scholarly journals Effects of Combined CO2 and O3 Exposures on Net CO2 Assimilation and Biomass Allocation in Seedlings of the Late-Successional Fagus Crenata

Climate ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 117 ◽  
Author(s):  
Tobita ◽  
Komatsu ◽  
Harayama ◽  
Yazaki ◽  
Kitaoka ◽  
...  
Keyword(s):  
Elevated Co2 ◽  
Biomass Allocation ◽  
Plant Biomass ◽  
Leaf Age ◽  
Ambient Air ◽  
Co2 Assimilation ◽  
Fagus Crenata ◽  
Elevated O3 ◽  
Net Co2 Assimilation ◽  
Elevated Co2 And O3

We examined the effects of elevated CO2 and elevated O3 concentrations on net CO2 assimilation and growth of Fagus crenata in a screen-aided free-air concentration-enrichment (FACE) system. Seedlings were exposed to ambient air (control), elevated CO2 (550 µmol mol−1 CO2, +CO2), elevated O3 (double the control, +O3), and the combination of elevated CO2 and O3 (+CO2+O3) for two growing seasons. The responses in light-saturated net CO2 assimilation rates per leaf area (Agrowth-CO2) at each ambient CO2 concentration to the elevated CO2 and/or O3 treatments varied widely with leaf age. In older leaves, Agrowth-CO2 was lower in the presence of +O3 than in untreated controls, but +CO2+O3 treatment had no effect on Agrowth-CO2 compared with the +CO2 treatment. Total plant biomass increased under conditions of elevated CO2 and was largest in the +CO2+O3 treatment. Biomass allocation to roots decreased with elevated CO2 and with elevated O3. Elongation of second-flush shoots also increased in the presence of elevated CO2 and was largest in the +CO2+O3 treatment. Collectively, these results suggest that conditions of elevated CO2 and O3 contribute to enhanced plant growth; reflecting changes in biomass allocation and mitigation of the negative impacts of O3 on net CO2 assimilation.

Net CO2 assimilation of taro and cocoyam as affected by shading and leaf age

1987 ◽  
Vol 11 (3) ◽  
pp. 245-251 ◽  
Author(s):  
Bruce Schaffer ◽  
Stephen K. O'Hair
Keyword(s):  
Leaf Age ◽  
Co2 Assimilation ◽  
Net Co2 Assimilation

scholarly journals Morphological and physiological responses of açaí seedlings subjected to different watering regimes

2016 ◽  
Vol 20 (4) ◽  
pp. 364-371 ◽  
Author(s):  
Walter V. D. Silvestre ◽  
Hugo A. Pinheiro ◽  
Rodrigo O. R. de M. Souza ◽  
Lenilson F. Palheta
Keyword(s):  
Plant Material ◽  
Plant Biomass ◽  
Field Capacity ◽  
Co2 Assimilation ◽  
Water Requirement ◽  
Higher Plant ◽  
Root Shoot Ratio ◽  
Net Co2 Assimilation ◽  
Total Plant Biomass ◽  
Total Plant

ABSTRACT Seedlings of açaí obtained from plant material native to floodplains (from Laranjeira and Muaná) and adapted to upland areas (cv. BRS-Pará and ecotype Hideo) were cultivated between March and October 2013 in a greenhouse, to test the hypothesis that water requirement for seedling production varies according to the origin of plant material. The seedlings were subjected to watering regimes corresponding to 40, 70, 100 and 130% of field capacity. Regardless of plant material, the production of vigorous seedlings was feasible only under irrigation of 100 and 130% of field capacity. The seedlings produced under 130% of field capacity showed higher plant height, stem diameter, number of leaves, total leaf area, leaf and root biomass, total plant biomass and root/shoot ratio than those produced under 100% of field capacity. The former also showed higher net CO2 assimilation rate, lower stomatal conductance and transpiration and higher instantaneous water use efficiency. In conclusion, the water requirement to produce vigorous seedlings of açaí does not vary within plant material and more vigorous seedlings are produced under irrigation of 130% of field capacity.

