In vitro plant regeneration from cotyledonary nodes of recombinant inbred lines of lentil

An efficient and reproducible in vitro regeneration protocol for lentil was developed. For shoot regeneration, cotyledonary node explants of ten elite genotypes were cultured in an inverted orientation on different shoot regeneration media that consisted of Murashige and Skoog (MS) medium supplemented with 1mgL -1 6-benzylaminopurine (BAP) (M1), 1mgL -1 BAP+0.45mgL -1 indole-3-acetic acid (IAA) (M2), and 2mgL -1 BAP (M3). High percentages of shoot regeneration ranging from 80 to 100% on M1 and M3 media and from 50 to 100% on M2 medium were induced. M1 was the most efficient shoot regeneration medium for most genotypes tested. For rooting, in vitro and in vitro-in vivo methods were used. Low and variable rooting percentages ranging from 0 to 45% were recorded with in vitro-in vivo method. Efficiency of rooting on in vitro medium varied depending on the medium in which shoots had been previously regenerated and the genotype tested. When M1 medium was used, high rooting percentages (over 40%) for most genotypes except for microsperma genotypes were found. When the 10 genotypes were screened for good regeneration performance using M1 medium, 2 main clusters and 3 subgroups within one of the clusters were formed based on similarities respect of the number of regenerated shoots per explant and rooting percentages. Subgroup 1 composed by A1146 genotype produced the highest number of shoots per explant (6.17 shoots) and a high rooting percentage (60%) so was selected for further transformation and use as a potential commercial variety.Fil: Bermejo, Carolina Julieta. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Espósito, María Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cravero, Vanina Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: López Anido, Fernando. Universidad Nacional de Rosario; ArgentinaFil: Cointry Peix, Enrique Luis. Universidad Nacional de Rosario; Argentin

Differences in seed dormancy associated with the domestication of <i>Cucurbita maxima</i> : Elucidation of some mechanisms behind this response

This work presents the results of physiological studies developed to understand modifications linked to the reduction of seed dormancy provoked by domestication processes. The experiments performed compared wild and domesticated Cucurbita subspecies and their hybrids developed by reciprocal crossings. Seeds of two accessions of the wild subspecies presented dormancy, but it was largely reduced in seeds from the domesticated genotype, and partially reverted in hybrids, especially in those obtained when the domesticated genotype was used as the mother plant. In addition, naked embryos of all subspecies did not display dormancy when incubation was performed at 28°C, but embryo germination was progressively reduced only in the wild genotype under decreasing incubation temperatures (22 and 16°C). In the embryos, abscisic acid (ABA) concentrations were similar in both domesticated and wild subspecies, whereas in the seed coat, it was threefold higher in the wild subspecies. The naked embryos from the wild subspecies were far more responsive to ABA than those from the domesticated subspecies. These results indicate that dormancy in the wild subspecies is imposed by the seed coat tissues and that this effect is mediated by their high ABA content and the sensitivity of the embryos to ABA. These physiological aspects were apparently removed by domestication along with the temperature-dependent response for germination.Instituto de Fisiología VegetalLaboratorio de Etnobotánica y Botánica AplicadaFacultad de Ciencias Naturales y Muse

Application of gibberellic acid in globe artichoke

En el Cinturón Hortícola de Rosario (33º 1' L.S y 60º 59' L.O.) la producción de alcaucil (Cynara scolymus L.) se concentra desde agosto a octubre. Para incrementar la rentabilidad debería adelantarse la fecha de cosecha a los meses de mayores precios, lo que podría lograrse con la pulverización exógena de ácido giberélico (AG3). Se evaluó el comportamiento de cultivares agrupadas según su precocidad frente a la aplicación de AG3 y su efecto sobre el ingreso bruto. Se utilizó un diseño en bloques completos aleatorizados con dos repeticiones. Se aplicaron 50 ppm de AG3 en abril más 25 ppm en mayo de 1994 y 1995. El número de alcauciles por ha, peso promedio, diámetro y altura, rendimiento, peso medio del capítulo de primer rango, días a cosecha y días de cosecha, fueron analizados a través de un análisis de variancia a dos criterios de clasificación por año y en un análisis combinado de años. La aplicación de AG3 en 1994 anticipó la producción en 52 días para el Grupo I, 6 días para el II y sólo 3 días para el III, ampliándose los días de cosecha en 60, 8 y 3 respectivamente, mostrándose igual tendencia en 1995. No se produjeron modificaciones significativas en el resto de las variables para los dos años de ensayo. La aplicación de AG3 generó un ingreso bruto superior dependiendo su magnitud de los años evaluados y del grupo analizado.The production of globe artichoke (Cynara scolymus L.) in the Horticultural Rosary Belt (33º 1' S.L and 60º 59' W.L) is concentrated from August to October. In order to increase the profitability it is necessary to bring toward the crop date to the months of higher prices, which could be achieved with the pulverisation of exogenous gibberellic acid (GA3). The behaviour of cultivars grouped according to their precociousness as compared to the application of GA3 as well as effect on the gross revenue were evaluated. A randomised complete block design with two replications was used. Fifty ppm of GA3 in April supplemented with 25 ppm were applied in May of 1994 and 1995. The number of heads per hectare, the average weight, the head diameter and height, yield, the average weight of the first range head, days to crop and crop days, were analysed through an ANOVA with 2 classification criteria for each year and in a combined year analysis. The application of GA3 in 1994 brought the production 52 days forward for the group I, 6 days for group II and only 3 days for group III, extending the crop days in 60, 8 and 3 days, respectively, showing equal trend in 1995. There were no significant modifications for the rest of the variables in the two trial years. The application of GA3 generated an increase in gross revenue, depending on its magnitude, on the evaluated years and on the analysed group

