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We present the instrumental developments that have been performed in the framework of the ERC Synergy project Nanocosmos in the field of radio astronomy and molecular spectroscopy. Extremely sensitive radio receivers using HEMT amplifiers have been built to develop the GACELA gas cell for rotational spectroscopy in the frequency ranges 31–50 and 72–116 GHz. Similar receivers have been also installed at the Yebes 40 m radiotelescope for radioastronomical observations and molecular astrophysics studies. Several molecules have been observed with GACELA and searched for in space towards Orion, SgrB2, IRC+10216, and TMC-1. An ultradeep line survey of the cold prestellar cloud TMC-1 (QUIJOTE) has been realized with the Yebes telescope and these extremely sensitive receivers, allowing the discovery of more than 30 new molecular species, including eight cations, one anion, seven neutral S-bearing species, radicals, and a large number of hydrocarbons including the first identification of a non functionalized polycyclic aromatic hydrocarbon in space, indene (C 9 H 8 ).

338 p., Actualmente, uno de los mayores limitantes en la producción agrícola es el desarrollo de enfermedades en los cultivos, principalmente de aquellas generadas por organismos edáficos. La biodesinfección del suelo para el control de enfermedades edáficas mediante la incorporación de materia orgánica y una colchado plástico se presenta como una alternativa a la aplicación de plaguicidas sintéticos más sostenible y comprometida con la salud humana y el medio ambiente. El empleo de subproductos agroalimentarios como enmiendas orgánicas en la biodesinfección demostró efectividad contra el nematodo Meloidogyne incognita y el hongo Fusarium oxysporum f. sp. lactucae en explotaciones comerciales de lechuga afectadas. También aumentó la fertilidad del suelo y mejoró su composición microbiana favoreciendo el correcto desarrollo de los cultivos posteriores al tratamiento. Por lo tanto, el uso de estos subproductos, además de mejorar las condiciones de salud del suelo, fomenta la implantación de una economía circular en la producción agraria.

The increasing interest in agroecological practices and the current consideration of agrarian soils as a sustainable resource are driving the development of new strategies to manage soil parasites and diseases. The application of organic matter from different sources to reduce plant parasites contributes to circular economy by applying by-products as soil organic amendments that reduce wastes. Wine vinasse (WV) is a by-product generated to obtain alcohol from wine by physical methods in distilleries. The aim of this study was to determine the potential of WV and its combination with animal manure (WV+M) as soil biodisinfestation products. For this, it was compared with a plastic-covered control to distinguish the biodisinfestation from solarisation effect. The crops tested consisted of a tomato-Swiss chard rotation under glasshouse conditions. Their effects on Meloidogyne incognita, soil fertility, nematode community and crop yield were assessed. The results obtained after two seasons showed a reduction of M. incognita galling in the root system of both crops. The immediate effect after the treatment application was a reduction in the abundance of nematodes and changes in the nematode-based indices that affected all plots, including the control, most likely related to the tillage effect for the treatments application and the plastic cover. Soil fertility was improved by the application of WV (NO3−, Bioav. P) and WV+M (C, Ntotal, K), which reduced herbivore nematode metabolic footprints and enhanced bacterivore footprints. Our results indicate that the combination WV+M was effective reducing M. incognita infection, and improved crop yield. Use of by-products such as WV is a helpful tool for managing horticultural soils.

Soil food webs, which are responsible for relevant ecological functions in agroecosystems such as nutrient cycling and pest and disease suppression, represent a crucial aspect of agricultural sustainability. We studied soil properties and microfaunal food web diversity and functioning in six paired organic and conventional fields located in Central Spain to assess the effects of organic farming on soil diversity and functioning in semi-arid conditions. We hypothesized that organic farming may enhance functioning of soil food webs. Our results showed larger differences between crop types, namely olive groves and vineyards, than between farming scheme, i.e. organic and conventional fields, and few benefits of organic farming in terms of soil fertility. Soil properties (total N, C, and P, available P and K, electrical conductivity, NH4+, NO3−, soil moisture, pH) tended to present higher values in vineyards than in olive groves and in conventional than in organic fields. Some plantparasitic nematodes were associated to organic fields, especially in vineyards, and all soils fell within a degraded soil food web condition, with low Structure and Enrichment Index values. Nematode metabolic footprints showed relevant seasonal dynamics, with the more intensive herbivore activity in spring. We conclude that the lack of conventional pesticides and mineral fertilizers is probably not enough to improve soil conservation in semi-arid Mediterranean agroecosystems, and thus active soil conservation practices, as reduced tillage or cover cropping, are required to increase agroecosystem sustainability.

The epidemiology of Grapevine fanleaf virus (GFLV) and its nematode vector, Xiphinema index, was analyzed by studying the efficacy of biofumigation, fallow, and solarization as nematode control alternatives. The study was carried out in the southeastern Iberian Peninsula, at two sites in the Jumillla area (Murcia, Spain), which has a continental Mediterranean climate, a sand/loamy based soil which had been in fallow for one year and on another loam/clay/sandy soil under 10-year fallow. An absence of X. index and live grapevine roots was observed in the loam/clay/sandy soil in the 10-year fallow site X. index was not found either in the loam/sandy, biofumigated soil after one year in fallow, although there were live roots. X. index and live roots were found in soils after one year in fallow and especially in solarized soils, therefore solarization and one year in fallow are not considered effective control alternatives. It is concluded that biofumigation may be an alternative for X. index control, which can also increase soil biodiversity.

Neste traballo preséntase unha vía alternativa e totalmente orixinal de síntese de nanopartículas para a preparación de fluidos magnéticos, con mellaras respecto ós métodos tradicionais. Para elo, empréganse mezclas ternarias dun disolvente orgánico, un tensioactivo e unha disolución acuosa en forma de microemulsión, para sintetizar nanopartículas magnéticas de óxidos de ferro. Estas nanopartículas, lavadas e cubertas con ácido oleico, son estabilizadas nun líquido portador, producindo un fluido magnético. Preséntanse medidas de difracción de raios-X, microscopía electrónica de transmisión e medidas de magnetización, tanto das partículas coma do líquido preparado, In this work, an alternative and completely original route for the synthesis of magnetic fluids is presented. This method presents improvements with respect to the traditional methods. Por this purpose, ternary mixtures of organic solvent, surfactant and aqueous solution forming a microemulsion are used for the synthesis of magnetic iron oxide particles. These particles, washed and covered with oleic acid, are stabilized in a carrier liquid, producing a magnetic fluid. X-ray diffraction, transmission electron microscopy and magnetic measurements of the particles and the prepared liquid are reported