Biomass and Leaf Acclimations to Ultraviolet Solar Radiation in Juvenile Plants of Coffea arabica and C. canephora

Despite the negative impacts of increased ultraviolet radiation intensity on plants, these organisms continue to grow and produce under the increased environmental UV levels. We hypothesized that ambient UV intensity can generate acclimations in plant growth, leaf morphology, and photochemical functioning in modern genotypes of Coffea arabica and C. canephora. Coffee plants were cultivated for ca. six months in a mini greenhouse under either near ambient (UVam) or reduced (UVre) ultraviolet regimes. At the plant scale, C. canephora was substantially more impacted by UVam when compared to C. arabica, investing more carbon in all juvenile plant components than under UVre. When subjected to UVam, both species showed anatomic adjustments at the leaf scale, such as increases in stomatal density in C. canephora, at the abaxial and adaxial cuticles in both species, and abaxial epidermal thickening in C. arabica, although without apparent impact on the thickness of palisade and spongy parenchyma. Surprisingly, C. arabica showed more efficient energy dissipation mechanism under UVam than C. canephora. UVam promoted elevated protective carotenoid content and a greater use of energy through photochemistry in both species, as reflected in the photochemical quenching increases. This was associated with an altered chlorophyll a/b ratio (significantly only in C. arabica) that likely promoted a greater capability to light energy capture. Therefore, UV levels promoted different modifications between the two Coffea sp. regarding plant biomass production and leaf morphology, including a few photochemical differences between species, suggesting that modifications at plant and leaf scale acted as an acclimation response to actual UV intensity.

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Ploidy levels in Citrus clementine affects leaf morphology, stomatal density and water content

Theoretical and Experimental Plant Physiology ◽

10.1590/s2197-00252013000400006 ◽

2013 ◽

Vol 25 (4) ◽

pp. 283-290 ◽

Cited By ~ 13

Author(s):

Diego Padoan ◽

Amr Mossad ◽

Benedetta Chiancone ◽

Maria Antonietta Germana ◽

Patan Shaik Sha Valli Khan

Keyword(s):

Water Content ◽

Leaf Morphology ◽

Stomatal Density ◽

Ploidy Levels

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Arsenic Application Changed Growth, Photo-Synthetic Pigments and Antioxidant Enzymes Activity in Sorghum (Sorghum bicolor L.) Under Salinity Stress

Scientia Agriculturae Bohemica ◽

10.2478/sab-2019-0021 ◽

2019 ◽

Vol 50 (3) ◽

pp. 155-163 ◽

Cited By ~ 1

Author(s):

B. Talebi ◽

M. Heidari ◽

H. Ghorbani

Keyword(s):

Plant Biomass ◽

Dry Weight ◽

Carotenoid Content ◽

Soluble Carbohydrates ◽

Soluble Carbohydrate ◽

Guaiacol Peroxidase ◽

Anthocyanin Content ◽

Synthetic Pigments ◽

Root Tissues ◽

Gpx Activity

Abstract The elevation of arsenic (As) content in soils is of considerable concern with respect to its uptake by plant and subsequent entry into wildlife and human food chains. The treatment of sorghum seedlings with As as NaH2As4O. 7H2O at various concentrations (A1 = 0, A2 = 20, A3 = 40 and A4 = 60 mg As kg−1 soil) and salinity at four different levels (S1 = 0, S2 = 3, S3 = 6 and S3 = 9 dS m−1) reduced fresh and dry weights of sorghum plants. The co-application of As and salinity increased the guaiacol peroxidase (GPX) activity in shoot and root tissues. The highest GPX activity in shoot and root tissues was obtained at S2A4 and S3A3 treatments, respectively. The activity of catalase (CAT) in shoot was not changed, but unlike the GPX activity, salinity and As decreased the CAT activity in root tissues. Concerning the photosynthesis pigments, salinity had no effect on the chlorophyll ‘a’, chlorophyll ‘b’ and carotenoid content in leaves, but the As treatment significantly decreased the content of both chlorophyll types. Salinity increased the anthocyanin content in leaves. There were negative correlation between soluble carbohydrates (r2 = −0.78**) and stomata conductance (r2 = −0.45**) and dry weight of the plant biomass in this study. By increasing the salinity and As concentration in root medium, soluble carbohydrate in leaves increased but salinity decreased the leaf stomata conductance.

