El lado humano del regadío

En este artículo se presenta la posición de UAGA-COAG respecto a los usos y la gobernanza del agua. Merece la pena su lectura pausada y profunda, ya que nos ayudará a abrir caminos de reflexión y debate en algunos aspectos donde sus argumentos mantienen algunas diferencias con otros pareceres presentados en este número de la revista

Neuropeptide growth factors and small cell lung cancer

Quiescent cultures of Swiss 3T3 cells are a useful model system for elucidating the mechanisms of mitogenesis. Here, Swiss 3T3 cells were used to test novel mitogens and characterise bombesin antagonists. Bradykinin was identified as a potent mitogen, acting in synergy with insulin. Two groups of antagonists were characterised: the substance P analogues [DArg1, DPro2, DTrp7,9, Leu11]- substance P (antagonist A), [DArg1, DPhe5, DTrp7,9, Leu11]- substance P (antagonist D) and [Arg6, DTrp7,9, Leu11] substance P(6-11) (antagonist G); and the bombesin-specific antagonists (Leu13-psi(CH2NH)Leu14]bombesin and N- acetyl-GRP(20-26). The substance P antagonists appear to interact with a common domain on the receptors for three mitogenic neuropeptides in Swiss 3T3 cells: bombesin, vasopressin and bradykinin. The bombesin-specific antagonists did not interact with other receptors. Small cell lung cancer (SCLC) is an aggressive form of lung cancer. The bombesin-like peptides, including gastrin- releasing peptide (GRP), have been postulated to act as autocrine growth factors for these tumours. In SCLC cell lines, all the antagonists were shown to block the early effect of bombesin, mobilisation of cytosolic Ca2+. The substance P antagonists also inhibited SCLC growth in liquid and semisolid media, in a reversible, dose-dependent fashion. The bombesin-specific antagonists did not inhibit SCLC growth, suggesting that other growth factors blocked by the substance P antagonists may be more important for regulating SCLC growth. A variety of peptides and hormones were tested for their ability to mobilise cytosolic Ca2+ in SCLG cell lines. Ca2+ signals were induced by GRP, vasopressin, bradykinin, cholecystokinin, galanin and neurotensin, and all were blocked by antagonists D and G. These neuropeptides are suggested as possible growth factors for SCLC

Pepper Crop under Climate Change: Grafting as an Environmental Friendly Strategy

Pepper is an extremely important vegetable worldwide in socio-economic terms. However, persistent land use, monoculture, and intensified production processes have led to soil diseases. This, along with abiotic stress, and mainly salinity of soil and waters, water stress, and suboptimal temperatures, can lead to physiological disorders emerging in peppers, e.g., cracking and Blossom end rot, which induce plant senescence, and lower not only in yields, but also in product quality. Salinity and water shortage are the two main environmental problems that crops face in the Mediterranean Region. One way of overcoming stresses from an ecological or integrated crop management viewpoint is to use grafted plants as an adaptation strategy. Initially, grafting technology has expanded in Solanaceae and Cucurbitacea species to overcome biotic stress. Nowadays, grafts are being used as several approaches to cushion the impact of climate change on agricultural systems. Furthermore, grafts allow desirable varieties by organoleptic or productivity traits, but they are sensitive to abiotic stress and can be grown under abiotic stress. As far as we know, very few studies on grafted pepper plants under abiotic stress are available

SCREENING PEPPER GENOTYPES TO OBTAIN TOLERANT ROOTSTOCKS TO SALT AND WATER STRESS: PHYSIOLOGICAL AND AGRONOMICAL RESPONSES OF THE GRAFTED PLANTS