Diversidad morfológica y molecular en Cucurbita maxima Duchesne ex Lam.

Cucurbita maxima Duch. es una especie de origen sudamericano que ha sido domesticada en una gran diversidad de formas y tipos de frutos. Los estudios previos han descrito y caracterizado conjuntos de materiales pero en forma parcial, no siempre incluyendo todos los representantes domesticados y el antecesor silvestre. En tal sentido el presente trabajo tiene como objetivo extender la caracterización morfológica y molecular a un conjunto amplio de entradas para contribuir al entendimiento de las relaciones entre las formas domesticadas entre sí y con las silvestres. Un conjunto de 171 entradas de Cucurbita, que abarcan tanto los grupos de cultivares propuestos para C. maxima (Zapallito, Zipinka, Turbante, Nugget, Buttercup, Moranga, Show, Hubbard y Banana), orígenes distintos, poblaciones de la subespecie silvestre (C. maxima ssp. andreana), entradas no asignadas a estos grupos de cultivares, así como también germoplasma de otras especies de Cucurbita: C. moschata, C. argyrosperma, C. ficifolia (domesticadas) y C. ecuadorensis (semidomesticada), fueron evaluadas para 39 caracteres cuantitativos de hábito de crecimiento, ciclo a antesis, hojas, tallos, pedúnculos, frutos, semillas y partición hacia la producción de fruto y semilla, como así también para 47 atributos cualitativos de los tipos de hoja, fruto, pulpa, semilla y planta. Además, en un subconjunto de las entradas se realizó un análisis molecular a partir de marcadores SRAP (Secuence related amplified polymorphism). La caracterización a campo se realizó con un diseño de dos repeticiones de seis plantas por cada entrada durante dos años de evaluación. Los atributos cuantitativos fueron sometidos a un análisis de la variancia y comparación de valores promedio, y todos los atributos (cuantitativos y cualitativos) fueron analizados en forma independiente y en conjunto con análisis multivariados de componentes principales, coordenadas principales, conglomerados y procrustes generalizado. Se encontró una significativa variación para todos los caracteres cuantitativos entre las entradas de C. maxima estudiadas. La partición de los cuadrados medios entre grupos de cultivares, definidos por atributos de color y forma de fruto, fue en general mayor que dentro de los grupos, lo que se traduciría en que los grupos también guardan cierta semejanza para otros caracteres. El estudio por atributos cualitativos reflejó una diferenciación entre los grupos de cultivares, donde algunos se caracterizan por ciertos atributos en particular. En el análisis de conglomerados se separaron las entradas de C. maxima ssp. andreana de las de las formas cultivadas, donde los grupos Zapallito y Zipinka tendieron a compartir el mismo clado. En el consenso de los caracteres cuantitativos y cualitativos hubo un agrupamiento entre Plomo, 3 Moranga y Hubbard, y entre Zapallito, Nugget y Zipinka. C. maxima ssp. andreana se diferenció de los representantes de C. maxima ssp. maxima. La entrada 129unk (Ovo de ganso) correspondiente a C. maxima ssp. maxima tomó una posición intermedia en la configuración. El análisis a través de los marcadores SRAP permitió separar a cada una de las especies fuera de grupo (C. moschata, C. argyrosperma, C. ficifolia y C. ecuadorensis) de entradas de C. maxima. Las entradas de C. maxima ssp. andreana se separaron de las de la ssp. maxima, a excepción de la entrada 129unk. Dentro de las forma cultivadas de C. maxima no hubo un claro agrupamiento por grupo cultivar, sí cierta tendencia por origen sobre todo en las entradas no asignadas a alguno de los grupos de cultivares. La distancia genética entre los grupos cultivados dentro de C. maxima ssp. maxima y la ssp. andreana fue mayor que entre los grupos. Dentro de los grupos, Banana, Zipinka, Hubbard, Moranga y Show presentaron la menor distancia genética promedio, y Buttercup la mayor. El consenso de los caracteres morfológicos y moleculares permitió distinguir cierta relación entre los