In vitro culture of Bambara groundnut [Vigna subrerranea (L.) Verdc., Favaceae ]: Effect of plant growth regulators, explant type and genotype on callus induction and differentiation

A technique was developed to induce callus formation and differentiation using leaf, petiole and root explants from Bambara groundnut [Vigna subterranea (L.) Verdc.]. The combinations and concentrations of differentgrowth regulators were shown to be critical factors in the frequency of callus formation, as well as, in the potential for callus differentiation. It was established that the best responses in callus induction (75 %) wereobtained from petiole on a MS (Murashige and Skoog, 1962) basal medium, supplemented with 3 -5 mg/l N-benzylaminopurine (BAP) + 0.5 mg/l á-naphthaleneacetic acid (NAA). Callus growth (GI) was moresignificant with Ci1 (3.52) and Ci4 (2.76) landraces, while root formation was especially observed with the Ci3 (24.81 %) landrace. Here, for the first time, induction of embryogenic and organogenic callus from petiole,leaf and root of Vigna subterranea (L.) was reported. Both adventitious buds and somatic embryos were initiated after 3 months of subculture on a callus induction medium containing 3-5mg/l BAP + 0.1 -0.5 mg/l ANA. Somatic embryogenesis (50 - 68 %) occur more frequently than organogenesis(11 - 27 %). Un protocole a ete developpe pour induire la formation de cals, a partir des explants de feuille, de petiole et de racine chez le pois de bambara [Vigna subterranea (L.)]. Les combinaisons et les concentrations dedifferents regulateurs de croissance se sont averees etre des facteurs determinants dans la frequence d'induction des cals, de meme que pour le potentiel de differenciation des cals. Les resultats montrentegalement que l'induction des cals a ete plus importante avec le petiole (75 %) sur le milieu de base MS (Murashige et Skoog, 1962) supplemente avec 3 - 5 mg/l de la N-benzylaminopurine (BAP) + 0,5 mg/l del'acide ƒ¿-naphthalene acetique (ANA). La croissance des cals (IC) a ete plus importante avec les ecotypes Ci1 (3,52) et Ci4 (2,76), tandis que la rhizogenese a ete particulierement observee chez l'ecotype Ci3(24,81 %). Pour la premiere fois, l'induction de cals organogenes et embryogenes a ete rapportee chez cette plante. Les bourgeons adventifs et les embryons somatiques ont ete inities apres 3 mois de subculture, surle milieu MS supplemente avec la BAP (3 - 5 mg/l) + ANA (0,1 - 0,5 mg/l). La frequence d'induction de l'embryogenese somatique (55 - 68 %) a ete plus elevee que celle de l'organogenese (11 - 27%)

Cryopreservation and In Vitro banking: a cool subject – Preface from the editors

Plant breeding depends largely on having access to a wide variety of plant genetic resources, which are vulnerable to losses caused by biotic and abiotic threats when grown in the field or in a greenhouse. Thus, cryopreservation or in vitro banking is a safe strategy for long-term conservation of such genetic resources, which serves as back-up collections for field genebanks and reduces. For many species, encapsulation technologies can be a promising tool for the management of plant material of high quality, the production in nurseries of plants from in vitro culture, or the conservation of plant genetic resources. Such “synthetic seeds” proved to be of great value in the medium- (slow-growth storage) and long-term (cryopreservation) conservation of germplasm of fruit, ornamental, horticultural and forestry species in small spaces. However, more research is still needed. Cryopreservation projects must have clear goals, long-term funding, skilled technical support staff, necessary infrastructure, and well-defined procedures and protocols, so that they can be routinely implemented in plant cryobanks and help to establish backup collections of valuable plant genetic resources

The bicentenary of the research on 'beautiful' vavilovia (Vavilovia formosa), a legume crop wild relative with taxonomic and agronomic potential

Vavilovia formosa is a relict, endangered species from the highlands of the Caucasus and the Near East. Described in 1812, it has had an uncertain status and was finally recognized as a separate genus of tribe Fabeae (Fabaceae). Our informal international group was established in 2007 to revive the interest in this species as it had been seriously neglected for decades. Here, we provide an overview of the accumulated knowledge on V.formosa and present the results of the most recent multidisciplinary research. Three expeditions were made to two locations in Armenia in 2009, providing the material for anatomical, morphological, chemical and molecular analysis. Unlike previous attempts, ex situ conservation in Yerevan and in vitro propagation, important for potential interspecific hybridization, were successful. Molecular tools were used to clarify the taxonomic position of V.formosa, often considered the closest to the extinct ancestor of the whole tribe. The analysis of four informative regions of plastid and nuclear DNA showed that V.formosa belongs to the same clade as Lathyrus and Pisum, with a distinct status. Preservation and maintenance of V.formosa remains the only basis for further development of all other scientific aspects, especially breeding and uses in agronomy.