Tesis por compendio[EN] Pepper is a vegetable of extraordinary economic and social importance in our country. Unfortunately, the persistent exploitation of the land, the monoculture and the intensification of production processes, lead to the development of soil diseases. This coupled with the abiotic stress, mainly the salinity of waters and soil, suboptimal temperatures and water stress, can induce the appearance of physiological disorders in peppers as the Blossom-end rot (BER) and cracking or cracked, induce plant senescence and decrease not only production, but also the quality of the product. Salinity and water shortages are two among the biggest environmental problems that crops have to face in the Mediterranean area. A way to overcome the stresses under the prism of an ecological or integrated crop management, is the use of grafted plants as adaptation strategy. Although there has been remarkable progress in this technique (mainly in tomato, melon, watermelon), in the cultivation of pepper use remains rare. In this Doctoral thesis several pepper genotypes have been selected through different physiological parameters which indicate tolerance to salt and water stress. Commercial cultivars were grafted onto the selected genotypes and were grown under water stress, salinity and control conditions studying several physiological, agronomic responses and the interaction rootstock/scion. The results obtained concluded that genotypes selected and used as rootstocks improved commercial varieties to salt and water stress tolerance, both in terms of performance (commercial production) compared to other commercial characters and variety without grafting. Different physiological mechanisms explain the tolerance to stress, such as the ability to maintain the water potential through an osmotic adjustment, stimulation of the antioxidant system, exclusion or retention of toxic ions (Na+ and Cl-) in saline in the roots and the maintenance of photosynthesis which allows to maintain the metabolic functions of grafted plants and production.[ES] El pimiento es una hortaliza de extraordinaria importancia económica y social en nuestro país. Lamentablemente, la persistente explotación del suelo, el monocultivo y la intensificación de los procesos de producción, conducen al desarrollo de enfermedades del suelo. Esto unido a los estreses abióticos, principalmente la salinidad de las aguas y del suelo, temperaturas subóptimas y estrés hídrico, puede inducir la aparición de fisiopatias en el pimiento como el Blossom-end rot (BER) y cracking o rajado, inducir senescencia vegetal y disminuir no solo la producción, sino también la calidad del producto. La salinidad y la escasez de agua son unos los mayores problemas medio ambientales a los que tienen que hacer frente los cultivos en el área Mediterránea. Un modo de sortear los estreses bajo el prisma de un manejo integrado o ecológico del cultivo, es la utilización de plantas injertadas como estrategia de adaptación. Aunque se ha producido un notable avance en esta técnica (principalmente en tomate, melón, sandía), en el cultivo del pimiento su utilización es poco frecuente aun. En esta Tesis Doctoral se han seleccionado mediante parámetros fisiológicos diferentes genotipos de pimiento tolerantes al estrés salino e hídrico. Los genotipos seleccionados fueron validados como patrones tolerantes a condiciones de estrés hídrico y salino injertados sobre una variedad comercial mediante el estudio de las respuestas fisiológicas, agronómicas y de la interacción patrón/variedad en ambas condiciones de estrés. De los resultados obtenidos se concluye que los genotipos seleccionados y utilizados como patrones mejoraron la tolerancia de las variedades comerciales a la salinidad, en términos de rendimiento (producción comercial) de frutos comparando con otros patrones comerciales y la variedad sin injertar. Diferentes mecanismos fisiológicos explican la tolerancia al estrés, como la capacidad de mantener el potencial hídrico mediante un ajuste osmótico, estimulación del sistema antioxidante, exclusión o retención de los iones tóxicos salinos (Na+ y Cl-) en las raíces y el mantenimiento de la fotosíntesis que permite mantener las funciones metabólicas de las plantas injertadas y la producción.[CA] El pimentó és una hortalissa d'extraordinària importància econòmica i social al nostre país. Lamentablement, la persistent explotació del sòl, el monocultiu i la intensificació dels processos de producció, conduïxen al desenrotllament de malalties del sòl. Açò unit als estressos abiòtics, principalment la salinitat de les aigües i del sòl, temperatures subòptimes i estrés hídric, pot induir l'aparició de fisiopaties en el pimentó com el Blossom-end rot (BER) i cracking, induir senescència vegetal i disminuir no sols la producció, sinó també la qualitat del producte. La salinitat i l'escassetat d'aigua són uns els majors problemes mitjà ambientals als que han de fer front els cultius en l'àrea Mediterrània. Una manera de sortejar els estressos davall el prisma d'un maneig integrat o ecològic del cultiu, és la utilització de plantes empeltades com a estratègia d'adaptació. Encara que s'ha produït un notable avanç en esta técnica (principalment en tomaca, meló, meló d'alger), en el cultiu del pimentó la seua utilització és poc freqüent. En esta Tesi Doctoral s'han seleccionat per mitjà de paràmetres fisiològics diferents genotips de pimentó tolerants a l'estrés salí i hídric. Els genotips seleccionats van ser validats com a patrons tolerants a condicions d'estrés hídric i salí empeltats sobre una varietat comercial per mitjà de l'estudi de les respostes fisiològiques, agronòmiques i de la interacció patrón/variedad en ambdós condicions d'estrés. Dels resultats obtinguts es conclou que els genotips seleccionats i utilitzats com a patrons van millorar la tolerància de les varietats comercials a la salinitat, tant en termes de rendiment (producció comercial) de fruits comparant amb altres patrons comercials i la varietat sense empeltar. Diferents mecanismes fisiològics expliquen la tolerància a l'estrés, com la capacitat de mantindre el potencial hídric per mitjà d'un ajust osmòtic, estimulació del sistema antioxidant, exclusió o retenció dels ions tòxics salins (Na+ i Cl-) en les arrels i el manteniment de la fotosíntesi que permet mantindre les funcions metabòliques de les plantes empeltades i la producció.Penella Casañ, C. (2015). SCREENING PEPPER GENOTYPES TO OBTAIN TOLERANT ROOTSTOCKS TO SALT AND WATER STRESS: PHYSIOLOGICAL AND AGRONOMICAL RESPONSES OF THE GRAFTED PLANTS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/58767TESISPremios Extraordinarios de tesis doctoralesCompendi