grupos. Las entradas de Zapallito, Zipinka y Nugget se posicionaron más cerca entre sí. Lo mismo ocurrió entre los representantes de Show, Plomo, Hubbard y Moranga. C. maxima ssp. andreana se separó claramente, y la entrada 129unk se posicionó mas cerca de esta subspecie que de la ssp. maxima. Las otras especies de Cucurbita también se separaron de C. maxima. Se discuten los posibles centros de domesticación sudamericanos para la especie asociado a los grupos de cultivares.Cucurbita maxima Duchesne ex Lam. is a South American species that has been domesticated in a great diverse of fruit forms. Previous studies about germplasm diversity in this species have been conducted but not considering all the domesticated forms and the wild ancestor as well. In this sense, the present contribution aims to characterize a wide array of accesions in a way to undestand relationships among C. maxima cultivar groups and the wild form. Comparative field studies of 171 Cucurbita accesions selected among C. maxima cultivar groups (Zapallito, Zipinka, Turbante, Nugget, Buttercup, Moranga, Show, Hubbard and Banana), wild populations of C. maxima ssp. andreana, and outgroup species (C. moschata, C. argyrosperma, C. ficifolia and C. ecuadorensis) were evaluated for 39 quantitative characters: plant growth habit, flowering cycle, leaves, stem, peduncles, fruits, seeds, and partitioning to seed and fruit production; and 47 qualitative attributes of leaf type, fruit, pulp, seed and plant habit. Also a molecular analysis of SRAP markers (Secuence related amplified polymorphism) was conducted in a sample of accesions. Field comparison of two replicates of six plant per accesion were developed during two years. Quantitative traits data were subjected to an ANOVA and mean values comparison. All characters (quantitative and qualitative) were evaluated in an univariate and multivariate approaches, as well as principal component, principal coordinate, cluster and procrustes analyses. Significant variation among accesions were found for all quantitative attributes, and some cultivars groups were distinguished by specific qualitative characters. In the cluster analysis of C. maxima ssp. andreana populations were grouped apart from the cultivated forms, where Zapallito and Zipinka tended to group together. Consensus analysis of quantitative and qualitative characters grouped Plomo, Moranga and Hubbard; and Zapallito, Nugget and Zipinka. Cucurbita maxima ssp. andreana accesions were grouped apart from the cultivated forms of C. maxima ssp. maxima. The accesion 129unk of C. maxima ssp. maxima was placed intermediately between C. maxima ssp. andreana and ssp. maxima. Molecular analysis clearly separated outgroup species from C. maxima, and within this species, ssp. andreana was grouped apart from representative accessions of C. maxima ssp. maxima with the exception of 129unk. Among cultivated forms of C. maxima ssp. maxima the analysis did not reveal a clear assemblage according to cultivar group classification. Some accesions not assigned to a 5 specific cultivar group, were grouped according to their origin. Genetic distance between germplasm of C. maxima included in different cultivar groups and accessions of C. maxima ssp. andreana was greater than among cultivar groups themselves. Morphological and molecular characters consensus analysis grouped Zapallito, Zipinka, and Nugget accesions on one side, and Show, Plomo, Banana, Hubbard and Moranga accesions on the other side. Cucurbita maxima ssp. andreana was clearly separated from cultivated, and only accesion 129unk was closer to this subspecies than to C. maxima ssp. maxima representatives. Hipothesis about domestication centers associated to cultivars groups are discussed.Fil: Apellido, Nombre. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; ArgentinaFil.: López Anido, Fernando Sebastián. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentin

Cultivar-Groups in Cucurbita maxima Duchesne: Diversity and Possible Domestication Pathways

