Salinity effect on nutritional value, chemical composition and bioactive compounds content of Cichorium spinosum L.

Soil salinization is an increasing problem for many areas throughout the world that renders prohibitive vegetables and crop production in general. In the present study, Cichorium spinosum L. plants were grown under saline conditions in order to evaluate chemical composition and bioactive compounds content of their leaves. Salinity increase resulted in significant changes of macro and micro-nutrients content (nutritional value, sugars, fatty acids, minerals, ascorbic acid and tocopherols), whereas the concentration of phenolic compounds was not significantly affected. Chicoric and 5-O-caffeoylquinic acid were the most abundant phenolic acids. In contrast, antioxidant activity and mineral composition were beneficially affected by mid-to-high and high salinity levels. In conclusion, C. spinosum can be cultivated under saline conditions without compromising the quality of the final product, especially in semi-arid areas where irrigation water is scarce and/or of low quality due to high content of NaCl (coastal areas or areas where underground water is saline).info:eu-repo/semantics/publishedVersio

Evaluation of various ecotypes of “stamnagathi’ (Cichorium spinosum L.)

In the present study, the evaluation of chemical composition of various ecotypes of “stamnagathi” (Cichorium spinosum L.) was carried out. Seeds from selected ecotypes were collected in situ and sown in seed trays for plant propagation and consequent plant production. At the harvest stage, the dry matter, chlorophyll, sugars, fatty acids and organic acids content in leaves was measured. Regarding dry matter content, significant differences were observed among the ecotypes, with mean values ranging from 6.3 to 8.3%. Differences were also observed in chlorophyll a, b and total chlorophyll, with ecotypes B and D having the highest content comparing to ecotypes A and C. Sugars content differed among the ecotypes for all the detected sugars (glucose, fructose, sucrose) and the total sugars content. Ascorbic acid was detected only in the case of ecotypes B and C, whereas in the other two ecotypes only traces were detected. Finally, regarding tocopherols content, significant differences were observed for both α- tocopherol, with ecotype B having the highest content followed by ecotype C, and δ- tocopherol, where the highest content was observed for ecotype C. For total tocopherols, ecotype C had also the highest content comparing to the other ecotypes. Fatty acids content did not differ among the studied ecotypes, for both the content of the main fatty acids (α-linolenic, linoleic and palmitic acid) and the monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and total fatty acids (TFA) content. In conclusion, genotype has an important effect on nutritional and chemical composition of ‘stamnagathi’ ecotypes, and special interest rises for detecting and evaluating ecotypes with high quality profile for commercial cultivation.info:eu-repo/semantics/publishedVersio

Evaluation of various ecotypes of “stamnagathi’ (Cichorium spinosum L.)

In the present study, the evaluation of chemical composition of various ecotypes of “stamnagathi” (Cichorium spinosum L.) was carried out. Seeds from selected ecotypes were collected in situ and sown in seed trays for plant propagation and consequent plant production. At the harvest stage, the dry matter, chlorophyll, sugars, fatty acids and organic acids content in leaves was measured. Regarding dry matter content, significant differences were observed among the ecotypes, with mean values ranging from 6.3 to 8.3%. Differences were also observed in chlorophyll a, b and total chlorophyll, with ecotypes B and D having the highest content comparing to ecotypes A and C. Sugars content differed among the ecotypes for all the detected sugars (glucose, fructose, sucrose) and the total sugars content. Ascorbic acid was detected only in the case of ecotypes B and C, whereas in the other two ecotypes only traces were detected. Finally, regarding tocopherols content, significant differences were observed for both α- tocopherol, with ecotype B having the highest content followed by ecotype C, and δ- tocopherol, where the highest content was observed for ecotype C. For total tocopherols, ecotype C had also the highest content comparing to the other ecotypes. Fatty acids content did not differ among the studied ecotypes, for both the content of the main fatty acids (α-linolenic, linoleic and palmitic acid) and the monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and total fatty acids (TFA) content. In conclusion, genotype has an important effect on nutritional and chemical composition of ‘stamnagathi’ ecotypes, and special interest rises for detecting and evaluating ecotypes with high quality profile for commercial cultivation.info:eu-repo/semantics/publishedVersio

Daily heliotropic movements assist gas exchange and productive responses in DREB1A soybean plants under drought stress in the greenhouse.

