosate and clethodim herbicides are shown as alternative to control the Col resistant biotype to iodosulfuron herbicide, and the clethodim herbicide to biotype Joi. Were efficiently controlled all biotypes evaluated with the herbicides imazapyr + imazapic, pendimethalin, clomazone, metribuzin, atrazine and S-metolachlor in pre-emergency.

Parâmetros físico-químicos, avaliação microbiológica e sensorial de geleias de laranja orgânica com adição de hortelã

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Physical-chemical parameters, microbiological and sensory evaluation of organic orange jellies whit addition of mint Revista de la Facultad de Agronomía; vol. 115, no. 1 O presente trabalho teve como objetivo desenvolver, avaliar a qualidade físico-química, microbiológica e sensorial de geleias de laranja orgânica com adição de hortelã. A formulação foi feita por meio de dois tratamentos: com e sem adição de hortelã. Os frutos para estudo foram coletados em Guaraciaba do Norte-CE, submetidos a análises de cor, sólidos solúveis (°Brix), acidez titulável (%), pH e vitamina C (mg. 100g^-1), análises microbiológicas como leveduras, coliformes e presença ou ausência de Salmonella spp. O produto final foi submetido à prova de esterilidade comercial e análise de aceitação sensorial, com 60 provadores para os atributos de cor, sabor, aroma e impressão global do produto utilizando uma escala hedônica e de ordenaçãopreferência. Para bolores e leveduras obtiveram-se < 10 UFC g^-1 para os dois produtos. As contagens de coliformes a 45 ºC foram inferiores a 10 NMP g^-1 para as duas geleias. Constatou-se ausência de Salmonella spp. em 25 g de amostra, para os dois produtos testados, em conformidade com a legislação vigente. Os resultados das análises físico-químicas revelaram maiores alterações nas geleias de laranja sem adição de hortelã, evidenciadas por meio das coordenadas L*, a* e b*. Entretanto, a geleia de laranja com hortelã se sobressaiu com valores médios maiores em quase todos os atributos avaliados. Os resultados da análise sensorial apontaram que a geleia comum obteve uma melhor aceitação e foi mais preferida significativamente em relação à geleia adicionada de hortelã, por parte dos consumidores. Portanto, os dois produtos aqui apresentados possuem qualidades físico-químicas, microbiológicas e sensoriais satisfatórias, podendo ser uma alternativa viável de aproveitamento do fruto, com potencial para comercialização.; This study aimed to perform physical-chemical analysis, microbiological and sensory acceptance of organic orange jellies with mint. The formulation was made using two different treatments: one with and one without the addition of mint. The fruit for this study were collected in Guaraciaba North-CE, submitted to analysis of color, soluble solids (°Brix), titratable acidity (%), pH and vitamin C (mg. 100 g^-1), microbiological analysis as yeast, coliforms and verification of the presence of Salmonella spp. The elaborate product was submitted to commercial sterility test and analysis of sensory acceptance, with 60 tasters for the attributes of color, aroma, flavor and overall impression of the product using a hedonic scale and ordering preferences. For mold and yeast were obtained < 10 UFC g^-1 for the two products. Coliforms at 45 ºC were below 10 NMP g^-1 for the two jellies. It was found Salmonella spp. in 25 g sample for the two products tested in accordance with current legislation. The results obtained in the physicochemical analysis have revealed higher changes in orange jellies without addition of mint, evidenced by the coordinates L*, a* and b*. However, the orange jelly with mint stood out with higher mean values in almost all attributes evaluated. The results of the sensory analysis showed that the common jelly obtained a better acceptance and has been significantly most preferred over the jelly added with mint, by consumers. Therefore, the two products presented here have physical-chemical, microbiological and sensory satisfactory and may be a viable alternative to use of the orange fruit, with high potential for commercialization.

Influência do manejo da altura de lâmina de água e densidade de semeadura nos componentes de produção do arroz no sistema de cultivo pré-germinado

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Influence of the management blade height of water and seeding rate on yield components the rice in the crop pre-germinated system Revista de la Facultad de Agronomía; vol. 115, no. 1 A economia da água é atualmente uma das principais fontes de estudo da lavoura arroz irrigado no Rio Grande do Sul. Em busca do aumento da capacidade produtiva, no sistema de cultivo pré-germinado, se faz necessário um estudo aprofundado da influência de técnicas específicas como a altura de lâmina de água e a densidade de semeadura. O objetivo deste trabalho é determinar a influência da altura da lâmina de água (1, 6, 11 e 16 cm) e de três densidades de semeadura (80, 120 e 160 kg ha-1) nos componentes de produção e produtividade da cultivar IRGA 425 no município de Faxinal de Soturno, Rio Grande do Sul. Os resultados apontam que os componentes de produção da cultivar IRGA 425 apresentaram influência causada pelas diferentes alturas de lâmina de água e densidades de semeadura. A maior produtividade foi obtida com 6 cm de profundidade de água e uma densidade de semeadura de 80 kg ha-1.; Water-saving irrigation is a major source of study for irrigated rice crops in Rio Grande do Sul. In search of increased productivity in pre-germinated cropping system, is necessary a detailed study of the influence of specific techniques as the height of the water blade and seeding rate. The objective of this study is to determine the influence of the water blade height (1, 6, 11 and 16 cm) and three seeding rates (80, 120 and 160 kg ha-1) in the yield components of cultivar IRGA 425 in the Faxinal of Soturno city, Rio Grande do Sul. The results indicate that the yield components of cultivar IRGA 425 showed the influence caused by the different water blade heights and seeding rates. The highest productivity was obtained with 6 cm of water blade and a seeding rate of 80 kg ha-1.