Domesticated Cucurbita has been remarked as one of the plant genera with the highest diversity in color, shape and fruit dimensions. Their economic and cultural values are related to the consumption of the mature or immature fruits, seeds, flowers, and to the use as decoration. The wild ancestor of C. maxima, the ssp. andreana has an actual scattered and disjointed distribution, associated with megafauna seed disperser syndrome. It was domesticated in South America around 9000–7000 years BP. The cultivar-group is a subspecific category for assembling cultivars on the basis of defined similarity. The work describes and pictures nine cultivar-groups for the species, Banana, Turban, Hubbard, Show, Buttercup, Zapallito, Plomo, Zipinka and Nugget. The molecular and a morphological join data analysis scatter biplot showed Turban and Buttercup in a central position, suggesting a first step in the domestication pathway associated with seed and immature fruit consumption; afterward, bigger bearing fruits groups were selected for their mature fruit flesh quality on one hand, and bush type, short day induction and temperate climate adaptation on the other hand. The striking domesticated Brazilian accession MAX24 intermediate between cultigens and ssp. andreana strengthens, in concordance with archeological remains, the possible domestication place of the species more easternward than previously believed

Combining Ability and Heterosis for Market Yield in Green Asparagus

In asparagus, current cultivars are mostly hybrids (known as clonal hybrids) derived from crosses between two parents, female and male, with good combining ability. Despite the fact that clonal hybrids have been obtained for more than 40 years, studies of the heterosis and combining abilities involved are limited. Similarly, there are no published studies regarding the association between genetic divergence and heterosis. In this sense, we evaluated two sets of diallel crosses including 12 accessions from 11 different origins for marketable green asparagus production. Parentals were also included as a way to assess heterosis. The variation for market yield was highly significant for both sets. Best parent heterosis was over 100% in four cases. The best experimental hybrid did not significant differ from the Atticus F1 all-male check. The general combining ability (GCA) and specific combining ability (SCA) were significant, with a relative greater contribution of the SCA than the GCA to the variation among crosses. The association between genetic distances and heterosis failed to be significant. The best experimental hybrids were obtained when UC157 and KBF (origins from the USA and the UK) were crossed to Argenteuil, Limburgia and Esp&aacute;rrago de Navarra (origins from France, the Netherlands and Spain)

Agronomic characters in asparagus of different ages and crop systems

Age and crop system effects on agronomic response were evaluated in 11 hybrids of Asparagus officinalis L. The experimental design was a complete randomized block with three replicates of 20 plants of 3 or 4 years old, conducted either in mounded soil over plants for blanched asparagus, or in raised beds without ridging for green asparagus. The highest mean values were obtained under the blanched production for days to harvest, market yield, total yield, spears number and the spear mean weight. However, under the green production, the rate of increment from first to second year was superior for market yield and total yield due to an augmented rate of increment of spears number. Type and year of production effects were similar for days to first harvest and spears mean weight, meanwhile days to 50% of sprout plot was affected mainly by the year of productionEl objetivo del trabajo fue evaluar el efecto de la edad de la planta y la respuesta a los manejos en 11 híbridos de espárrago (Asparagus officinalis L.). Se utilizó un diseño en bloques completos aleatorios con tres repeticiones de 20 plantas por parcela, con tres y cuatro años de edad, según dos sistemas de manejo: con surcos alomados para la producción de espárrago blanco y surcos sin alomar para espárrago verde. Con el manejo para espárrago blanco se obtuvieron mayores valores promedio para días a brotación, rendimiento de mercado, rendimiento total, número de turiones y peso promedio del turión. Sin embargo, la tasa de incremento del primer al segundo año de cosecha para rendimiento de mercado y rendimiento total resultó superior en el manejo verde debido a una tasa de incremento superior para número de turiones. Para días a brotación y peso promedio del turión, la respuesta debida al efecto del manejo y de la edad del cultivo fue similar, mientras que días al 50% de parcela brotada se vio afectada principalmente por la edad de la planta.Age and crop system effects on agronomic response were evaluated in 11 hybrids of Asparagus officinalis L. The experimental design was a complete randomized block with three replicates of 20 plants of 3 or 4 years old, conducted either in mounded soil over plants for blanched asparagus, or in raised beds without ridging for green asparagus. The highest mean values were obtained under the blanched production for days to harvest, market yield, total yield, spears number and the spear mean weight. However, under the green production, the rate of increment from first to second year was superior for market yield and total yield due to an augmented rate of increment of spears number. Type and year of production effects were similar for days to first harvest and spears mean weight, meanwhile days to 50% of sprout plot was affected mainly by the year of production

Caracterización de aspectos de calidad a cosecha de cinco híbridos de espárrago bajo dos sistemas de manejo

