Changes in biomass and root:shoot ratio of field-grown Canada thistle (Cirsium arvense), a noxious, invasive weed, with elevated CO2: implications for control with glyphosate

Weed Science ◽  
2004 ◽  
Vol 52 (4) ◽  
pp. 584-588 ◽  
Author(s):  
Lewis H. Ziska ◽  
Shaun Faulkner ◽  
John Lydon
Keyword(s):  
Carbon Dioxide ◽  
Root Biomass ◽  
Dilution Effect ◽  
Leaf Damage ◽  
Shoot Biomass ◽  
Canada Thistle ◽  
Invasive Weed ◽  
Subsequent Increase ◽  
Perennial Weeds ◽  
Significant Difference

Canada thistle was grown under field conditions in 2000 and 2003 at ambient and elevated (∼ 350 μmol mol−1above ambient) carbon dioxide [CO2] to assess how rising [CO2] alters growth, biomass allocation, and efficacy of the postemergent herbicide glyphosate. By the time of glyphosate application, approximately 2 mo after emergence, elevated CO2had resulted in significant increases in both root and shoot biomass. However, the relative positive effect of [CO2] was much larger for root, relative to shoot growth, during this period (2.5- to 3.3-fold vs. 1.2- to 1.4-fold, respectively) with a subsequent increase in root to shoot ratio. Glyphosate was applied at 2.24 kg ae ha−1in 2000 and 2003. Subjective classification of leaf damage in shoots after spraying indicated no significant difference in the extent of necrosis in aboveground tissue as a function of CO2concentration. After a 6-wk regrowth period, significant reductions in shoot and root biomass relative to unsprayed plots were observed under ambient [CO2]. However, the decrease in the ratio of sprayed to unsprayed biomass was significantly less at elevated relative to ambient [CO2] conditions for roots in both years, and no difference in shoot biomass was observed between sprayed and unsprayed plots for Canada thistle grown at elevated [CO2] in either year. The observed reduction in glyphosate efficacy at the enriched [CO2] treatment did not appear to be associated with differential herbicide uptake, suggesting that tolerance was simply a dilution effect, related to the large stimulation of root relative to shoot biomass at elevated [CO2]. Overall, the study indicates that carbon dioxide–induced increases in root biomass could make Canada thistle and other perennial weeds that reproduce asexually from belowground organs harder to control in a higher [CO2] world.

Effects of sclerophyllous shrub competition on root and shoot development and biomass partitioning of Douglas-fir seedlings

1993 ◽  
Vol 23 (7) ◽  
pp. 1415-1426 ◽  
Author(s):  
Steven D. Tesch ◽  
Ed J. Korpela ◽  
Stephen D. Hobbs
Keyword(s):  
Root Biomass ◽  
Douglas Fir ◽  
Diameter Ratio ◽  
Shoot Biomass ◽  
Morphological Development ◽  
Regression Analyses ◽  
Significant Difference ◽  
Below Ground ◽  
Root And Shoot Biomass ◽  
Over Time

Effects of sclerophyllous shrub sprout competition on the morphological development of 1 + 0 containerized Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings were monitored above- and below-ground for 5 years after planting. Seedlings were planted among dead shrub sprouts 0.25 m in height (treatment C1), stumps of mature shrubs slashed just before planting (treatment C2), and shrub sprouts 0.5 m in height (treatment C3). In treatments C2 and C3, stumps sprouted quickly and sprouts grew vigorously, whereas C1 seedlings grew initially without competition. Above- and below-ground growth were reduced substantially and similarly by increasing competition. Root and shoot biomass of C1 seedlings were approximately 9–10 times and 22–25 times larger than that of C2 and C3 seedlings, respectively. During the first growing season, root biomass of seedlings in all three treatments increased relatively more than did shoot biomass. This growth pattern was reversed during subsequent seasons, and over the 5-year period resulted in greater growth in shoot biomass than in root biomass. Both shoot/root and height/diameter ratios increased over time in C2 and C3 seedlings. In contrast, the shoot/root ratio increased and the height/diameter ratio decreased in C1 seedlings. Allometric regression analyses showed no significant difference in biomass allocation to shoot and root among treatments over time.

