The Influence of Phytohormones on the Efficiency of Callus Formation, Its Morphologically Properties and Content of Bioactive Compounds in In Vitro Cultures of Daucus carota L.

The significance of cultivar colour (orange and yellow), the application of MgO during field cultivation and chosen phytohormones in the callus cultivation medium are investigated in the present study, with respect to the antioxidative properties of the obtained callus. Callus cultivation are examined as an alternative method for the production of plant antioxidant compounds. Cultivar choice was most significant for callus production and the synthesis of health-promoting metabolites. The best combination, with respect to the induction efficacy and antioxidant properties measured as a synthetic value by Multidimensional Comparative Analysis (MCA), was found in the callus of cultivar ‘Flacoro’, cultivated without MgO fertilization and on a medium with kinetin (KIN) and 1-naphthaleneacetic acid (NAA) (MCA-value 0.465). The worst performance was found for cultivar ‘Yello Mello’, independent of the applied phythormones (averaged MCA-value 0.839) and for the cultivar ‘Flacoro’ fertilized with MgO and independent of growth hormones (averaged MCA-value 0.810)

Nutritional and Sensory Quality of Two Types of Cress Microgreens Depending on the Mineral Nutrition

The present study addressed the combination of nutritional and sensory quality assessment of radish and garden cress as microgreens cultivated in different amounts of mineral nutrients under conditions that can be realized in a private household. The content of value adding compounds was determined by means of chemical analyses. Total flavor impression and visual appearance were rated by untrained consumer tests. In cotyledons of radish cress (Raphanus sativus L.), carotenoid, total phenols, nitrate contents, and antioxidant capacity decreased significantly with decreasing mineral content in the nutrient solution, whereas, in stems, total phenols and anthocyanin contents rose and nitrate content decreased significantly with decreasing mineral content. In garden cress (Lepidium sativum L.), carotenoid and nitrate contents decreased and anthocyanin content increased significantly with decreasing mineral content, indicating that the response of value adding compounds to changing amounts of minerals in the nutrient solution depends on the compound of interest, plant species, and even the plant organ of a species. The sensory quality of the studied microgreens was generally rated highest when mineral content in the nutrient solution was highest, indicating that sensory quality is not necessarily identical with nutritional quality. Considering the common practice in private households, cultivation with tap water represents an attractive compromise for nutritional and sensory quality in case of garden cress, whereas, for radish cress, the application of 25% modified Hoagland solution is recommended

The Influence of Phytohormones on the Efficiency of Callus Formation, Its Morphologically Properties and Content of Bioactive Compounds in In Vitro Cultures of <i>Daucus carota</i> L.

The significance of cultivar colour (orange and yellow), the application of MgO during field cultivation and chosen phytohormones in the callus cultivation medium are investigated in the present study, with respect to the antioxidative properties of the obtained callus. Callus cultivation are examined as an alternative method for the production of plant antioxidant compounds. Cultivar choice was most significant for callus production and the synthesis of health-promoting metabolites. The best combination, with respect to the induction efficacy and antioxidant properties measured as a synthetic value by Multidimensional Comparative Analysis (MCA), was found in the callus of cultivar ‘Flacoro’, cultivated without MgO fertilization and on a medium with kinetin (KIN) and 1-naphthaleneacetic acid (NAA) (MCA-value 0.465). The worst performance was found for cultivar ‘Yello Mello’, independent of the applied phythormones (averaged MCA-value 0.839) and for the cultivar ‘Flacoro’ fertilized with MgO and independent of growth hormones (averaged MCA-value 0.810)

Chlorophyll Fluorescence as a Tool to Assess the Regeneration Potential of African Violet Leaf Explants

Micropropagation of many ornamentals has enabled their efficient commercialisation and many problems have been solved by the elaboration of adequate culture protocols. Nevertheless, a non-destructive technique for monitoring the developmental progress of explants would be desirable. The present study focussed on the applicability of chlorophyll fluorescence in leaf explants of African violet (a Saintpaulia ionantha × confusa – hybrid) explanted onto Murashige and Skoog basic medium. The explants that survived on the medium without additional phytohormones had the capacity to develop further into two different kinds of explants: light green explants, characterized by a non-regular size growth and stiffer appearance, and dark green explants capable of organogenesis. Compared to the source leaves of African violet plants, explants were characterized by reduced chlorophyll (Chl) and carotenoid (Car) contents as well as a tendency towards a higher Car/Chl ratio. The Chl a/b ratio decreased significantly in the light green explants. A reduction of maximum quantum efficiency of photosystem II (Fv/Fm) accompanied by a high percentage (&gt; 50%) of thermal energy dissipation as a consequence of an elevated light intensity (800 µmol m-2 s-1 quanta) indicated photoinhibition in the light green explants, whereas in the dark green explants the largest percentage (&gt; 50%) of the light energy was dissipated into the fraction of photon energy trapped by ‘closed’ photosystem II reaction centres. These results suggest that the capacity of organogenesis of leaf explants of African violet can be monitored using chlorophyll fluorescence, because it is related to modifications of the photosynthetic system

Antioxidant properties of potato tubers (Solanum tuberosum L.) as a consequence of genetic potential and growing conditions.

The concentrations of the bioactive compounds in potato tubers are determined by both genetic potential and environmental factors. The purpose of the experiment was to determine the influence of organic and integrated production on the expression of the genetic potential with respect to the antioxidant properties of potato tubers and to evaluate its stability under different environmental conditions. This phenotyping was performed on seven new breeding lines (tetraploid clones) and three modern cultivars: Jelly, Satina and Tajfun. The results indicated that production system and location significantly influenced the antioxidant capacity measured by FRAP method. Organic farming and the location Chwałowice were characterized by higher values. Furthermore, anitioxidative capacity measured by FRAP method was correlated with chlorogenic acid content (r = 0.590**) and glutathione fractions, especially with the reduced form (GSH, r = 0.692**). Multidimensional comparative analysis (MCA) proved a better development of antioxidant properties of potato tubers in the organic cultivation system when compared with the integrated. Especially favorable were growing conditions at Boguchwała (organic) and worst at Młochów (integrated). From all investigated varieties, the best antioxidant properties were found in 'Satina' and 'Jelly'. Clones TG-97-403 and 13-VIII-45 developed the weakest health promoting traits

Photosynthetic efficiency of perennial ryegrass (Lolium perenne L.) seedlings in response to Ni and Cd stress

Abstract Perennial ryegrass is a grass species used to establish lawns in urban areas where pollution is a major environmental problems. Cadmium (Cd) and nickel (Ni) contribute significantly to these pollutants and may cause photosynthetic limitation. The main objective of this work was to perform a comprehensive analysis of photosynthetic efficiency of perennial ryegrass seedlings under Cd and Ni stress. Some of the main indices of photosynthetic efficiency (prompt and delayed chlorophyll-a fluorescence signals and modulated reflectance at 820 nm) were compared with growth parameters. Two cultivars were tested: 'Niga' and 'Nira'. A decrease in photosystem (PS) II and PSI activity was observed. This was due to an increase in nonradiative dissipation of the PSII antenna, a decrease in PSII antenna size, or a decrease in the number of photosynthetic complexes with fully closed PSII RCs. Efficiency of electron transport was decreased. The effect on the modulated reflectance signal could indicate a restriction in electron flow from PSII to PSI. The correlation between photosynthetic efficiency parameters, such as Area, Fo, Fm, and Fv, and growth parameters, confirmed that some photosynthetic efficiency parameters can be used as indicators for early detection of heavy metal effects