Treatment of gastrointestinal stromal tumor: focus on imatinib mesylate

Gastrointestinal stromal tumor (GIST) is a rare primary neoplasm of the gastrointestinal tract, mesentery, or omentum. In the past, surgery has been the only effective treatment. The diagnosis and treatment of GIST has been revolutionized over the past decade, since expression of the receptor tyrosine kinase KIT was shown to occur on these tumors. Mutations in this proto-oncogene commonly cause constitutive activation of the KIT tyrosine kinase receptor, an important factor in the pathogenesis of the disease. The development of specific tyrosine kinase inhibitors, such as imatinib mesylate, has led to a breakthrough in the treatment of advanced GIST. Treatment with this drug has led to significant improvements in survival, with overall response rates in excess of 80%. Side effects are common, but usually manageable. The success of this drug has led to further trials investigating its use in the pre- and postoperative situation. This review summarizes the current knowledge of GIST and imatinib treatment and possible future developments

Consciousness in Thinks... by David Lodge

El estudio de la conciencia ha sido objeto de debate durante siglos, especialmente en el campo de la filosofía. Sin embargo, el análisis de esta en el campo de la literatura es bastante reciente y por lo tanto, novedoso, puesto que su origen se remonta al siglo XIX. Dicho interés por el estudio de la conciencia en la literatura radica en la posibilidad de acceder a los pensamientos de otra persona, lo cual no es posible en la vida real. Así pues, el presente trabajo consiste en un análisis del concepto de la conciencia a través de la novela Thinks… del autor británico David Lodge.´ El trabajo comienza con una introducción en la que se define el concepto de la conciencia así como el contexto, su origen y sus aplicaciones, tanto en el ámbito de la psicología y la filosofía como en la literatura. A continuación, analiza a fondo el concepto de la conciencia temática y formalmente centrándose en la novela Thinks…. Por último, se estudian las técnicas narrativas utilizadas para la representación de la conciencia en la novela analizada. El trabajo concluye con la premisa de que es imposible acceder a la conciencia y los pensamientos de otra persona en la vida real, a menos que sea, por ejemplo, en una obra de literatura como es el caso de la novela analizada, Thinks…