scholarly journals Growth Responses of Boreal Scots Pine, Norway Spruce and Silver Birch Seedlings to Simulated Climate Warming over Three Growing Seasons in a Controlled Field Experiment

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 943
Author(s):  
Katri Nissinen ◽  
Virpi Virjamo ◽  
Antti Kilpeläinen ◽  
Veli-Pekka Ikonen ◽  
Laura Pikkarainen ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Scots Pine ◽  
Root Biomass ◽  
Growing Season ◽  
Silver Birch ◽  
Shoot Biomass ◽  
Growth Responses ◽  
Growing Seasons ◽  
Simulated Climate ◽  
Shoot And Root Biomass

We studied the growth responses of boreal Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L. Karst.) and silver birch (Betula pendula Roth) seedlings to simulated climate warming of an average of 1.3 °C over the growing season in a controlled field experiment in central Finland. We had six replicate plots for elevated and ambient temperature for each tree species. The warming treatment lasted for the conifers for three growing seasons and for the birch two growing seasons. We measured the height and diameter growth of all the seedlings weekly during the growing season. The shoot and root biomass and their ratios were measured annually in one-third of seedlings harvested from each plot in autumn. After two growing seasons, the height, diameter and shoot biomass were 45%, 19% and 41% larger in silver birch seedlings under the warming treatment, but the root biomass was clearly less affected. After three growing seasons, the height, diameter, shoot and root biomass were under a warming treatment 39, 47, 189 and 113% greater in Scots pine, but the root:shoot ratio 29% lower, respectively. The corresponding responses of Norway spruce to warming were clearly smaller (e.g., shoot biomass 46% higher under a warming treatment). As a comparison, the relative response of height growth in silver birch was after two growing seasons equal to that measured in Scots pine after three growing seasons. Based on our findings, especially silver birch seedlings, but also Scots pine seedlings benefitted from warming, which should be taken into account in forest regeneration in the future.

Split face comparative study of microneedling with platelet rich plasma versus Fractional carbon dioxide laser with platelet rich plasma in treatment of atrophic post acne scars

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Mohamed Abd Elnaeem Sallam ◽  
Khaled El Zawahry ◽  
Abdul Rahman Muhammed Ali Mustafa
Keyword(s):  
Carbon Dioxide ◽  
Co2 Laser ◽  
Carbon Dioxide Laser ◽  
Platelet Rich Plasma ◽  
Fractional Co2 Laser ◽  
Acne Scars ◽  
Significant Difference ◽  
Before And After ◽  
The Face ◽  
Fractional Carbon Dioxide Laser

Abstract Background Acne scars, is a challenge for dermatologists, despite having multiple treatment modalities like microneedling, dermabrasion, Fractional CO2 Laser, dermal fillers, etc. However, monotherapy has been hardly satisfactory because of the polymorphism seen with the scars. Objective Comparison between microneedling with platelet rich plasma versus Fractional carbon dioxide laser with platelet rich plasma in treatment of atrophic post acne scars. Patients and methods This study was carried out in department of dermatology, venereology and andrology, in Kobry El-Kobba Military complex during the period (from September 2018 to July 2020 ) on 20 patients of both sexes aged from 20 to 60 years old presenting with Goodman and Baron Grade II, III, IV acne scars . Results The study revealed a statistically significant difference (p = 0.017) between Goodman and Baron scar grades on the right side of the face before and after treatment indicating that microneedling with platelet rich plasma was effective in improving acne scars. Also, there is a statistically significant difference (p = 0.010) between Goodman and Baron scar grades on the left side of the face before and after treatment, indicating that fractional CO2 laser with platelet rich plasma was effective in improving acne scars. Conclusion and recommendation Further controlled and randomized studies are needed to validate our findings in a larger cohort of patients and longer follow up. Also, number of sessions might be more than 3 sessions.