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Stomatal aperture can compensate altered stomatal density in Arabidopsis thaliana at growth light conditions

Functional Plant Biology ◽

10.1071/fp06078 ◽

2006 ◽

Vol 33 (11) ◽

pp. 1037 ◽

Cited By ~ 54

Author(s):

Dirk Büssis ◽

Uritza von Groll ◽

Joachim Fisahn ◽

Thomas Altmann

Keyword(s):

Arabidopsis Thaliana ◽

Stomatal Conductance ◽

Stomatal Density ◽

Co2 Assimilation ◽

High Light ◽

Stomatal Aperture ◽

Photochemical Quenching ◽

Light Conditions ◽

Wild Type ◽

Light Intensities

Stomatal density of transgenic Arabidopsis thaliana plants over-expressing the SDD1 (stomatal density and distribution) gene was reduced to 40% and in the sdd1-1 mutant increased to 300% of the wild type. CO2 assimilation rate and stomatal conductance of over-expressers and the sdd1-1 mutant were unchanged compared with wild types when measured under the light conditions the plants were exposed to during growth. Lower stomatal density was compensated for by increased stomatal aperture and conversely, increased stomatal density was compensated for by reduced stomatal aperture. At high light intensities the assimilation rates and stomatal conductance of SDD1 over-expressers were reduced to 80% of those in wild type plants. Areas beneath stomata and patches lacking stomata were analysed separately. In areas without stomata, maximum fluorescence yield (Fv / Fm) and quantum yield of photosystem II (Φ PSII) were significantly lower than in areas beneath stomata. In areas beneath stomata, Fv / Fm and Φ PSII were identical to levels measured in wild type leaves. At high light intensities over-expressers showed decreased photochemical quenching (qP) compared with wild types. However, the decrease of qP was significantly stronger in areas without stomata than in mesophyll areas beneath stomata. At high CO2 partial pressures and high light intensities CO2 assimilation rates of SDD1 over-expressers did not reach wild type levels. These results indicate that photosynthesis in SDD1 over-expressers was reduced because of limiting CO2 in areas furthest from stomata at high light.

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Application of Nano-Silicon Dioxide Improves Salt Stress Tolerance in Strawberry Plants

Agronomy ◽

10.3390/agronomy9050246 ◽

2019 ◽

Vol 9 (5) ◽

pp. 246 ◽

Cited By ~ 10

Author(s):

Saber Avestan ◽

Mahmood Ghasemnezhad ◽

Masoud Esfahani ◽

Caitlin S. Byrt

Keyword(s):

Salt Stress ◽

Silicon Dioxide ◽

Chlorophyll Content ◽

Plant Biomass ◽

Epicuticular Wax ◽

Carotenoid Content ◽

Plant Tolerance ◽

Sem Images ◽

Nano Silicon ◽

Epicuticular Wax Layer

Silicon application can improve productivity outcomes for salt stressed plants. Here, we describe how strawberry plants respond to treatments including various combinations of salt stress and nano-silicon dioxide, and assess whether nano-silicon dioxide improves strawberry plant tolerance to salt stress. Strawberry plants were treated with salt (0, 25 or 50 mM NaCl), and the nano-silicon dioxide treatments were applied to the strawberry plants before (0, 50 and 100 mg L−1) or after (0 and 50 mg L−1) flowering. The salt stress treatments reduced plant biomass, chlorophyll content, and leaf relative water content (RWC) as expected. Relative to control (no NaCl) plants the salt treated plants had 10% lower membrane stability index (MSI), 81% greater proline content, and 54% greater cuticular transpiration; as well as increased canopy temperature and changes in the structure of the epicuticular wax layer. The plants treated with nano-silicon dioxide were better able to maintain epicuticular wax structure, chlorophyll content, and carotenoid content and accumulated less proline relative to plants treated only with salt and no nano-silicon dioxide. Analysis of scanning electron microscopic (SEM) images revealed that the salt treatments resulted in changes in epicuticular wax type and thickness, and that the application of nano-silicon dioxide suppressed the adverse effects of salinity on the epicuticular wax layer. Nano-silicon dioxide treated salt stressed plants had increased irregular (smoother) crystal wax deposits in their epicuticular layer. Together these observations indicate that application of nano-silicon dioxide can limit the adverse anatomical and biochemical changes related to salt stress impacts on strawberry plants and that this is, in part, associated with epicuticular wax deposition.

