Publications by authors named "Evandro Alexandre Fortini"

6 Publications

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Anatomy, Flow Cytometry, and X-Ray Tomography Reveal Tissue Organization and Ploidy Distribution in Long-Term Cultures of Species.

Front Plant Sci 2020 31;11:1314. Epub 2020 Aug 31.

Laboratory of Plant Tissue Culture II-BIOAGRO, Plant Biology Department, Federal University of Viçosa (UFV), Viçosa, Brazil.

Cacti have a highly specialized stem that enables survival during extended dry periods. Despite the ornamental value of cacti and the fact that stems represent the main source of explants in tissue culture, there are no studies on their morpho-anatomical and cytological characteristics in . The present study seeks to address the occurrence of cells with mixed ploidy level in cacti tissues. Specifically, we aim to understand how stem tissue is organized, how mixoploidy is distributed when present, and whether detected patterns of ploidy change after long periods of culture. To analyze tissue organization, and plants that had been germinated and cultivated were analyzed for stem structure using toluidine blue, Xylidine Ponceau, Periodic Acid Schiff, ruthenium red, and acid floroglucin. To investigate patterns of ploidy, apical, medial, and basal zones of the stem, as well as, periphery, cortex, and stele (vascular tissue and pith) regions of the stem and root apexes from four- and ten-year old cultured were analyzed by flow cytometry. X-ray micro-computed tomography (XRµCT) was performed with fragments of stems from both species. The scarcity of support elements (, sclereids and fibers) indicates that epidermis, hypodermis, and wide-band tracheids present in cortical vascular bundles and stele, as well as water stored in aquifer parenchyma cells along the cortex, provide mechanical support to the stem. Parenchyma cells increase in volume with a four-fold increase in ploidy. and exhibit the same pattern of cell ploidy irrespective of topophysical region or age, but there is a marked difference in ploidy between the stem periphery (epidermis and hypodermis), cortex, stele, and roots. Mixoploidy in is not related to the age of the culture, but is a developmental trait, whereby endocycles promote cell differentiation to accumulate valuable water.
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http://dx.doi.org/10.3389/fpls.2020.01314DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7488924PMC
August 2020

Irradiance-driven 20-hydroxyecdysone production and morphophysiological changes in Pfaffia glomerata plants grown in vitro.

Protoplasma 2021 Jan 25;258(1):151-167. Epub 2020 Sep 25.

Departamento de Biologia Vegetal/BIOAGRO, Universidade Federal de Viçosa, Viçosa, MG, 36570-900, Brazil.

Pfaffia glomerata possesses potential pharmacological and medicinal properties, mainly owing to the secondary metabolite 20-hydroxyecdysone (20E). Increasing production of biomass and 20E is important for industrial purposes. This study aimed to evaluate the influence of irradiance on plant morphology and production of 20E in P. glomerata grown in vitro. Nodal segments of accessions 22 and 43 (Ac22 and Ac43) were inoculated in culture medium containing MS salts and vitamins. Cultures were maintained at 25 ± 2 °C under a 16-h photoperiod and subjected to irradiance treatments of 65, 130, and 200 μmol m s by fluorescent lamps. After 30 days, growth parameters, pigment content, stomatal density, in vitro photosynthesis, metabolites content, and morphoanatomy were assessed. Notably, Ac22 plants exhibited 10-fold higher 20E production when cultivated at 200 μmol m s than at 65 μmol m s, evidencing the importance of light quantity for the accumulation of this metabolite. 20E production was twice as high in Ac22 as in Ac43 plants although both accessions responded positively to higher irradiance. Growth under 200 μmol m s stimulated photosynthesis and consequent biomass accumulation, but lowered carotenoids and anthocyanins. Furthermore, increasing irradiance enhanced the number of palisade and spongy parenchyma cells, enhancing the overall growth of P. glomerata. Graphical abstract.
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http://dx.doi.org/10.1007/s00709-020-01558-1DOI Listing
January 2021

Leaf development stages and ontogenetic changes in passionfruit (Passiflora edulis Sims.) are detected by narrowband spectral signal.

