Nematicidal activity of essential oils and organic amendments from Asteraceae against root-knot nematodes

The essential oil of Chrysanthemum coronarium flowerheads showed strong nematicidal activity in vitro and in growthchamber experiments. Essential oil concentrations of 2, 4, 8 and 16 μL mL−1, significantly reduced hatch, J2 survival (determined by final value and area under curves of cumulative percentage hatch or mortality) and reproduction rate of Meloidogyne artiellia in vitro, with the lowest values occurring at 16 μL mL−1. In pot trials with chickpea cv. PV 61, essential oil concentrations of 10–40 μL per 500 cm3 soil, applied on sterile cotton pellets, also significantly reduced the nematode’s reproduction rate. The biological processes of mortality and hatching/reproduction were adequately described by the monomolecular and expanded negative exponential models, respectively. Effectiveness of soil amendment with either flowers, leaves, roots or seeds of C. coronarium, and flowers from several species of Asteraceae (Chrysanthemum segetum, Calendula maritima, Calendula officinalis and Calendula suffruticosa) at 5 g per 500 cm3 soil was tested for suppression of M. artiellia and growth of chickpea cv. PV 61 under growth-chamber conditions. In these tests, flowers of all five Asteraceae species and various parts of C. coronarium significantly reduced reproduction rates of M. artiellia, by 83·0–95·9%, with the minimum rates occurring in infected chickpea plants amended with flowers of C. officinalis and C. suffruticosa. The in vitro and in planta results suggest that the essential oil of C. coronarium and organic amendments from Asteraceae species may serve as nematicides.This research, part of a PhD study by P.P., was supported by grant SC98-022 and a fellowship from the Instituto Nacional de Tecnologías Agroalimentarias (INIA).Peer reviewe

ICAR: endoscopic skull‐base surgery

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From Computer Metaphor to Computational Modeling: The Evolution of Computationalism

In this paper, I argue that computationalism is a progressive research tradition. Its metaphysical assumptions are that nervous systems are computational, and that information processing is necessary for cognition to occur. First, the primary reasons why information processing should explain cognition are reviewed. Then I argue that early formulations of these reasons are outdated. However, by relying on the mechanistic account of physical computation, they can be recast in a compelling way. Next, I contrast two computational models of working memory to show how modeling has progressed over the years. The methodological assumptions of new modeling work are best understood in the mechanistic framework, which is evidenced by the way in which models are empirically validated. Moreover, the methodological and theoretical progress in computational neuroscience vindicates the new mechanistic approach to explanation, which, at the same time, justifies the best practices of computational modeling. Overall, computational modeling is deservedly successful in cognitive (neuro)science. Its successes are related to deep conceptual connections between cognition and computation. Computationalism is not only here to stay, it becomes stronger every year

Efectos del aceite esencial de inflorescencias de "Chrysanthemun coronarium" L. en mosca blanca y plagas de almacén

La destilación al vapor de inflorescencias de la compuesta Chrysanthemum coronarium L. da lugar a un aceite esencial azul desagradablemente oloroso. En una serie de ensayos de laboratorio se estudiaron sus efectos antiinsectos utilizando la mosca blanca Bemisia tabaci (Homoptera: Aleyrodidae) y las plagas de almacén Tribolium castaneum (Coleoptera: Tenebrionidae), Acanthoscelides obtectus (Coleoptera: Bruchidae) y Ephestia kuehniella (Lepidoptera: Pyralidae). La aplicación tópica a larvas, de plagas de almacén, produjo una alta mortalidad, siendo la DL50 a las 24 h de 0,045 myl / larva para T. castaneum. Además del efecto insecticida también se observó un rápido efecto de choque inmediato a la aplicación (DC50 = 0,029 myl / larva para T. castaneum). Los adultos de A. obtectus fueron más sensibles a los vapores del aceite esencial (1 myl / placa) que los de T. castaneum (5 myl / placa), si bien la mariposa E. kuehniella fue la más susceptible al efecto insecticida, disminuyendo su fecundidad al inhalar vapores del aceite esencial. Los efectos en mosca blanca no son claros, pero sugieren repelencia y toxicidad volátil al acondicionar previamente el material vegetal con el aceite esencial. Se discuten los efectos obtenidos en los experimentos y sus implicaciones para la utilización de este producto natural en el control de plagas