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Investigation of Pellet Properties Produced from a Mix of Straw and Paper Sludge

Applied Sciences ◽

10.3390/app10165450 ◽

2020 ◽

Vol 10 (16) ◽

pp. 5450 ◽

Cited By ~ 1

Author(s):

Radovan Nosek ◽

Sebastian Werle ◽

Aleksandra Borsukiewicz ◽

Agnieszka Żelazna ◽

Grzegorz Łagód

Keyword(s):

Melting Temperature ◽

Heat Exchangers ◽

Fossil Fuels ◽

Plant Biomass ◽

Biomass Combustion ◽

Paper Sludge ◽

Wood Pellets ◽

Positive Effects ◽

Negative Impacts ◽

Global Energy Consumption

Global energy consumption is increasing every year, and, despite their many negative impacts, fossil fuels are a major source of energy, but their reserves are gradually depleting. One of the promising but underutilized resources is plant biomass (phytomass). The main problem of plant biomass combustion is the low melting temperature of ash, but there are also problems with corrosion of heat exchangers and clogging of heat-exchanging surfaces. This work is concerned with the production of straw pellets in order to increase the melting temperature of ash by adding an additive. The paper sludge contains substances that can increase the melting point of ash and was therefore added to the pellet samples. This additive was mixed with straw in ratios from 90:10, 80:20 and 70:30 (straw/paper sludge). The use of paper sludge showed positive effects on increasing the melting temperature of the ash samples. The deformation temperature of the ash has already risen from 1020 to 1260 °C after the addition of 10% sludge, which is comparable to wood pellets.

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Quality and Intensity of Light in the In Vitro Development of Microstumps of Eucalyptus urophylla in a Photoautotrophic System

Forest Science ◽

10.1093/forsci/fxaa027 ◽

2020 ◽

Vol 66 (6) ◽

pp. 754-760 ◽

Cited By ~ 1

Author(s):

Natane A Miranda ◽

Aloisio Xavier ◽

Wagner C Otoni ◽

Ricardo Gallo ◽

Kellen C Gatti ◽

...

Keyword(s):

Plant Growth ◽

Light Quality ◽

Stomatal Density ◽

Carotenoid Content ◽

Fluorescent Light ◽

Eucalyptus Urophylla ◽

Light Emitting ◽

Fluorescent Lamps ◽

Number Of Shoots

Abstract The quality and quantity of light are important factors in controlling in vitro plant growth in photoautotrophic systems. The aim of this study was to evaluate the influence of light quality (fluorescent, white, red, blue, red/blue, and distant red) on microstumps of a Eucalyptus urophylla clone in an in vitro photoautotrophic system, as well as the intensity of fluorescent light (60, 85, 100, and 140 μmol m–2 s–1) in the growth and production of microcutting. The number of shoots and microcutting, the size of the largest shoot, the stomatal density, chlorophyll, and carotenoid content were analyzed. Light quality altered plant growth, and fluorescent light intensity did not affect the microstumps’ production during the evaluation period. In white light-emitting diode (LED) light, there was higher production of carotenoids, with a lower initial production of microcuttings. A smaller number of shoots were obtained in blue LED. In general, the different qualities and light intensities tested allowed for the growth of the Eucalyptus urophylla clone grown in vitro, making it possible to obtain microcuttings under photoautotrophic cultivation. Study Implications In vitro propagation is a stressful process for plants and has limitations for commercial-scale Eucalyptus production. Fluorescent lamps, closed containers, and high sucrose concentrations are traditionally used. To reduce costs and improve production, the use of efficient light sources and photoautotrophic cultivation systems become alternatives. This study investigated the influence of light on the in vitro growth of a Eucalyptus clone in a photoautotrophic system. The quality was more important than the intensity of light. Foresters will be able to indicate the use of LEDs (light-emitting diodes) as a replacement for fluorescent lamps. This approach is useful in enhancing micropropagation techniques.

