Summary In this study, growth‐dependent changes in the mechanical properties of the tomato (Solanum lycopersicum) cuticle during fruit development were investigated in two cultivars with different patterns of cuticle growth and accumulation. The mechanical properties were determined in uniaxial tensile tests using strips of isolated cuticles. Changes in the functional groups of the cuticle chemical components were analysed by attenuated total reflectance–Fourier transform infrared (ATR‐FTIR). The early stages of fruit growth are characterized by an elastic cuticle, and viscoelastic behaviour only appeared at the beginning of cell enlargement. Changes in the cutin:polysaccharide ratio during development affected the strength required to achieve viscoelastic deformation. The increase in stiffness and decrease in extensibility during ripening, related to flavonoid accumulation, were accompanied by an increase in cutin depolymerization as a result of a reduction in the overall number of ester bonds. Quantitative changes in cuticle components influence the elastic/viscoelastic behaviour of the cuticle. The cutin:polysaccharide ratio modulates the stress required to permanently deform the cuticle and allow cell enlargement. Flavonoids stiffen the elastic phase and reduce permanent viscoelastic deformation. Ripening is accompanied by a chemical cleavage of cutin ester bonds. An infrared (IR) band related to phenolic accumulation can be used to monitor changes in the cutin esterification index.

Flavonoids accumulate in tomato (Solanum lycopersicum L.) fruit cuticles during ripening. Their quantitative contribution to the biomechanical properties of the cuticle is studied in six tomato genotypes which show presence or absence of these compounds at the red ripe stage of fruit development. Tomato cuticles with flavonoids at red ripe showed a dramatic increase of these compounds between mature green and red ripe stages together with a significant increase in the elastic modulus. On the other hand, cuticles without flavonoids displayed a similar biomechanical behaviour at mature green and red ripe stages. The absence of flavonoids could also be related with a predominance of the viscoelastic performance of the cuticle. Thus, the increase of phenolics in tomato fruit cuticles during ripening is correlated with a more rigid cutin network that reinforces the mechanical function of polysaccharides which tend to diminish at this stage due to cell wall disassembly. A role of phenolics as biomechanical modulators of the cuticle behaviour is proposed.

Tomato (Solanum lycopersicum) fruit ripening is accompanied by an increase in CHALCONE SYNTHASE (CHS) activity and flavonoid biosynthesis. Flavonoids accumulate in the cuticle, giving its characteristic orange color that contributes to the eventual red color of the ripe fruit. Using virus-induced gene silencing in fruits, we have down-regulated the expression of SlCHS during ripening and compared the cuticles derived from silenced and nonsilenced regions. Silenced regions showed a pink color due to the lack of flavonoids incorporated to the cuticle. This change in color was accompanied by several other changes in the cuticle and epidermis. The epidermal cells displayed a decreased tangential cell width; a decrease in the amount of cuticle and its main components, cutin and polysaccharides, was also observed. Flavonoids dramatically altered the cuticle biomechanical properties by stiffening the elastic and viscoelastic phase and by reducing the ability of the cuticle to deform. There seemed to be a negative relation between SlCHS expression and wax accumulation during ripening that could be related to the decreased cuticle permeability to water observed in the regions silencing SlCHS. A reduction in the overall number of ester linkages present in the cutin matrix was also dependent on the presence of flavonoids.

Fruit cuticle composition and their mechanical performance have a special role during ripening because internal pressure is no longer sustained by the degraded cell walls of the pericarp but is directly transmitted to epidermis and cuticle which could eventually crack. We have studied fruit growth, cuticle modifications and its biomechanics, and fruit cracking in tomato; tomato has been considered a model system for studying fleshy fruit growth and ripening. Tomato fruit cracking is a major disorder that causes severe economic losses and, in cherry tomato, crack appearance is limited to the ripening process. As environmental conditions play a crucial role in fruit growing, ripening and cracking, we grow two cherry tomato cultivars in four conditions of radiation and relative humidity (RH). High RH and low radiation decreased the amount of cuticle and cuticle components accumulated. No effect of RH in cuticle biomechanics was detected. However, cracked fruits had a significantly less deformable (lower maximum strain) cuticle than non-cracked fruits. A significant and continuous fruit growth from mature green to overripe has been detected with special displacement sensors. This growth rate varied among genotypes, with cracking-sensitive genotypes showing higher growth rates than cracking-resistant ones. Environmental conditions modified this growth rate during ripening, with higher growing rates under high RH and radiation. These conditions corresponded to those that favored fruit cracking. Fruit growth rate during ripening, probably sustained by an internal turgor pressure, is a key parameter in fruit cracking, because fruits that ripened detached from the vine did not crack.

La inmigración venezolana ha sido representada en múltiples medios de comunicación y  en ellos se refleja la crisis humanitaria dentro del país y de aquellos que han decidido salir de él. La Opinión en su cibermedio www.laopinion.com.co ha dado una cobertura periodística  constante al ser un medio representativo de la región fronteriza del Departamento Norte de Santander, en Colombia y el estado Táchira en Venezuela. Por ello, esta investigación propone como objetivo general describir el tratamiento periodístico dado a la información sobre el inmigrante venezolano en el cibermedio colombiano La Opinión, mediante un análisis de contenido a la sección Frontera. Entre los resultados destacan: febrero es el mes con mayor frecuencia, las unidades informativas carecen de antetítulo, dominan los títulos informativos y las noticias, gobierno es la fuente más consultada, el tema con más aparición es Sociedad, la etiqueta más empleada es Venezuela, hay uso de hipervínculos internos y existe interactividad. Se concluye que es necesario consultar otras fuentes para darle cobertura al tema, generar otros géneros periodísticos que permitan dar profundidad a la temática y manejar un lenguaje  que no atente contra el inmigrante.

New technologies allow the use of applicable tools in different areas of knowledge adapted to the educational needs of the subject (Domingo, et al., 2011)

Tomando como base el Atlas Florae Europeae se ha realizado una revisión corológica de la pteridoflora ibérica y balear.