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Hyperspectral Imaging Techniques for Rapid Identification of Arabidopsis Mutants with Altered Leaf Pigment Status

The spectral reflectance signature of living organisms provides information that closely reflects their physiological status. Because of its high potential for the estimation of geomorphic biological parameters, particularly of gross photosynthesis of plants, two-dimensional spectroscopy, via the use of hyperspectral instruments, has been widely used in remote sensing applications. In genetics research, in contrast, the reflectance phenotype has rarely been the subject of quantitative analysis; its potential for illuminating the pathway leading from the gene to phenotype remains largely unexplored. In this study, we employed hyperspectral imaging techniques to identify Arabidopsis mutants with altered leaf pigment status. The techniques are comprised of two modes; the first is referred to as the ‘targeted mode’ and the second as the ‘non-targeted mode’. The ‘targeted’ mode is aimed at visualizing individual concentrations and compositional parameters of leaf pigments based on reflectance indices (RIs) developed for Chls a and b, carotenoids and anthocyanins. The ‘non-targeted’ mode highlights differences in reflectance spectra of leaf samples relative to reference spectra from the wild-type leaves. Through the latter approach, three mutant lines with weak irregular reflectance phenotypes, that are hardly identifiable by simple observation, were isolated. Analysis of these and other mutants revealed that the RI-based targeted pigment estimation was robust at least against changes in trichome density, but was confounded by genetic defects in chloroplast photorelocation movement. Notwithstanding such a limitation, the techniques presented here provide rapid and high-sensitive means to identify genetic mechanisms that coordinate leaf pigment status with developmental stages and/or environmental stress conditions

Meta-analysis of the detection of plant pigment concentrations using hyperspectral remotely sensed data

Passive optical hyperspectral remote sensing of plant pigments offers potential for understanding plant ecophysiological processes across a range of spatial scales. Following a number of decades of research in this field, this paper undertakes a systematic meta-analysis of 85 articles to determine whether passive optical hyperspectral remote sensing techniques are sufficiently well developed to quantify individual plant pigments, which operational solutions are available for wider plant science and the areas which now require greater focus. The findings indicate that predictive relationships are strong for all pigments at the leaf scale but these decrease and become more variable across pigment types at the canopy and landscape scales. At leaf scale it is clear that specific sets of optimal wavelengths can be recommended for operational methodologies: total chlorophyll and chlorophyll a quantification is based on reflectance in the green (550–560nm) and red edge (680–750nm) regions; chlorophyll b on the red, (630–660nm), red edge (670–710nm) and the near-infrared (800–810nm); carotenoids on the 500–580nm region; and anthocyanins on the green (550–560nm), red edge (700–710nm) and near-infrared (780–790nm). For total chlorophyll the optimal wavelengths are valid across canopy and landscape scales and there is some evidence that the same applies for chlorophyll a

A novel pattern of leaf movement: The case of Capparis spinosa L.

A novel type of heliotropic leaf movement is presented for Capparis spinosa L., a summer perennial shrub of Mediterranean and arid ecosystems. In contrast to plants that demonstrate uniform diaheliotropic and/or paraheliotropic movement for all their foliage, the alternate leaves of C. spinosa follow different movement patterns according to their stem azimuth and the side of the stem that they come from (cluster). Additionally, leaf movement for each cluster may not be uniform throughout the day, showing diaheliotropic characteristics during half of the day and paraheliotropic characteristics during the rest of the day. In an attempt to reveal the adaptive significance of this differential movement pattern, the following hypotheses were tested: (i) increase of the intercepted solar radiation and photosynthesis, (ii) avoidance of photoinhibitory conditions, (iii) amelioration of water-use efficiency and (iv) adjustment of the leaf temperature microenvironment. No evidence was found in support of the first two hypotheses. A slight difference toward a better water use was found for the moving compared with immobilized leaves, in combination with a better cooling effect. © 2016 The Author 2016. Published by Oxford University Press. All rights reserved

Climatic Drivers of the Complex Phenology of the Mediterranean Semi-Deciduous Shrub Phlomis fruticosa Based on Satellite-Derived EVI

A 21-year Enhanced Vegetation Index (EVI) time-series produced from MODIS satellite images was used to study the complex phenological cycle of the drought semi-deciduous shrub Phlomis fruticosa and additionally to identify and compare phenological events between two Mediterranean sites with different microclimates. In the more xeric Araxos site, spring leaf fall starts earlier, autumn revival occurs later, and the dry period is longer, compared with the more favorable Louros site. Accordingly, the control of climatic factors on phenological events was examined and found that the Araxos site is mostly influenced by rain related events while Louros site by both rain and temperature. Spring phenological events showed significant shifts at a rate of 1–4.9 days per year in Araxos, which were positively related to trends for decreasing spring precipitation and increasing summer temperature. Furthermore, the climatic control on the inter-annual EVI fluctuation was examined through multiple linear regression and machine learning approaches. For both sites, temperature during the previous 2–3 months and rain days of the previous 3 months were identified as the main drivers of the EVI profile. Our results emphasize the importance of focusing on a single species and small-spatial-scale information in connecting vegetation responses to the climate crisis