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Do leaf traits in two Dalbergia species present differential plasticity in relation to light according to their habitat of origin?

Australian Journal of Botany ◽

10.1071/bt13248 ◽

2013 ◽

Vol 61 (8) ◽

pp. 592 ◽

Cited By ~ 5

Author(s):

Ana Silvia Franco Pinheiro Moreira ◽

Ana Clara Luppi Queiroz ◽

Fernanda de Vasconcelos Barros ◽

Maíra Figueiredo Goulart ◽

José Pires de Lemos-Filho

Keyword(s):

Phenotypic Plasticity ◽

Gas Exchange ◽

Stomatal Density ◽

Common Garden ◽

Leaf Traits ◽

Light Interception ◽

High Plasticity ◽

Forest Species ◽

Palisade And Spongy Parenchyma ◽

Changing Light

The phenotypic plasticity to light of two congeneric species of leguminous trees from distinct habitats was evaluated in a common-garden experiment. For that, we assessed the following two groups of leaf morphological and anatomical traits of 1-year-old seedlings: (1) traits related to light interception (tissues thickness and leaflet mass per area), and (2) traits related to gas exchange (number of leaflets per leaf and measurements of stomatal size and density). Dalbergia nigra (Vell.) Allemão ex Benth. is an endemic Atlantic forest species, and D. miscolobium Benth. is a typical cerrado species. Both were grown under shade and full-sunlight conditions. The phenotypic plasticity of leaves was determined by a relative distance plasticity index (RDPI). For both species, sun leaflets were thicker than shade ones, and only D. nigra presented lower values for stomatal density (nst), percentage of the leaflet area occupied by stomatal pores (nast) and estimated stomatal conductance (gst) under shade conditions. The forest species (D. nigra) had higher plasticity for variables related to gas exchange (number of leaflets per leaf, nst, ast, nast and gst), whereas the cerrado species (D. miscolobium) had higher plasticity for variables related to light interception, such as leaflet mass per area, leaflet thickness and palisade and spongy parenchyma thickness. The degree of plasticity was different for each analysed parameter, and not used to define which species is more plastic. The leaf traits of D. nigra and D. miscolobium that showed high plasticity were related to resources that are not limiting to improve its photosynthesis in a changing light environment.

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Pot size matters: a meta-analysis of the effects of rooting volume on plant growth

Functional Plant Biology ◽

10.1071/fp12049 ◽

2012 ◽

Vol 39 (11) ◽

pp. 839 ◽

Cited By ~ 325

Author(s):

Hendrik Poorter ◽

Jonas Bühler ◽

Dagmar van Dusschoten ◽

José Climent ◽

Johannes A. Postma

Keyword(s):

Plant Growth ◽

Size Effects ◽

Leaf Morphology ◽

Plant Biomass ◽

Meta Analysis ◽

Plant Biology ◽

Research Practice ◽

Unit Leaf ◽

Pot Size ◽

Lines Of Evidence

The majority of experiments in plant biology use plants grown in some kind of container or pot. We conducted a meta-analysis on 65 studies that analysed the effect of pot size on growth and underlying variables. On average, a doubling of the pot size increased biomass production by 43%. Further analysis of pot size effects on the underlying components of growth suggests that reduced growth in smaller pots is caused mainly by a reduction in photosynthesis per unit leaf area, rather than by changes in leaf morphology or biomass allocation. The appropriate pot size will logically depend on the size of the plants growing in them. Based on various lines of evidence we suggest that an appropriate pot size is one in which the plant biomass does not exceed 1 g L–1. In current research practice ~65% of the experiments exceed that threshold. We suggest that researchers need to carefully consider the pot size in their experiments, as small pots may change experimental results and defy the purpose of the experiment.