El espárrago es una hortaliza cuyo órgano de consumo es el tallo inmaduro llamado turión. En el manejo como verde el espárrago crece sobre la superficie del suelo, mientras que como blanco lo hace a través del mismo, pudiendo generar diferencias en la composición química y fisiológica de los materiales. El objetivo fue caracterizar aspectos de calidad, a cosecha, de cinco híbridos de espárrago bajo dos sistemas de manejo. El ensayo se realizó en la Facultad de Ciencias Agrarias, Zavalla, UNR. Como material experimental se utilizaron cinco híbridos clonales de espárrago obtenidos en el marco del programa de mejora establecido entre la Facultad y la EEA INTA Balcarce: Neptuno, Mercurio, Sureño, Lucero y Pampero. Como testigos comerciales: Argenteüil para el manejo como espárrago blanco y UC 157 F1 para manejo como espárrago verde. Para cada material se analizó la composición y calidad en 3 zonas diferentes: apical, media y basal. Las variables evaluadas fueron: fibra (%), sólidos totales (%), fenoles (mg.g-1de peso fresco), azúcares totales (mg glucosa.g de pf-1), pH, clorofila (microg.g-1de peso fresco) y actividad respiratoria (mg CO2.h-1.kgf-1). El ensayo se realizó en un DCA con tres repeticiones (de tres espárragos), por híbrido y zona de corte, analizado a través de un ANDEVA y prueba de Duncan. El contenido de fibra fue mayor en los espárragos blancos, destacándose Lucero por su menor contenido de fibra, la cual aumentó hacia la base del turión en todos los casos. Los sólidos totales manifestaron mayores valores en los espárragos verdes. Sureño presentó el mayor nivel cultivado como blanco y como verde Sureño y Neptuno. Para ambos manejos del cultivo y dentro de cada híbrido, fue mayor el contenido en la zona apical. El contenido de fenoles en los espárragos blancos fue mayor; el mayor valor lo presentó Sureño como blanco y UC 157 F1 como verde y en todos los casos fue mayor en la parte apical. El contenido total de azúcares fue mayor en Pampero, Mercurio, Argenteüil y Neptuno como blanco y en Pampero y UC 157 F1 como verde. En todos los casos la parte apical manifestó el menor valor. El pH presentó valores similares, con mayor acidez en la parte basal. La tasa respiratoria fue superior en los híbridos verdes. La cantidad de clorofila fue mayor en la zona apical. En el manejo como blanco se observó un mayor contenido de fenoles y una menor tasa respiratoria, mientras que en el manejo como verde un mayor contenido de sólidos totales y menor porcentaje de fibra.Asparagus is a vegetable grown for its edible organ, which is an immature stalk called spear. When cultivated for green asparagus, the spears grow mostly over soil level; meanwhile, when grown for blanched or white asparagus, they grow across the mounted soil. These differential conditions may generate changes in the chemical and physiological composition of the spears. The objective of the present work was to characterize quality harvest aspects in five asparagus hybrids evaluated under two cultivation systems. The field experiment was conducted at the Agronomy Faculty, Rosario´s National University (UNR), located at Zavalla. The plant material consisted in five asparagus hybrids, Neptuno, Mercurio, Sureño, Lucero and Pampero, developed by the Agronomy Faculty, UNR, and the EEA INTA Balcarce, in a conjunct breeding program. As commercial checks for white and green production Argenteüil and UC 157 F1 were used respectively. In each material, quality and composition were analyzed in three differential portions of the spear: apical, medium, and basal. The evaluated characters were: fiber content (%), total solids (%), phenols (mg.g-1 fresh weight), total sugars (mg glucose g fresh weight), Ph, chlorophyll (microg g-1 fresh weight) and respiratory activity (mg CO2 h-1 fresh weight). The experiment was conducted in a randomized design with three repetitions of three spears each, considering hybrids and portions of the spear as treatments. Data were first subjected to an analysis of variance and then to a Duncan´s multiple mean comparison test. In general terms fiber content was higher in blanched asparagus than in green asparagus, and in the basal portion than in the rest. Lucero presented the highest values for fiber content. Total solids were higher under green asparagus production and along the apical portion than under white production, and along medium and basal portions of the spear. Sureño for white and Neptuno and Sureño for green spears showed the highest content in total solids. Phenols were higher either under blanched and in the apical portion of the asparagus than under green and medium or basal portions of the asparagus. Sureño for white and UC 157 F1 for green production presented the highest phenols content. Conversely under both productions, total sugar was lower in the apical portion than in the rest of the spear. For this character, blanched asparagus hybrids Pampero, Mercurio, Argenteüil and Neptuno; and green hybrids Pampero and UC 157 F1 presented the highest values. Ph values were similar in general terms, with a trend towards higher acidity in the basal portion; meanwhile chlorophyll content was superior in the apical portion of the spear. Respiratory activity was higher in green asparagus than in white asparagus. Under white production a higher phenols and a lower respiratory activity was observed in comparison to green production. Conversely green spears showed a higher total solids and lower fiber percentage than white asparagus