Calidad de semillas de especies nativas del bosque andino patagónico de la provincia de Chubut y su importancia para la producción de plantines

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Seed quality of native species of Patagonian forests of the province of Chubut and its importance for seedlings' production Revista de la Facultad de Agronomía; vol. 115, no. 1 El potencial de una semilla para desarrollar una plántula es conocido como calidad de la semilla y es estimada analizando sus características físicas y biológicas. El objetivo de este trabajo fue caracterizar la calidad de semillas de especies nativas recolectadas por el programa de cosecha de la provincia del Chubut. Se utilizó para ello la metodología indicada por las Reglas Internacionales de Análisis de Semillas. Se analizaron 33 lotes de semillas de 12 especies de las familias Cupresaceae, Nothofagaceae, Celastraceae, Proteaceae y Anacardiaceae. El valor promedio de la capacidad germinativa para cada familia fue de 51, 7, 8, 64 y 63 %, respectivamente. Los resultados se ubican en los rangos de valores publicados principalmente en Chile. Si bien las especies analizadas presentan potencialidad para programas de restauración y producción, la periodicidad en la semillazón y la calidad de las semillas podrían condicionar su desarrollo. Entre las especies más importantes, el ciprés de la cordillera (Austrocedrus chilensis (D. Don) Pic. Ser. et Bizzarri), presenta de buena a muy buena calidad de sus semillas. No sucede lo mismo con los Nothofagus, especialmente con la lenga (Nothofagus pumilio (Poepp. et Endl.) Krasser) que presenta temporadas sin producción de semillas o con producción de baja a nula calidad. Es recomendable entonces incrementar la recolección considerando diversas áreas geográficas y aprovechando años de buena semillazón. Es necesario además avanzar en el conocimiento y la elaboración de protocolos de conservación de las semillas de cada especie para consolidar la viverización y el establecimiento de las especies nativas.; The potential for a seed to develop a seedling is known as seed quality, and is estimated by analyzing its physical and biological characteristics. The aim of this study was to characterize the quality of seeds of native species collected by the Harvest Seeds Program of Chubut Province in Patagonia, Argentina. The methodology used followed the International Rules of the Seed Testing Association. Thirty three seed lots of 12 species each, belonging the Cupresaceae, Nothofagaceae, Anacardiaceae, Celastraceae, and Proteaceae families, were analyzed. The germination average was 51, 7, 8, 64 and 63%, for each family, respectively. The results coincide with the range of values published for the same species in Chile. The species analyzed have potential for restoration and production programs; however, the periodicity of seed production and seed quality could condition their development. Among the most important species, cypress (Austrocedrus chilensis (D. Don) Pic. Ser. Et Bizzarri) presents seeds from good to very good quality. The Nothofagus species, by contrast, and especially lenga (Nothofagus pumilio (Poepp. Et Endl.) Krasser), presents years without seed production or of low quality. In order to increase seed stocks, it is advisable to increase the collection areas, taking also advantage of high seed production years. It is also necessary to advance in the knowledge of rules and protocols for conservation of seeds of each species to consolidate production and further native species establishment.

Influência da safra de verão e outono no dano de larvas da vaquinha em tubérculos de batata cultivadas em casa de vegetação

Fri, 01 Jan 2016 00:00:00 GMT

Articulo Influence of summer and fall harvest in larvae damage caused in tubers cultivated in greenhouse Revista de la Facultad de Agronomía; vol. 115, no. 1 São vários os segmentos que se beneficiam da bataticultura, consumidores, agricultores, pesquisadores, setor produtivo, entre outros, tornando-a um dos alimentos mais consumidos por suas qualidades nutricionais. Um dos fatores limitantes à produtividade da cultura da batata está intimamente ligado à sua suscetibilidade a insetos, sendo os principais danos ocasionados por larvas de Diabrotica speciosa (Germar, 1824) (Coleoptera: Chrysomelidae). O objetivo deste trabalho foi avaliar a influência das safras de verão e outono no dano de larvas de D. speciosa em tubérculos de batata cultivados em casa de vegetação. As cultivares Agata e BRS Clara foram infestadas com as densidades de 0, 5, 15, 30 e 40 larvas/planta nas duas safras. O delineamento utilizado foi inteiramente ao acaso, com quatro repetições, contendo uma planta por vaso. Os danos foram mais expressivos na safra de verão para ambas as cultivares.; Many segments are benefited with potato growing: consumers, farmers, researchers, the productive sector, among others, making it one of the most consumed food items due to its nutritional qualities. One of the most limiting factors for the productivity of potatoes is closely connected to its susceptibility to insect, in which the main damages are caused by the Diabrotica speciosa (Germar, 1824) (Coleoptera: Chrysomelidae) larvae. The purpose of this work was to assess the influence of the summer and fall harvests in larvae damage caused in tubers cultivated in greenhouses. The cultivars Agata and BRS Clara were infested with the densities of 0, 5, 15, 30 and 40 larvae/plant in the two harvests. The outlining used was totally by chance, with four repetitions, with one plant per vase. Thus, the damages were more serious in the summer harvest for both cultivars.