Influence of leaf trichomes on boundary layer conductance and gas-exchange characteristics inMetrosideros polymorpha(Myrtaceae)

Biotropica ◽  
2017 ◽  
Vol 49 (4) ◽  
pp. 482-492 ◽  
Author(s):  
Gaku Amada ◽  
Yusuke Onoda ◽  
Tomoaki Ichie ◽  
Kanehiro Kitayama
Keyword(s):  
Boundary Layer ◽  
Gas Exchange ◽  
Leaf Trichomes ◽  
Gas Exchange Characteristics

scholarly journals Roles of leaf trichomes in heat transfers and gas‐exchange characteristics across environmental gradients

2020 ◽  
Author(s):  
Gaku Amada ◽  
Yoshiko Kosugi ◽  
Kanehiro Kitayama ◽  
Yusuke Onoda
Keyword(s):  
Gas Exchange ◽  
Low Temperature ◽  
Environmental Gradients ◽  
Gas Diffusion ◽  
Leaf Temperature ◽  
Heat Diffusion ◽  
Diffusion Resistance ◽  
Leaf Trichomes ◽  
Gas Fluxes ◽  
Gas Exchange Characteristics

Dense leaf trichomes can directly decrease gas fluxes through increased gas diffusion resistance and indirectly increase gas fluxes through increased leaf temperature due to increased heat diffusion resistance, which may contribute to adaptation to dry and/or low‐temperature conditions. However, it remains unclear whether the leaf‐trichome resistance increases or decreases the gas‐exchange rates through combined direct and indirect effects. We focused on Metrosideros polymorpha, a dominant tree species inhabiting a large range of environmental gradients in the Hawaiian Islands, whose leaves have an enormous variation in trichome thickness on the lower surface. In five elevational sites, we measured leaf morphological and physiological traits including trichome thickness, gas‐exchange characteristics, and leaf temperature. The trichome thickness was largest in the coldest and driest site and thinnest at the wettest site. Leaf temperature was significantly increased with trichome thickness. With biophysical and physiological models, we show that leaf trichomes can increase the daily photosynthesis through increasing leaf temperature only in the cold alpine area. The daily water‐use efficiency can be lower with increasing leaf trichomes at any elevational sites. Therefore, in terms of diffusion resistance, the leaf trichomes of M. polymorpha can contribute to the adaptation to low‐temperature environments but not to dry environments.

Gas exchange characteristics and dry matter accumulation of soybean treated with Nod factors

2007 ◽  
Vol 164 (10) ◽  
pp. 1391-1393 ◽  
Author(s):  
Juan Jose Almaraz ◽  
Xiaomin Zhou ◽  
Alfred Souleimanov ◽  
Donald Smith
Keyword(s):  
Gas Exchange ◽  
Dry Matter ◽  
Dry Matter Accumulation ◽  
Nod Factors ◽  
Gas Exchange Characteristics

scholarly journals Role of Ferrous Sulfate (FeSO4) in Resistance to Cadmium Stress in Two Rice (Oryza sativa L.) Genotypes

Biomolecules ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1693
Author(s):  
Javaria Afzal ◽  
Muhammad Hamzah Saleem ◽  
Fatima Batool ◽  
Ali Mohamed Elyamine ◽  
Muhammad Shoaib Rana ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gas Exchange ◽  
Plant Growth ◽  
Photosynthetic Pigments ◽  
Ferrous Sulfate ◽  
Oryza Sativa L ◽  
Enzymatic Antioxidants ◽  
Cd Stress ◽  
Ultra Structure ◽  
Gas Exchange Characteristics

The impact of heavy metal, i.e., cadmium (Cd), on the growth, photosynthetic pigments, gas exchange characteristics, oxidative stress biomarkers, and antioxidants machinery (enzymatic and non-enzymatic antioxidants), ions uptake, organic acids exudation, and ultra-structure of membranous bounded organelles of two rice (Oryza sativa L.) genotypes (Shan 63 and Lu 9803) were investigated with and without the exogenous application of ferrous sulfate (FeSO4). Two O. sativa genotypes were grown under different levels of CdCl2 [0 (no Cd), 50 and 100 µM] and then treated with exogenously supplemented ferrous sulfate (FeSO4) [0 (no Fe), 50 and 100 µM] for 21 days. The results revealed that Cd stress significantly (p < 0.05) affected plant growth and biomass, photosynthetic pigments, gas exchange characteristics, affected antioxidant machinery, sugar contents, and ions uptake/accumulation, and destroy the ultra-structure of many membranous bounded organelles. The findings also showed that Cd toxicity induces oxidative stress biomarkers, i.e., malondialdehyde (MDA) contents, hydrogen peroxide (H2O2) initiation, and electrolyte leakage (%), which was also manifested by increasing the enzymatic antioxidants, i.e., superoxidase dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) and non-enzymatic antioxidant compounds (phenolics, flavonoids, ascorbic acid, and anthocyanin) and organic acids exudation pattern in both O. sativa genotypes. At the same time, the results also elucidated that the O. sativa genotypes Lu 9803 are more tolerant to Cd stress than Shan 63. Although, results also illustrated that the exogenous application of ferrous sulfate (FeSO4) also decreased Cd toxicity in both O. sativa genotypes by increasing antioxidant capacity and thus improved the plant growth and biomass, photosynthetic pigments, gas exchange characteristics, and decrease oxidative stress in the roots and shoots of O. sativa genotypes. Here, we conclude that the exogenous supplementation of FeSO4 under short-term exposure of Cd stress significantly improved plant growth and biomass, photosynthetic pigments, gas exchange characteristics, regulate antioxidant defense system, and essential nutrients uptake and maintained the ultra-structure of membranous bounded organelles in O. sativa genotypes.