scholarly journals Effects of Arbuscular Mycorrhizal Fungal Inoculation on Growth and Yield of Two Sweet Potato Varieties

2019 ◽  
pp. 1-8 ◽  
Author(s):  
Michael Ajanja Sakha ◽  
Joyce Jefwa ◽  
Joseph P. Gweyi-Onyango
Keyword(s):  
Sweet Potato ◽  
Arbuscular Mycorrhizal ◽  
Growth And Yield ◽  
Shoot Biomass ◽  
Storage Roots ◽  
Sweet Potatoes ◽  
Potato Varieties ◽  
Significant Difference ◽  
Amf Inoculation ◽  
Number Of Branches

Arbuscular mycorrhizal fungi (AMF) represent a functionally important component of soil microbial community, being of particular significance for plant mineral nutrition in tropical agro ecosystems. The effects of AMF inoculation on growth and yield of two sweet potato varieties was studied during the short rains season of 2017/2018 in the Teaching and Research Farm of Agricultural Science and Technology Department, Kenyatta University. The experiment was laid down as 2x2 factorial design in a randomized complete block design (RCBD) with three replications. The experimental factors were two sweet potato varieties (Kemb-10 and Bungoma) and AMF inoculum (With and without inoculation). Data on growth parameters was collected on vine length and number of branches, while data on yield was collected on marketable storage roots and shoot biomass. Data was analyzed using Genstat 15th edition and the results showed that there was significantly difference at P≤0.05 among the treatments. AMF inoculation increased growth and yield of sweet potatoes by vine length 29.74%, Number of branches 22.36%, marketable storage roots 18.32%, and shoot biomass 28.68% in week 20. Also, variety interacting with AMF inoculation enhanced growth and yield parameters. In conclusion, the study demonstrated that the application of commercial AMF inoculum solely or when interacting with varieties enhanced growth and yield of sweet potatoes, though there was no significant difference between the two varieties.

scholarly journals Early root development of Eucalyptus pellita F. Muell. seedlings from seed and stem cutting at nursery stage

2020 ◽  
Author(s):  
Affendy Hassan ◽  
Parveena Balachandran ◽  
Khairiyyah Razanah Khamis
Keyword(s):  
Root Development ◽  
Root Length ◽  
Root Biomass ◽  
Nitrogen Concentration ◽  
Stem Cutting ◽  
Shoot Biomass ◽  
Forest Plantation ◽  
Plant Materials ◽  
Eucalyptus Pellita ◽  
Root Intensity

Abstract BackgroundEucalyptus is among the important fast-growing species, and is typically managed on short rotation to sustain the production of timber, pulpwood, charcoal, and fire-wood. Macro-propagation using cutting for larger multiplying seedlings is cheaper and efficient instead of clonal seeds for uniform plant material seedling production. However, information on root growth of Eucalyptus pellita at early development from seed and stem cutting of E. pellita seedlings is still lacking. This is probably due to the difficulty in investigation belowground, and also due to methodological problems. With such information, it is useful for forest plantation company management in enhancing the understanding on strategies to optimize yield production with the appropriate agronomic or silvicultural approach in the field planting. Therefore, the objectives of this study were; to compare the root development of two different propagation seedlings of E. pellita; and to study the effect of various nitrogen concentration levels on two types of propagation of E. pellita seedlings. ResultsThe study was conducted using E. pellita seedlings from two types of propagation, namely, seed and stem cuttings, along with three different nitrogen concentrations (0, 50, and 200 kg N ha-1). Shoot biomass, root intensity (RI), total root intensity (TRI), root biomass, root length density (RLD), and specific root length (SRL) were recorded. Dried shoot biomass, RLD and SRL of E. pellita seedlings using stem cutting were significantly higher (P<0.05) compared to seed. Whereas, there were no significant differences (P>0.05) for root biomass, TRI and RI between the propagation types of E. pellita seedlings. Conclusions:E. pellita seedlings from stem cutting was greater in terms of root distribution compared to propagation by seeds at the nursery stage, and 50 kg N ha-1 was the optimal nitrogen concentration level from the considered levels to be applied to the E. pellita seedlings. The present study therefore provides more information and understanding on E. pellita for forest plantation companies in producing plant materials using stem cutting in a cost-effective and efficient manner. This would help the forest plantation companies in planning appropriate agronomic management in the future.