Germination studies of castorbean seeds from a Spanish germplasm collection

Trabajo presentado en la International Conference on "Industrial Crops and Products" (includes: 26th Annual Meeting of the Association for the Advancement of Industrial Crops and FIBRA and OPTIMA Workshops), celebrada en Atenas del 13 al 19 de xeptiembre de 2014.N

Distribución espacial del pulgón Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) en un cultivo intercalado de lechuga ecológica

La lechuga es uno de los principales cultivos hortícolas de la Región de Murcia. Se ha realizado una plantación tardía (6 de marzo de 2003) de lechuga ecológica en el Campo de Cartagena, con objeto de estudiar el efecto de borde de plantas en plena floración de crisantemo (Chrysanthemum coronarium) y coriandro (Coriandrum sativum) en la población de pulgón y sus enemigos naturales. Se realizaron conteos semanales de pulgones y sus depredadores en 180 lechugas. Los primeros alados de Nasonovia ribisnigri (Mosley) se observaron el 14 de marzo. Se produjo un incremento de las colonias ápteras que alcanzó su máximo el 23 de abril. A partir de esta fecha aparecieron larvas de sírfidos que depredaron activamente los pulgones. La infestación afectó al 80-100% de lechugas, si bien a partir del acogollado y con la aparición de los sírfidos se produjo una disminución progresiva hasta alcanzar el 30-40% de lechugas infestadas en el momento de la recolección. Se ha realizado el análisis de la distribución espacial temporal del pulgón y las larvas de sírfidos en la parcela de cultivo

Variability of seed quality traits in wild and semi-wild accessions of castor collected in Spain

The Mediterranean Basin is an important center of diversity for castor (Ricinus communis L.). We conducted seed collections from 121 wild and semi-wild (feral) populations growing in southern and eastern provinces of Spain. The objective of this research was to evaluate seed weight, oil content, fatty acid profile, and tocopherol and phytosterol contents and profiles in this germplasm collection at different environments. The seeds collected in the source locations as well as those produced in seed increases conducted in Córdoba (southern Spain) and Murcia (southeastern Spain) were analyzed. Analysis of variance considering three locations (source location, Córdoba, Murcia) and the genotypes was conducted. The contribution of genotype to total variation was particularly high for hundred-seed weight (89.8% of total sums of squares) and concentrations of Δ5-avenasterol (85.4%) and β-sitosterol (79.2%). Large variability was identified for most of the traits. The ranges of variation, averaged from data of at least two environments, were 11.6–59.1 g for hundred-seed weight, 44.6–54.8% for oil content, 99.6–282.0 mg kg−1 seed kernel for tocopherol content, 27.4–50.5% for the concentration of δ-tocopherol, 1090–2865 mg kg−1 seed for phytosterol content, and 15.1–54.1% for the concentration of Δ5-avenasterol. Little variation was found for fatty acid profile. One accession (ALM-2011-37) showed exceptionally high phytosterol content and three accessions from the same locality (CAD-2010-26 through 28) had high levels of Δ5-avenasterol. The results emphasized the potential of wild and semi-wild germplasm for improving seed and oil quality in castor.This research was undertaken under the project INIA RF2010-00002-C02 partly funded with the FEDER programme.Peer reviewe

Building a castor (Ricinus communis L., Euphorbiaceae) germplasm collection in Spain

Contribution for the 25th Anniversary Meeting of the Association for Advancement of Industrial Crops (AAIC): New Crops: Bioenergy, Biomaterials, and Sustainability, held in Washington D.C, October 13-16, 2013. More details at http://www.aaic.org/2013_meeting.htmCastor plant (Ricinus communis L.) is a member of the spurge family and a minor non-food oilseed crop at the world scale, and this plant has great potential as a raw material for biorefineries. Over 95% of the castor oil production is based in India. china, mozambique, and Brazil, but there is potential to grow R. communis in semiarid temperature regions.Peer reviewe