scholarly journals LEAF GAS EXCHANGE CHARACTERISTICS OF FOUR PAPAYA GENOTYPES DURING DIFFERENT STAGES OF DEVELOPMENT

2001 ◽  
Vol 23 (3) ◽  
pp. 522-525 ◽  
Author(s):  
ELIEMAR CAMPOSTRINI ◽  
OSVALDO KIYOSHI YAMANISHI ◽  
CARLOS A. MARTINEZ
Keyword(s):  
Gas Exchange ◽  
Carica Papaya ◽  
Leaf Gas Exchange ◽  
Carbon Dioxide Concentration ◽  
Field Capacity ◽  
Experimental Period ◽  
Clay Loam ◽  
Clay Loam Soil ◽  
Loam Soil ◽  
Gas Exchange Characteristics

In this research, was used four papaya (Carica papaya L.) genotypes: three from the 'Solo ( Sunrise Solo TJ, Sunrise Solo 72/12 and Baixinho de Santa Amália) group and one from the 'Formosa' group (Know-You 01). They were grown in plastic pots containing a sandy-clay-loam soil subjected to pH correction and fertilization, under greenhouse conditions. Throughout the experimental period plants were subjected to periodic irrigation to maintain the soil humitidy around field capacity. The experiment was conducted 73 days after sowing. In all genotypes, leaf gas exchange characteristics were determined. The net photosynthetic rate (A, mumol m-2 s-1 ), stomatal conductance (g s mol m-2 s-1), leaf temperature (T I, 0C) and intercellular carbon dioxide concentration (ci, muL L-1) on the 4th, 5th, 6th, 7th, 8th and 9th leaves from the plant apex were determined. No significant differences were observed for A, g s, c i, or Tl either among the leaves sampled from any of the genotypes. A was positively correlated with g s and in the other hand T I and g s were negatively correlated. The results suggest that, for 73 DAP, all the sampled papaya leaves functioned as sources of organs.

scholarly journals Kinetic bottlenecks to chemical exchange rates for deep-sea animals II: Carbon dioxide

2012 ◽  
Vol 9 (11) ◽  
pp. 15787-15821 ◽  
Author(s):  
A. F. Hofmann ◽  
E. T. Peltzer ◽  
P. G. Brewer
Keyword(s):  
Boundary Layer ◽  
Gas Exchange ◽  
Chemical Exchange ◽  
Co2 Concentration ◽  
Base System ◽  
Co2 Efflux ◽  
Marine Animals ◽  
Bulk Fluid ◽  
Marine Life ◽  
Fluid Properties

Abstract. Increased ocean acidification from fossil fuel CO2 invasion, from temperature-driven changes in respiration, and from possible leakage from sub-seabed geologic CO2 disposal has aroused concern over the impacts of elevated CO2 concentrations on marine life. Discussion of these impacts has so far focused only on changes in the oceanic bulk fluid properties (ΔpH, Δ[∑CO2] etc.) as the critical variable and with a major focus on carbonate shell dissolution. Here we describe the rate problem for animals that must export CO2 at about the same rate at which O2 is consumed. We analyze the basic properties controlling CO2 export within the diffusive boundary layer around marine animals in an ocean changing in temperature (T) and CO2 concentration in order to compare the challenges posed by O2 uptake under stress with the equivalent problem of CO2 expulsion. The problem is more complex than that for a non-reactive gas since, as with gas exchange of CO2 at the air-sea interface, the influence of the ensemble of reactions within the CO2-HCO3–-CO32– acid-base system needs to be considered. These reactions significantly facilitate CO2 efflux compared to O2 intake at equal temperature, pressure and flow rate under typical oceanic concentrations.The effect of these reactions can be described by an enhancement factor. For organisms, this means mechanically increasing flow over their surface to thin the boundary layer as is required to alleviate O2 stress seems not necessary to facilitate CO2 efflux. Nevertheless the elevated pCO2 cost most likely is non-zero. Regionally as with O2 the combination of T, P, and pH/pCO2 creates a zone of maximum CO2 stress at around 1000 m depth. But the net result is that, for the problem of gas exchange with the bulk ocean, the combination of an increasing T combined with declining O2 poses a greater challenge to marine life than does increasing CO2. The relationships developed here allow a more accurate prediction of the impacts on marine life from the combined effects of changing T, O2, and CO2 than can be estimated from single variable studies.

scholarly journals Effects of Day Length on Gas Exchange Characteristics in Crassulacean Acid Metabolism Plant, Dendrobium Ekapol cv. Panda.

1995 ◽  
Vol 64 (2) ◽  
pp. 201-208 ◽  
Author(s):  
Fumiaki SEKIZUKA ◽  
Akihiro NOSE ◽  
Yoshinobu KAWAMITSU ◽  
Seiichi MURAYAMA ◽  
Ken-ichi ARISUMI
Keyword(s):  
Gas Exchange ◽  
Crassulacean Acid Metabolism ◽  
Acid Metabolism ◽  
Day Length ◽  
Crassulacean Acid Metabolism Plant ◽  
Gas Exchange Characteristics
Sign in / Sign up

Export Citation Format

Share Document