scholarly journals Growth and Photosynthetic Responses of Seedlings of Japanese White Birch, a Fast-Growing Pioneer Species, to Free-Air Elevated O3 and CO2

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 675
Author(s):  
Mitsutoshi Kitao ◽  
Evgenios Agathokleous ◽  
Kenichi Yazaki ◽  
Masabumi Komatsu ◽  
Satoshi Kitaoka ◽  
...  
Keyword(s):  
Light Intensity ◽  
Elevated Co2 ◽  
Biomass Allocation ◽  
Photosynthetic Acclimation ◽  
Total Biomass ◽  
White Birch ◽  
Elevated O3 ◽  
Free Air ◽  
Young Leaves ◽  
Photosynthetic Responses

Plant growth is not solely determined by the net photosynthetic rate (A), but also influenced by the amount of leaves as a photosynthetic apparatus. To evaluate growth responses to CO2 and O3, we investigated the effects of elevated CO2 (550–560 µmol mol−1) and O3 (52 nmol mol−1; 1.7 × ambient O3) on photosynthesis and biomass allocation in seedlings of Japanese white birch (Betula platyphylla var. japonica) grown in a free-air CO2 and O3 exposure system without any limitation of root growth. Total biomass was enhanced by elevated CO2 but decreased by elevated O3. The ratio of root to shoot (R:S ratio) showed no difference among the treatment combinations, suggesting that neither elevated CO2 nor elevated O3 affected biomass allocation in the leaf. Accordingly, photosynthetic responses to CO2 and O3 might be more important for the growth response of Japanese white birch. Based on A measured under respective growth CO2 conditions, light-saturated A at a light intensity of 1500 µmol m−2 s−1 (A1500) in young leaves (ca. 30 days old) exhibited no enhancement by elevated CO2 in August, suggesting photosynthetic acclimation to elevated CO2. However, lower A1500 was observed in old leaves (ca. 60 days old) of plants grown under elevated O3 (regulated to be twice ambient O3). Conversely, light-limited A measured under a light intensity of 200 µmol m−2 s−1 (A200) was significantly enhanced by elevated CO2 in young leaves, but suppressed by elevated O3 in old leaves. Decreases in total biomass under elevated O3 might be attributed to accelerated leaf senescence by O3, indicated by the reduced A1500 and A200 in old leaves. Increases in total biomass under elevated CO2 might be attributed to enhanced A under high light intensities, which possibly occurred before the photosynthetic acclimation observed in August, and/or enhanced A under limiting light intensities.

Effect of elevated carbon dioxide concentration at night on the growth and gas exchange of selected C4 species

1999 ◽  
Vol 26 (1) ◽  
pp. 71 ◽  
Author(s):  
Lewis H. Ziska ◽  
James A. Bunce
Keyword(s):  
Carbon Dioxide ◽  
Water Potential ◽  
Elevated Co2 ◽  
Leaf Water Potential ◽  
Plant Biomass ◽  
Co2 Assimilation ◽  
Leaf Water ◽  
Night Time ◽  
C4 Species ◽  
Co2 Concentrations

Biomass of certain C4 species is increased when plants are grown at elevated CO2 concentrations. Experiments using four C4 species (Amaranthus retroflexus L., Amaranthus hypochondriacus L., Sorghum bicolor (L.) Moench and Zea mays L.) exposed both day and night from sowing to carbon dioxide concentrations of 370 (ambient) or 700 µmol mol-1 (elevated) or to 370 µmol mol-1 during the day and 700 µmol mol-1 at night, determined whether any biomass increase at elevated CO2 concentrations was related to a reduction in the night-time rate of CO2 efflux at high night-time CO2 concentrations. Of the four species tested, only A. retroflexus significantly increased both CO2 assimilation (+13%) and plant biomass (+21%) at continuous elevated relative to continuous ambient concentrations of CO2. This increase was not associated with improvement in leaf water potential during dark or light periods. In contrast, high CO2 only during the night significantly reduced plant biomass compared to the 24 h ambient CO2 treatment for both A. retroflexus and Z. mays. This indicates that the observed increase in biomass at elevated CO2 for A. retroflexus was not caused by a reduction of carbon loss at night (i.e. increased carbon conservation), but rather a direct stimulation of daytime CO2 assimilation, independent of any improvement in leaf water potential.