Enigmatic presence of mitochondrial complex I in Trypanosoma brucei bloodstream forms

The presence of mitochondrial respiratory complex I in the pathogenic bloodstream stages of Trypanosoma brucei has been vigorously debated: increased expression of mitochondrially encoded functional complex I mRNAs is countered by low levels of enzymatic activity that show marginal inhibition by the specific inhibitor rotenone. We now show that epitope-tagged versions of multiple complex I subunits assemble into α and β subcomplexes in the bloodstream stage and that these subcomplexes require the mitochondrial genome for their assembly. Despite the presence of these large (740- and 855-kDa) multisubunit complexes, the electron transport activity of complex I is not essential under experimental conditions since null mutants of two core genes (NUBM and NUKM) showed no growth defect in vitro or in mouse infection. Furthermore, the null mutants showed no decrease in NADH:ubiquinone oxidoreductase activity, suggesting that the observed activity is not contributed by complex I. This work conclusively shows that despite the synthesis and assembly of subunit proteins, the enzymatic function of the largest respiratory complex is neither significant nor important in the bloodstream stage. This situation appears to be in striking contrast to that for the other respiratory complexes in this parasite, where physical presence in a life-cycle stage always indicates functional significance

El Pirineo Aragonés como paisaje cultural

Cultural landscapes have been constructed along centuries as a consequence of the adaptation of distinct cultures to the heterogeneity of natural systems. They are the result of a series of collective initiatives that result in the superposition of distinct elements and historical periods. In mountain environments, the most influent factors for landscape construction have been the altitudinal organization of geoecological belts, the topographic and topoclimatic diversity, the population growth, the historical events (including the cultural superposition) and the influence of local and regional markets. The success of mountain societies depended on their knowledge on the environment and of the key role of gravity to control overland flow and soil erosion. For this reason, mountain areas needed a complex social and territorial organization, to face the adversities raised by climate and strong gradients. This effort implies a big energy waste for landscape conservation, although depopulation and land abandonment can lead to landscape deconstruction. This represents the loss of a cultural inheritance that could be an excellent example of the optimum way to manage natural resources and the mistakes from the past. In spite of recent changes, many rests of Pyrenean cultural landscapes still remain: closed fields that represent an increasing individualization of landscape management, hillslopes with terraced fields, panares (terraced fields cultivated with rye) in the upper montane belt, and the extensive subalpine grasslands, which correspond to the forest wasting to favour the transhumance movements.Los paisajes culturales se han construido a lo largo de siglos o milenios como consecuencia de la adaptación de diferentes culturas a la heterogeneidad de los sistemas naturales. Son el resultado de una serie de iniciativas, generalmente colectivas, que dan lugar a la superposición de diferentes elementos que corresponden a distintos momentos históricos. En ambientes de montaña los factores más influyentes en la construcción de paisajes culturales son el escalonamiento altitudinal de los pisos geoecológicos, la diversidad topográfica y topoclimática, el crecimiento demográfico, los acontecimientos históricos (incluyendo la superposición de culturas) y la influencia de los mercados. El éxito de las sociedades montanas dependió de su conocimiento del medio y, especialmente, de la importancia de la gravedad en un ambiente de alta energía, con el fin de controlar la escorrentía y la erosión del suelo. Por eso, las áreas de montaña necesitan una organización social y territorial compleja, para hacer frente a la adversidad provocada por la rudeza del clima y la explotación de laderas pendientes. Naturalmente, este esfuerzo implica un gran gasto de energía en la conservación del paisaje, que puede desmoronarse de manera irreversible por muchas razones, entre ellas la despoblación y el abandono de tierras de cultivo, que conducen a lo que podemos llamar una deconstrucción del paisaje. Esta última representa la pérdida de un patrimonio cultural que, estudiado a fondo, nos enseña mucho acerca de la forma óptima de aprovechar los recursos naturales y también de los errores que se han cometido en el pasado. A pesar de los cambios recientes, quedan aún muchos restos de los paisajes culturales pirenaicos: campos cercados que representan una creciente individualización en la gestión del territorio, laderas aterrazadas, panares en el límite superior del piso montano, y los extensos pastos subalpinos, que representan la eliminación de un espacio forestal para favorecer los movimientos trashumantes

Beauty will save the world, but will the world save beauty? The case of highly endangered Vavilovia formosa (Stev.) Fed.

Vavilovia formosa (Stev.) Fed. is a relict, endangered species from the highlands of Caucasus and Near East. It was described in 1812, with often uncertain status and finally recognised as a separate genus of the tribe Fabeae Rchb. Our informal international group was established in 2007 to revive the interest in this species since it had been seriously neglected for decades. This review gives an overview of the accumulated knowledge on V. formosa and presents the results of its most recent multidisciplinary research. Three expeditions were made to two locations in Armenia in 2009, providing the material for anatomical, morphological, chemical and molecular analysis. Unlike previous attempts, ex situ conservation in Yerevan and in vitro propagation, important for potential interspecies hybridisation, are successful. Molecular tools were used to clarify the taxonomical position of V. formosa, often considered the closest to the extinct ancestor of the whole tribe. The analysis of four informative regions of chloroplast and nuclear DNA showed that V. formosa belonged to the same clade with Lathyrus and Pisum and with a distinct status. Preservation and maintenance of V. formosa remains the only basis for further development of all other scientific aspects, especially breeding and uses in agronomy