Himerius and the Praetorian Prefect Secundus Salutius

Himerius’ oration 42 Colonna, devoted to Julian’s old friend, was read in his presence or was sent to him, before Himerius’ return to Athens

A review of commercial energy harvesters for autonomous sensors

Current commercial autonomous sensors are mainly powered by primary batteries. Batteries need to be replaced and hence can become the largest and most expensive part of the system. On the other hand, our environment is full of waste and unused energy such as that coming from the sun or mechanical vibrations. As a result, commercial energy harvesters are increasingly available to power autonomous sensors. This work presents and analyses commercial energy harvesters currently available. First, environmental energy sources are classified and described. Then, energy harvesting principles are described and some guidelines are given to calculate the maximum power consumption allowed and the energy storage capacity required for the autonomous sensor. Finally, commercial energy harvesters are evaluated to determine their capability to power a commercial autonomous sensor in some given circumstances

Chlorophyll fluorescence imaging can reflect development of vascular connection in grafting union in some Solanaceae species

[EN] Graft union development in plants has been studied mainly by destructive methods such as histological studies. The aim of this work was to evaluate whether the chlorophyll fluorescence imaging (CFI) technique is sensitive enough to reflect changes at the cellular level in different Solanaceae grafted plants 30 d after grafting, when both grafted partners were well fused and strong enough in all plant combinations. The pepper cultivar 'Adige' was grafted onto different Capsicum spp. accessions typified with different compatibility degrees; eggplant was grafted on Solanum torvum and pepper homografts as compatible unions; pepper was grafted on S. torvum and on tomato as incompatible unions. 'Adige'/'Adige' and 'Adige'/pepper A25 showed a higher maximum quantum efficiency of PSII associated with higher values of actual quantum efficiency of PSII and photochemical quenching as well as with vascular regeneration across the graft interface. Our results highlighted that CFI changes reflected histological observations in grafted Solanaceae plants.This work was financed by INIA (Spain) through Project RTA2013-00022-C02-01 and the European Regional Development Fund (ERDF).Penella-Casañ, C.; Pina, A.; San Bautista Primo, A.; López Galarza, SV.; Calatayud, A. (2017). Chlorophyll fluorescence imaging can reflect development of vascular connection in grafting union in some Solanaceae species. Photosynthetica. 55(4):671-678. https://doi.org/10.1007/s11099-017-0690-7S671678554Berger, S., Benediktyová, Z., Matouš, K., Bonfig, K., Mueller, M. J., Nedbal, L., & Roitsch, T. (2006). Visualization of dynamics of plant–pathogen interaction by novel combination of chlorophyll fluorescence imaging and statistical analysis: differential effects of virulent and avirulent strains of P. syringae and of oxylipins on A. thaliana. Journal of Experimental Botany, 58(4), 797-806. doi:10.1093/jxb/erl208Bilger, W., & Björkman, O. (1991). Temperature dependence of violaxanthin de-epoxidation and non-photochemical fluorescence quenching in intact leaves of Gossypium hirsutum L. and Malva parviflora L. Planta, 184(2), 226-234. doi:10.1007/bf00197951Calatayud, Á., Gorbe, E., Roca, D., & Martínez, P. F. (2008). Effect of two nutrient solution temperatures on nitrate uptake, nitrate reductase activity, NH4+ concentration and chlorophyll a fluorescence in rose plants. Environmental and