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Locally-adapted Italian cultivars of tomato (Solanum lycopersicum L.) under drought stress: morpho-physiological, biochemical and nutraceutical aspects underlying stress tolerance
Full text linkBackground: Water deficit is one of the 21st century's major challenges, agriculture being both the cause and the victim since 70% of global available water is used for its practices. Irrigation is fundamental but, as climate change becomes more persistent, there is a need to conserve water and use it more efficiently. Exposure of plants to drought stress can cause morphological, anatomical, physiological, and biochemical changes in many tissues and organs. Drought can affect the growth and development of plant organs causing drastic reduction in productivity and commercial performance. It is therefore crucial to identify cultivars that can tolerate drought. When dealing with economically relevant crops like tomatoes, this purpose is even more incisive and local agrobiodiversity is a large genetic reservoir of promising cultivars.
Aims and Methods: Nine local Italian and four commercial tomato cultivars were considered. All experienced approximately 20 days of drought during the vegetative and reproductive phases. Plants were studied for three aspects. Morpho-physiology: several physio-morphological parameters were monitored, such as stomatal conductance, photosynthesis, water use efficiency, growth, and soil water content. The different responses and behaviors allowed the cultivars to be divided into three groups: tolerant, susceptible, and intermediate. The classification was also confirmed by the principal component analysis. Biochemistry: the expression of proteins related to drought stress tolerance in four local tomato cultivars was evaluated. Cultivars were selected after the results of previous analyses and corresponded to different tolerance levels. Only the vegetative stage was considered in this section. The approach consisted of extraction, separation, and immunological analysis of proteins such as dehydrins, osmotin, HSP70s, sucrose synthase, and cyclophilin. We also analyzed the pattern of phosphorylated proteins and the isoforms of RuBisCO. Nutraceutics: Genetic factors, ripeness and the impact of environmental conditions lead to differences in the bio-metabolic and nutraceutical composition of tomato fruit. We tested the hypothesis that local tomato cultivars subjected to drought stress showed an increased capacity for biosynthesis of compounds with antioxidant activity. The antioxidant power and the total content of polyphenols and flavonoids in both pulp and peel were evaluated by colorimetric assays. In addition, flavonoids (such as rutin, naringenin, and caffeic acid), vitamin C, and lycopene were identified and quantified using HPLC methods.
Results and Conclusions: At last, the data obtained at the morphological, physiological, biochemical, and metabolic levels indicate that specific locally adapted tomato cultivars respond much more efficiently to drought stress, even more than widespread commercial cultivars. In addition, this study lays the foundations for an application aspect, namely the use of moderate and controlled drought stress conditions to increase the nutritional quality of tomato fruits. Given that many bioactive compounds are found in the peel of tomatoes, this supports the reuse of waste components and therefore their sustainable recovery
Let's shape again: the concerted molecular action that builds the pollen tube
No full textKey message: The pollen tube is being subjected to control by a complex network of communication that regulates its shape and the misfunction of a single component causes specific deformations. In flowering plants, the pollen tube is a tubular extension of the pollen grain required for successful sexual reproduction. Indeed, maintaining the unique shape of the pollen tube is essential for the pollen tube to approach the embryo sac. Many processes and molecules (such as GTPase activity, phosphoinositides, Ca2+ gradient, distribution of reactive oxygen species and nitric oxide, nonuniform pH values, organization of the cytoskeleton, balance between exocytosis and endocytosis, and cell wall structure) play key and coordinated roles in maintaining the cylindrical shape of pollen tubes. In addition, the above factors must also interact with each other so that the cell shape is maintained while the pollen tube follows chemical signals in the pistil that guide it to the embryo sac. Any intrinsic changes (such as erroneous signals) or extrinsic changes (such as environmental stresses) can affect the above factors and thus fertilization by altering the tube morphology. In this review, the processes and molecules that enable the development and maintenance of the unique shape of pollen tubes in angiosperms are presented emphasizing their interaction with specific tube shape. Thus, the purpose of the review is to investigate whether specific deformations in pollen tubes can help us to better understand the mechanism underlying pollen tube shape
Cebada Cervecera: comportamiento agronómico y de calidad en Oliveros (Santa Fe). Campaña 2019
Full text linkLa cebada cervecera es un cultivo de suma importancia en la industria de la maltería. Al igual que el trigo, es una gramínea que aporta a la sustentabilidad de los sistemas de producción por el gran volumen de biomasa que genera; en comparación con el trigo, tolera mejor la sequía y su cosecha es más anticipada a este cereal.EEA OliverosFil: Manlla, Amalia Graciela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Oliveros; ArgentinaFil: Conti, Veronica Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bordenave; ArgentinaFil: Moreyra, Federico. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bordenave; Argentin
Calidad industrial de la cebada cervecera: impacto de la fecha de siembra
Full text linkEntre otras importantes decisiones de manejo que afectan el rendimiento del cultivo de cebada, la elección de la fecha de siembra tiene un impacto decisivo sobre la calidad comercial e industrial del grano, que atañen a la cadena de la cebada y la malta con destino a la elaboración de cerveza.EEA BordenaveFil: Gil, Antonela. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Miravalles, Marta. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Moreyra, Federico. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bordenave; ArgentinaFil: Conti, Veronica Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bordenave; Argentin
Functional roles of osmotin, dehydrin and aquaporin in drought stress response: comparative analysis in tomato and olive
No full textClimate change is exacerbating the frequency and severity of droughts, thereby inducing
substantial stress in crops. This review investigates the molecular responses to water deficit in two key Mediterranean crops: the annual tomato (Solanum lycopersicum) and the perennial olive (Olea europaea). The focus is on the function of osmotin, dehydrin (DHN) and aquaporin (AQP) proteins, which are essential for drought stress tolerance. Osmotin protects enzymes and functions as a chaperone, DHNs mitigate oxidative stress and enhance water retention, and AQPs control water transport. A comparative analysis of tomato and olive demonstrates contrasting adaptive mechanisms. Tomato, an annual plant, increases AQP expression to promote photosynthesis, despite increased water loss, and quickly completes its life cycle. Olive, a perennial species, exhibits a more complex AQP modulation, decreasing expression during stress and increasing it during recovery for water conservation. Olive trees also accumulate DHNs as a defense against dehydration. These molecular differences in osmotin, DHN and AQP responses highlight the distinct adaptive strategies of annual and perennial species. This review offers insights into drought tolerance mechanisms in crops, potentially aiding the development of climate-resilient varieties
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Effects of Drying Methods and Temperatures on the Quality of Chestnut Flours
Full text linkThe demand for chestnut flour is growing because of its use in gluten-free products. Previous studies have correlated the quality of chestnut flours to the drying temperature and technology applied. This work is a novel study on the role of the traditional drying method with a wood fire in a “metato” building for flour compared with a food dryer at 40 °C or 70 °C. The contents of antioxidants, total polyphenols and sugars were determined as well as the presence of toxic volatiles or aflatoxins. The flour, resulting from the traditional method, presented lower polyphenol content and antioxidant power compared to the others. The content of the sugars was similar to the flours obtained after drying with hot air, both at 40 °C and 70 °C. The toxic volatile molecules, furfural, guaiacol, and o-cresol, were found. There was no correlation between the aflatoxin content and the presence of damage in chestnut fruits. The traditional method should not be abandoned since it confers a pleasant smoky taste to the product, but it is necessary to regulate the level and steadiness of temperature. Future research needs to be directed to the quantification of harmful volatile compounds and their correlation with the quantity of smoke emitted by the wood fire
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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