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Effect of SiO2 nanoparticles on drought resistance in hawthorn seedlings

Forest Research Papers ◽

10.1515/frp-2015-0034 ◽

2015 ◽

Vol 76 (4) ◽

pp. 350-359 ◽

Cited By ~ 16

Author(s):

Peyman Ashkavand ◽

Masoud Tabari ◽

Mehrdad Zarafshar ◽

Ivana Tomášková ◽

Daniel Struve

Keyword(s):

Drought Stress ◽

Drought Resistance ◽

Crop Production ◽

Plant Biomass ◽

Proline Content ◽

Carotenoid Content ◽

Biochemical Basis ◽

Positive Effects ◽

Drought Conditions ◽

Physiological And Biochemical

Abstract Drought is a significant factor limiting crop production in arid regions while hawthorns (Crataegus sp.) are an important component of such region’s forests. Therefore, treatments that increase hawthorn drought resistance may also increase transplanting success. Thus, the physiological and biochemical responses of hawthorn seedlings to a factorial combination of different concentrations of silica nanoparticles (SNPs at 0, 10, 50 and 100 mg L−1) and three soil moisture treatments (without stress, moderate stress and severe stress) were investigated. Seedlings were irrigated with one of the four concentrations of SNPs for 45 days before exposing them to drought stress. Photosynthesis parameters, malondialdehyde (MDA), relative water content (RWC), membrane electrolyte leakage (ELI) as well as chlorophyll, carotenoid, carbohydrate and proline content were determined. At the end of the experiment, positive effects by SNP pre-treatment on physiological indexes were observed during drought stress. Under drought conditions, the effect of SNPs on photosynthetic rate and stomatal conductance was evident. Although the SNPs increased plant biomass, xylem water potential and MDA content, especially under drought conditions, RWC and ELI were not affected by the SNP pre-treatments. Seedlings pre-treated with SNPs had a decreased carbohydrate and proline content under all water regimes, but especially so under drought. Total chlorophyll content and carotenoid content did not change among the treatments. Generally, the findings imply that SNPs play a positive role in maintaining critical physiological and biochemical functions in hawthorn seedlings under drought stress conditions. However, more studies are needed before the physiological and biochemical basis of induced drought resistance can be determined.

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Cooler temperatures favour growth of wild leek (Allium tricoccum), a deciduous forest spring ephemeral

Botany ◽

10.1139/b2012-089 ◽

2012 ◽

Vol 90 (11) ◽

pp. 1125-1132 ◽

Cited By ~ 9

Author(s):

Antoine Bernatchez ◽

Line Lapointe

Keyword(s):

Temperature Regime ◽

Deciduous Forest ◽

Plant Biomass ◽

Photochemical Efficiency ◽

Early Spring ◽

Photochemical Quenching ◽

Spring Ephemerals ◽

Spring Ephemeral ◽

Short Period ◽

Allium Tricoccum

Allium tricoccum Aiton is a common spring ephemeral of hardwood deciduous forests of northeastern North America. It takes advantage of the short period of high light conditions between snowmelt and canopy closure to complete its vegetative life cycle and accumulate carbohydrate reserves for the following year. Previous studies on other spring ephemerals have shown that growth of these species is enhanced when grown at low temperature, typical of very early spring. We thus quantified the effect of three growth temperature regimes, i.e., 18 °C day – 14 °C night, 12 °C day – 8 °C night, and 8 °C day – 6 °C night, which have previously been tested on Erythronium americanum, another spring ephemeral. Gas exchange, chlorophyll a fluorescence, and plant biomass were measured repeatedly throughout the growth season. Growth was greatest under the 12 °C day – 8 °C night temperature regime, consistent with enhanced net photosynthetic rates (Pn), photochemical quenching (qP), and photochemical efficiency of photosynthesis (ΦPSII) at this temperature regime throughout the season. Pn was similar at 18 °C day – 14 °C night and 8 °C day – 6 °C night, but leaves had a greater duration at 8 °C day – 6 °C night; however, bulb biomass was not greater at 8 °C day – 6 °C night than at 18 °C day – 14 °C night. This study corroborates the general sensitivity of spring ephemerals to warmer temperatures. It also highlights species differences that might be caused by their specific carbon metabolism at the bulb level.

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