Nitrogen supply in combination of nitrate and ammonium enhances harnessing of elevated atmospheric CO2 through improved nitrogen and carbon metabolism in wheat (Triticum aestivum)

2020 ◽  
Vol 71 (2) ◽  
pp. 101
Author(s):  
Muhammad Asif ◽  
Seray Zora ◽  
Yasemin Ceylan ◽  
Raheela Rehman ◽  
Levent Ozturk
Keyword(s):  
Triticum Aestivum ◽  
Biomass Production ◽  
Plant Biomass ◽  
Triticum Aestivum L ◽  
Co2 Assimilation ◽  
Elevated Atmospheric Co2 ◽  
N Supply ◽  
Photoassimilate Translocation ◽  
Net Co2 Assimilation ◽  
N Metabolism

Elevated carbon dioxide (e-CO2) levels from ambient (a-CO2) enhance plant biomass production and yield. However, this response is highly dependent on the availability and possibly the form of nitrogen (N) supply to plants. This study aimed to investigate changes in C and N metabolism of wheat (Triticum aestivum L.) in response to e-CO2 and N source. e-CO2 enhanced net CO2 assimilation but at highly variable rates depending on the form of N supply. Under e-CO2, net CO2 assimilation rate was in the order NO3– > NH4NO3 > NH4+ > urea. Plants supplied with ammonium and nitrate (i.e. NH4NO3) performed better in terms of biomass production and expressed a higher biomass enhancement ratio by e-CO2 than plants receiving sole applications of NO3–, NH4+ or urea. Supply of NH4NO3 also resulted in lower intercellular CO2, higher photoassimilate translocation to roots and lower accumulation of free amino acids than other N forms, indicating a better exploitation of the e-CO2 environment. Our results conclude that major physiological pathways of photosynthesis and protein and carbohydrate metabolism are differentially influenced by e-CO2 depending on the source of N supply. A balanced supply of NO3– and NH4+ to plant roots is the key to harnessing e-CO2 while minimising its adverse effects on quality of the produce.

Effects of Elevated Carbon Dioxide and Ozone on Foliar Flavonoids of Ginkgo biloba

2010 ◽  
Vol 113-116 ◽  
pp. 165-169 ◽  
Author(s):  
Wei Huang ◽  
Xing Yuan He ◽  
Chang Bing Liu ◽  
De Wen Li
Keyword(s):  
Carbon Dioxide ◽  
Elevated Co2 ◽  
Ginkgo Biloba ◽  
Dry Mass ◽  
Elevated O3 ◽  
Leaf Dry Mass ◽  
Elevated Co2 And O3 ◽  
Ozone Stress ◽  
Old Trees ◽  
Ambient Co2

To investigate the effect of elevated CO2 and O3 on the accumulation of flavonoids in Ginkgo Biloba leaves, four-year-old trees were exposed in open-top chambers with ambient and twice ambient CO2 and O3 concentrations singly and in combination in 2006. The results show that elevated CO2 reduce the concentrations of keampferol aglycon (-10%), isorhamnetin aglycon (-15%). Elevated O3 reduce the concentrations of the isorhamnetin aglycon (-7%), but increase the concentration of quercetin aglycon (+6%). Under elevated CO2 and O3 in combination, O3-derived effects on flavonoids concentrations are changed by elevated CO2, which are similar to that under the elevated CO2 alone. In conclusion, the concentrations of flavonoids are influenced by the changes in leaf dry mass induced by elevated CO2 and elevated O3. Furthermore, some flavonoids may not respond as antioxidant under ozone stress in ginkgo leaves.

scholarly journals Foliar application of plant growth regulators to ‘Crimson Seedless’ grapevine influences leaf age