Experimental Botany, 64(1), 65-74. doi:10.1016/j.envexpbot.2008.02.003Clearwater, M. J., Lowe, R. G., Hofstee, B. J., Barclay, C., Mandemaker, A. J., & Blattmann, P. (2004). Hydraulic conductance and rootstock effects in grafted vines of kiwifruit. Journal of Experimental Botany, 55(401), 1371-1382. doi:10.1093/jxb/erh137DELOIRE, A., & HÉBANT, C. (1982). Peroxidase Activity and Lignification at the Interface Between Stock and Scion of Compatible and Incompatible Grafts of Capsicum on Lycopersicum. Annals of Botany, 49(6), 887-891. doi:10.1093/oxfordjournals.aob.a086314Dhondt, S., Vanhaeren, H., Van Loo, D., Cnudde, V., & Inzé, D. (2010). Plant structure visualization by high-resolution X-ray computed tomography. Trends in Plant Science, 15(8), 419-422. doi:10.1016/j.tplants.2010.05.002Errea, P., Garay, L., & Marín, J. A. (2001). Early detection of graft incompatibility in apricot (Prunus armeniaca ) using in vitro techniques. Physiologia Plantarum, 112(1), 135-141. doi:10.1034/j.1399-3054.2001.1120118.xErrea, P. (1998). Implications of phenolic compounds in graft incompatibility in fruit tree species. Scientia Horticulturae, 74(3), 195-205. doi:10.1016/s0304-4238(98)00087-9Errea, P., Felipe, A., & Herrero, M. (1994). Graft establishment between compatible and incompatiblePrunusspp. Journal of Experimental Botany, 45(3), 393-401. doi:10.1093/jxb/45.3.393FERNANDEZ-GARCIA, N. (2004). Graft Union Formation in Tomato Plants: Peroxidase and Catalase Involvement. Annals of Botany, 93(1), 53-60. doi:10.1093/aob/mch014Fernández-García, N., Martínez, V., & Carvajal, M. (2004). Effect of salinity on growth, mineral composition, and water relations of grafted tomato plants. Journal of Plant Nutrition and Soil Science, 167(5), 616-622. doi:10.1002/jpln.200420416Flaishman, M. A., Loginovsky, K., Golobowich, S., & Lev-Yadun, S. (2008). Arabidopsis thaliana as a Model System for Graft Union Development in Homografts and Heterografts. Journal of Plant Growth Regulation, 27(3), 231-239. doi:10.1007/s00344-008-9050-yGenty, B., Briantais, J.-M., & Baker, N. R. (1989). The relationship between the quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescence. Biochimica et Biophysica Acta (BBA) - General Subjects, 990(1), 87-92. doi:10.1016/s0304-4165(89)80016-9Goldschmidt, E. E. (2014). Plant grafting: new mechanisms, evolutionary implications. Frontiers in Plant Science, 5. doi:10.3389/fpls.2014.00727Guidi, L., Mori, S., Degl’Innocenti, E., & Pecchia, S. (2007). Effects of ozone exposure or fungal pathogen on white lupin leaves as determined by imaging of chlorophyll a fluorescence. Plant Physiology and Biochemistry, 45(10-11), 851-857. doi:10.1016/j.plaphy.2007.07.001Hudina, M., Orazem, P., Jakopic, J., & Stampar, F. (2014). The phenolic content and its involvement in the graft incompatibility process of various pear rootstocks (Pyrus communis L.). Journal of Plant Physiology, 171(5), 76-84. doi:10.1016/j.jplph.2013.10.022Irisarri, P., Binczycki, P., Errea, P., Martens, H. J., & Pina, A. (2015). Oxidative stress associated with rootstock–scion interactions in pear/quince combinations during early stages of graft development. Journal of Plant Physiology, 176, 25-35. doi:10.1016/j.jplph.2014.10.015Kawaguchi, M., Taji, A., Backhouse, D., & Oda, M. (2008). Anatomy and physiology of graft incompatibility in solanaceous plants. The Journal of Horticultural Science and Biotechnology, 83(5), 581-588. doi:10.1080/14620316.2008.11512427Mudge, K., Janick, J., Scofield, S., & Goldschmidt, E. E. (2009). A History of Grafting. Horticultural Reviews, 437-493. doi:10.1002/9780470593776.ch9�quist, G., & Chow, W. S. (1992). On the relationship between the