The effect of a ketamine constant rate infusion on cardiovascular variables in sheep anesthetized at the minimum alveolar concentration of sevoflurane that blunts adrenergic responses

2022 ◽  
pp. 1-7
Author(s):  
Kevin Chang ◽  
Michele Barletta ◽  
Kristen M. Messenger ◽  
Daniel M. Sakai ◽  
Rachel A. Reed ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Minimum Alveolar Concentration ◽  
Plasma Concentrations ◽  
Face Mask ◽  
Constant Rate Infusion ◽  
Carbon Dioxide Rebreathing ◽  
Constant Rate ◽  
Significant Difference ◽  
Treatment Administration ◽  
Rate Infusion

Abstract OBJECTIVE To evaluate the effect of a constant rate infusion of ketamine on cardiac index (CI) in sheep, as estimated using noninvasive cardiac output (NICO) monitoring by partial carbon dioxide rebreathing, when anesthetized with sevoflurane at the previously determined minimum alveolar concentration that blunts adrenergic responses (MACBAR). ANIMALS 12 healthy Dorset-crossbred adult sheep. PROCEDURES Sheep were anesthetized 2 times in a balanced placebo-controlled crossover design. Anesthesia was induced with sevoflurane delivered via a tight-fitting face mask and maintained at MACBAR. Following induction, sheep received either ketamine (1.5 mg/kg IV, followed by a constant rate infusion of 1.5 mg/kg/h) or an equivalent volume of saline (0.9% NaCl) solution (placebo). After an 8-day washout period, each sheep received the alternate treatment. NICO measurements were performed in triplicate 20 minutes after treatment administration and were converted to CI. Blood samples were collected prior to the start of NICO measurements for analysis of ketamine plasma concentrations. The paired t test was used to compare CI values between groups and the ketamine plasma concentrations with those achieved during the previous study. RESULTS Mean ± SD CI of the ketamine and placebo treatments were 2.69 ± 0.65 and 2.57 ± 0.53 L/min/m2, respectively. No significant difference was found between the 2 treatments. Mean ketamine plasma concentration achieved prior to the NICO measurement was 1.37 ± 0.58 µg/mL, with no significant difference observed between the current and prior study. CLINICAL RELEVANCE Ketamine, at the dose administered, did not significantly increase the CI in sheep when determined by partial carbon dioxide rebreathing.

Feasıbılıty of Transcutaneous Method for Carbon Dıoxıde Monıtorıng in an Intensive Care Unıt

2022 ◽  
Vol 18 ◽  
Author(s):  
Nazlıhan Boyacı ◽  
Sariyya Mammadova ◽  
Nurgül Naurizbay ◽  
Merve Güleryüz ◽  
Kamil İnci ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Intensive Care Unit ◽  
Intensive Care ◽  
Partial Pressure ◽  
Blood Gas ◽  
Peripheral Oxygen Saturation ◽  
Arterial Blood Gas ◽  
Arterial Blood ◽  
Randomized Controlled Studies ◽  
Significant Difference