J Photochem Photobiol B 2020 Aug 10;209:111931. Epub 2020 Jun 10.

Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil. Electronic address:

During shoot development, leaves undergo various ontogenetic changes, including variation in size, shape, and geometry. Passiflora edulis (passionfruit) is a heteroblastic species, which means that it experiences conspicuous changes throughout development, enabling a morphological distinction between the juvenile and adult vegetative phases. Quantification of heteroblasty requires a practical, inexpensive, reliable, and non-destructive method, such as remote sensing. Moreover, relationships among ontogenetic changes and spectral signal at leaf level can be scaled up to support precision agriculture in passion fruit crops. In the present study, we used laboratory spectroscopic measurements (400-2500 nm) and narrowband vegetation indexes (or hyperspectral vegetation indexes - HVIs) to evaluate ontogenetic changes related to development and aging in P. edulis leaves. We also assessed leaf pigment concentration to further support the application of biochemical-related narrowband indexes. We report that 30-d-old leaves can be discriminated into developmental stages through their spectral signals. MSI (Moisture Stress Index) and NDVI (Normalized Difference Vegetation Index ρ750) contribute most to the variation of age (15 to 30-d-old leaves) and developmental stage (phytomer positions along the plant axis) in passionfruit leaves. PRI (Photochemical Reflectance Index) played an important role in detecting age and development alterations, including heteroblasty. A biochemical and spectral comparison of pigments revealed that spectroscopy offered potential for diagnosing phenology in P. edulis, as some narrowband indexes correlated strongly with chlorophylls and carotenoids content. Narrowband vegetation indexes are found to be a suitable tool for monitoring passionfruit crops.
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http://dx.doi.org/10.1016/j.jphotobiol.2020.111931DOI Listing
August 2020

Blue and red light affects morphogenesis and 20-hydroxyecdisone content of in vitro Pfaffia glomerata accessions.

J Photochem Photobiol B 2020 Jan 24;203:111761. Epub 2019 Dec 24.

Departamento de Biologia Vegetal/BIOAGRO, Universidade Federal de Viçosa, Viçosa, MG, Brazil. Electronic address:

The combination of different colors from light-emitting diodes (LEDs) may influence growth and production of secondary metabolites in plants. In the present study, the effect of light quality on morphophysiology and content of 20-hydroxyecdysone (20E), a phytoecdysteroid, was evaluated in accessions of an endangered medicinal species, Pfaffia glomerata, grown in vitro. Two accessions (Ac22 and Ac43) were cultured in vitro under three different ratios of red (R) and blue (B) LEDs: (i) 1R:1B, (ii) 1R:3B, and (iii) 3R:1B. An equal ratio of red and blue light (1R:1B) increased biomass accumulation, anthocyanin content, and 20E production (by 30-40%). Moreover, 1R:1B treatment increased the size of vascular bundles and vessel elements, as well as strengthened xylem lignification and thickening of the cell wall of shoots. The 1R:3B treatment induced the highest photosynthetic and electron transport rates and enhanced the activity of oxidative stress-related enzymes. Total Chl content, Chl/Car ratio, and NPQ varied more by accession type than by light source. Spectral quality affected primary metabolism differently in each accession. Specifically, in Ac22 plants, fructose content was higher under 1R:1B and 1R:3B treatments, whereas starch accumulation was higher under 1R:3B, and sucrose under 3R:1B. In Ac43 plants, sugars were not influenced by light spectral quality, but starch content was higher under 3R:1B conditions. In conclusion, red and blue LEDs enhance biomass and 20E production in P. glomerata grown in vitro.
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http://dx.doi.org/10.1016/j.jphotobiol.2019.111761DOI Listing
January 2020

Accessions of Brazilian ginseng (Pfaffia glomerata) with contrasting anthocyanin content behave differently in growth, antioxidative defense, and 20-hydroxyecdysone levels under UV-B radiation.