2020 ◽  
pp. 422-430
Author(s):  
Amanda Cristina Esteves Amaro ◽  
Essione Ribeiro Souza ◽  
Laíse Sousa Santos ◽  
Daniel Baron ◽  
Elizabeth Orika Ono ◽  
...  
Keyword(s):  
Foliar Application ◽  
Block Design ◽  
Leaf Age ◽  
Co2 Assimilation ◽  
Fruit Production ◽  
Average Mass ◽  
Randomized Block Design ◽  
Net Co2 Assimilation ◽  
Acidity Level ◽  
Semiarid Conditions

We hypothesized that phytohormones and essential mineral nutrients influence the duration of leaf photosynthetic activity, fruit production and quality. We used a randomized block design, with four treatments and six replicates. Two commercial products were studied: Stimulate® (Stim), which is composed of a mixture of 0.009% cytokinin [N6-furfuryladenine or kinetin (Kt)], 0.005% auxin [4-indole-3-butyric acid (IBA)], and 0.005% gibberellin [gibberellic acid (GA3)], and Hold® (CoMo), which is composed of 2% cobalt and 3% molybdenum. These products were applied alone or in combination at different concentrations as follows: T1 - control, T2 - 1.8 L ha-1 Stim, T3 - 1.8 L ha-1 Stim + 1.0 L ha-1 CoMo, and T4 - 1.8 L h-1 Stim + 1.5 L ha-1 CoMo. The treatments were applied via foliar spraying at three phases: the inflorescence primordial stage (19 days after pruning [DAP]), the point at which the berries were 6 to 8 mm in diameter (49 DAP), and the initiation of berry elongation (56 DAP). We revealed that in semiarid conditions, the grapevines were characterized by evergreen leaves (do not lose their leaves) that maintained their photosynthetic capacity throughout their lifecycles (133 days after sprouting). The application of Stim alone (T2) yielded the maximal net CO2 assimilation rates and increased the carboxylation efficiencies, which indicated that this treatment might improve the photosynthetic output. These effects led to increases in the average mass, total length and width of the clusters per plant and decreased acidity level. Thus, we recommend the application of T2 for grapevines.

scholarly journals Successive Harvests Modulate the Productive and Physiological Behavior of Three Genovese Pesto Basil Cultivars

Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 560
Author(s):  
Luigi Formisano ◽  
Michele Ciriello ◽  
Christophe El-Nakhel ◽  
Marios C. Kyriacou ◽  
Youssef Rouphael
Keyword(s):  
Dry Matter ◽  
Co2 Assimilation ◽  
Stomatal Resistance ◽  
Matter Content ◽  
Dry Matter Content ◽  
Technological Parameters ◽  
Net Co2 Assimilation ◽  
Dry Biomass ◽  
Crop Cycle ◽  
The Impact

In the Italian culinary tradition, young and tender leaves of Genovese basil (Ocimum basilicum L.) are used to prepare pesto sauce, a tasty condiment that attracts the interest of the food processing industry. Like other leafy or aromatic vegetables, basil is harvested more than once during the crop cycle to maximize yield. However, the mechanical stress induced by successive cuts can affect crucial parameters associated with pesto processing (leaf/stem ratio, stem diameter, and dry matter). Our research accordingly aimed to evaluate the impact of successive harvests on three field-grown Genovese basil cultivars (“Aroma 2”, “Eleonora” and “Italiano Classico”) in terms of production, physiological behavior, and technological parameters. Between the first and second harvest, marketable fresh yield and shoot dry biomass increased by 148.4% and 172.9%, respectively; by contrast, the leaf-to-stem ratio decreased by 22.5%, while the dry matter content was unchanged. The increased fresh yield and shoot dry biomass at the second harvest derived from improved photosynthetic efficiency, which enabled higher net CO2 assimilation, Fv/Fm and transpiration as well as reduced stomatal resistance. Our findings suggest that, under the Mediterranean environment, “Italiano Classico” carries superior productive performance and optimal technological characteristics in line with industrial requirements. These promising results warrant further investigation of the impact successive harvests may have on the qualitative components of high-yielding basil genotypes with respect to consumer expectations of the final product.

Sign in / Sign up

Export Citation Format

Share Document