quantum yield of Photosystem II electron transport, as determined by chlorophyll fluorescence and the quantum yield of CO2-dependent O2 evolution. Photosynthesis Research, 33(1), 51-62. doi:10.1007/bf00032982OXBOROUGH, K., & BAKER, N. R. (1997). An instrument capable of imaging chlorophyll a fluorescence from intact leaves at very low irradiance and at cellular and subcellular levels of organization. Plant, Cell and Environment, 20(12), 1473-1483. doi:10.1046/j.1365-3040.1997.d01-42.xPadgett, M., & Morrison, J. C. (1990). Changes in Grape Berry Exudates during Fruit Development and Their Effect on Mycelial Growth of Botrytis cinerea. 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Graft union formation and cell-to-cell communication via plasmodesmata in compatible and incompatible stem unions of Prunus spp. Scientia Horticulturae, 143, 144-150. doi:10.1016/j.scienta.2012.06.017Pina, A., Errea, P., Schulz, A., & Martens, H. J. (2009). Cell-to-cell transport through plasmodesmata in tree callus cultures. Tree Physiology, 29(6), 809-818. doi:10.1093/treephys/tpp025Quilliam, R. S., Swarbrick, P. J., Scholes, J. D., & Rolfe, S. A. (2005). Imaging photosynthesis in wounded leaves of Arabidopsis thaliana. Journal of Experimental Botany, 57(1), 55-69. doi:10.1093/jxb/erj039Rolfe, S. A., & Scholes, J. D. (2010). Chlorophyll fluorescence imaging of plant–pathogen interactions. Protoplasma, 247(3-4), 163-175. doi:10.1007/s00709-010-0203-zRouphael, Y., Schwarz, D., Krumbein, A., & Colla, G. (2010). Impact of grafting on product quality of fruit vegetables. Scientia Horticulturae, 127(2), 172-179. doi:10.1016/j.scienta.2010.09.001Sánchez-Rodríguez, E., Romero, L., & Ruiz, J. M. (2013). Role of Grafting in Resistance to Water Stress in Tomato Plants: Ammonia Production and Assimilation. Journal of Plant Growth Regulation, 32(4), 831-842. doi:10.1007/s00344-013-9348-2Savvas, D., Colla, G., Rouphael, Y., & Schwarz, D. (2010). Amelioration of heavy metal and nutrient stress in fruit vegetables by grafting. Scientia Horticulturae, 127(2), 156-161. doi:10.1016/j.scienta.2010.09.011Schöning, U., & Kollmann, R. (1997). Phloem translocation in regeneratingin vitro- heterografts of different compatibility. Journal of Experimental Botany, 48(2), 289-295. doi:10.1093/jxb/48.2.289Schreiber, U., Schliwa, U., & Bilger, W. (1986). Continuous recording of photochemical and non-photochemical chlorophyll fluorescence quenching with a new type of modulation fluorometer. Photosynthesis Research, 10(1-2), 51-62. doi:10.1007/bf00024185Tadeo, F. 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Application of modulated chlorophyll fluorescence and modulated chlorophyll fluorescence imaging to study the environmental stress effect

Chlorophyll (Chl) a fluorescence is a widely used tool to monitor the photosynthetic process in plants subjected to environmental stresses. this review reports the theoretical bases of Chl fluorescence, and the significance of the most important Chl fluorescence parameters. it also reports how these parameters can be utilised to estimate changes in photosystem (Ps) ii photochemistry, linear electron flux and dissipation mechanisms. the relation between actual Psii photochemistry and Co2 assimilation is discussed, as is the role of photochemical and non-photochemical quenching in inducing changes in Psii activity. the application of Chl fluorescence imaging to study heterogeneity on leaf lamina is also considered. this review summarises only some of the results obtained by this methodology to study the effects of different environmental stresses, namely water availability, nutrients, pollutants, temperature and salinity