Protoplasma 2019 Nov 17;256(6):1557-1571. Epub 2019 Jun 17.

Laboratório de Cultura de Tecidos Vegetais (LCTII), Departamento de Biologia Vegetal/BIOAGRO, Universidade Federal de Viçosa, Campus Universitário, Avenida Peter Henry Rolfs s/n, Viçosa, MG, 36570-900, Brazil.

Ultraviolet-B (UV-B) radiation is an elicitor of secondary metabolites in plant tissue culture, but the effects on 20-hydroxyecdysone (20E) are still unclear. The 20E may show biotechnological, pharmacological, medical, and agrochemical applicability. Here, we use Pfaffia glomerata, a medically important species, to understand the impacts of UV-B radiation on their physiological performance, the expression of key genes involved in the 20E biosynthesis, and the 20E content. Two accessions (A22 and A43) of plants 20 days old grown in vitro were exposed to 0 (control), 2 (6.84 kJ m), and 4 (13.84 kJ m) h UV-B radiation for 20 consecutive days. Our data showed that UV-B reduced glucose concentration in A22 and A43 under 4 h of exposure (29 and 30%, respectively), while sucrose concentration increased (32 and 57%, respectively). UV-B also differentially impacted the accessions (A22 and A43), where the A22 under 4 h of UV-B had reduced total dry weight (8%) and electron transport rate (31%); in contrast, A43 did not change. Also, only A22 had increased POD activity under 4 h of UV-B (66%), as well as increased gene expression of the 20E pathway and the 20E content under 2 and 4 h of UV-B in leaves (28 and 21%, respectively) and roots (16 and 13%, respectively). This differential performance to UV-B can be explained by the contrasting anthocyanin contents. Notably, A43 displayed 56% more anthocyanin to the former, a possible defense against UV-B. In conclusion, UV-B radiation is a potential elicitor for increasing 20E content in P. glomerata grown in vitro.
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http://dx.doi.org/10.1007/s00709-019-01400-3DOI Listing
November 2019

Salinity-induced modifications on growth, physiology and 20-hydroxyecdysone levels in Brazilian-ginseng [Pfaffia glomerata (Spreng.) Pedersen].

Plant Physiol Biochem 2019 Jul 3;140:43-54. Epub 2019 May 3.

Departamento de Biologia Vegetal/BIOAGRO, Universidade Federal de Viçosa, Viçosa, MG, Brazil. Electronic address:

- Salinity is a major threat to agriculture. However, depending on the concentration of soluble salts in soil, increased secondary metabolite levels can occur with no major damages to plant growth and development. The phytoecdysteroid (PE) 20-hydroxyecdysone (20E) is a secondary metabolite with biotechnological, medicinal, pharmaceutical and agrochemical applicability. Here, we characterize the responses (growth and physiology) of Pfaffia glomerata under different NaCl concentrations and examine the production of 20E as affected by salinity. Forty-day-old plants grown in greenhouse were exposed to 0, 120, 240, 360 or 480 mM of NaCl for 11 days. Moderate salinity (i.e., 120 mM of NaCl) led to increased 20E concentrations in leaves (47%) relative to the control with no significant effect on photosynthesis and biomass accumulation, thus allowing improved 20E contents on a per whole-plant basis. In contrast, plants under high salinity (i.e., 240-480 mM of NaCl) displayed similar 20E concentrations in leaves compared to the control, but with marked impairments to biomass accumulation and photosynthetic performance (coupled with decreased sucrose and starch levels) in parallel to nutritional imbalance. High salinity also strongly increased salicylic acid levels, antioxidant enzyme activities, and osmoregulatory status. Regardless of stress severity, 20E production was accompanied by the upregulation of Spook and Phantom genes. Our findings suggest that P. glomerata cultivation in moderate salinity soils can be considered as a suitable agricultural option to increase 20E levels, since metabolic and structural complexity that makes its artificial synthesis very difficult.
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http://dx.doi.org/10.1016/j.plaphy.2019.05.002DOI Listing
July 2019
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