Background: Transcutaneous partial pressure of carbon dioxide (PtCO2) monitorization provides a continuous and non-invasive measurement of partial pressure of carbon dioxide (pCO2). In addition, peripheral oxygen saturation (SpO2) can also be measured and followed by this method. However, data regarding the correlation between PtCO2 and arterial pCO2 (PaCO2) measurements acquired from peripheric arterial blood gas is controversial. Objective: We aimed to determine the reliability of PtCO2 with PaCO2 based on its advantages, like non-invasiveness and continuous applicability. Methods: Thirty-five adult patients with hypercapnic respiratory failure admitted to our tertiary medical intensive care unit (ICU) were included. Then we compared PtCO2 and PaCO2 and both SpO2 measurements simultaneously. Thirty measurements from the deltoid zone and 26 measurements from the cheek zone were applied. Results: PtCO2 could not be measured from the deltoid region in 5 (14%) patients. SpO2 and pulse rate could not be detected at 8 (26.7%) of the deltoid zone measurements. Correlation coefficients between PtCO2 and PaCO2 from deltoid and the cheek region were r: 0,915 and r: 0,946 (p = 0,0001). In comparison with the Bland-Altman test, difference in deltoid measurements was -1,38 ± 1,18 mmHg (p = 0.252) and in cheek measurements it was -5,12 ± 0,92 mmHg (p = 0,0001). There was no statistically significant difference between SpO2 measurements in each region. Conclusion: Our results suggest that PtCO2 and SpO2 measurements from the deltoid region are reliable compared to the arterial blood gas analysis in hypercapnic ICU patients. More randomized controlled studies investigating the effects of different measurement areas, hemodynamic parameters, and hemoglobin levels are needed.

Herbage biomass and its relationship to soil carbon under long-term grazing in northern temperate grasslands

2019 ◽  
Vol 99 (6) ◽  
pp. 905-916
Author(s):  
E.W. Bork ◽  
M.P. Lyseng ◽  
D.B. Hewins ◽  
C.N. Carlyle ◽  
S.X. Chang ◽  
...  
Keyword(s):  
Soil Carbon ◽  
Root Biomass ◽  
Mineral Soil ◽  
Belowground Biomass ◽  
Cattle Grazing ◽  
Shoot Biomass ◽  
Positive Contribution ◽  
Temperate Grasslands ◽  
Soil C

While northern temperate grasslands are important for supporting beef production, it remains unclear how grassland above- and belowground biomass responds to long-term cattle grazing. Here, we use a comprehensive dataset from 73 grasslands distributed across a broad agro-climatic gradient to quantify grassland shoot, litter, and shallow (top 30 cm) root biomass in areas with and without grazing. Additionally, we relate biomass to soil carbon (C) concentrations. Forb biomass was greater (p < 0.05) in grazed areas, particularly those receiving more rainfall. In contrast, grass and total aboveground herbage biomass did not differ with grazing (total: 2320 kg ha−1 for grazed vs. 2210 kg ha−1 for non-grazed; p > 0.05). Forb crude protein concentrations were lower (p < 0.05) in grazed communities compared with those that were non-grazed. Grasslands subjected to grazing had 56% less litter mass. Root biomass down to 30 cm remained similar between areas with (9090 kg ha−1) and without (7130 kg ha−1) grazing (p > 0.05). Surface mineral soil C concentrations were positively related to peak grassland biomass, particularly total (above + belowground) biomass, and with increasing forb biomass in grazed areas. Finally, total aboveground shoot biomass and soil C concentrations in the top 15 cm of soil were both positively related to the proportion of introduced plant diversity in grazed and non-grazed grasslands. Overall, cattle grazing at moderate stocking rates had minimal impact on peak grassland biomass, including above- and belowground, and a positive contribution exists from introduced plant species to maintaining herbage productivity and soil C.

scholarly journals Comparisons of the Nonlinear Relationship of Cerebral Blood Flow Response and Cerebral Vasomotor Reactivity to Carbon Dioxide under Hyperventilation between Postural Orthostatic Tachycardia Syndrome Patients and Healthy Subjects

2020 ◽  
Vol 9 (12) ◽  
pp. 4088
Author(s):  
Shyan-Lung Lin ◽  
Shoou-Jeng Yeh ◽  
Ching-Kun Chen ◽  
Yu-Liang Hsu ◽  
Chih-En Kuo ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Blood Flow Velocity ◽  
Cerebral Blood Flow Velocity ◽  
Postural Orthostatic Tachycardia Syndrome ◽  
Significant Difference ◽  
Cerebral Vasomotor Reactivity ◽  
End Tidal ◽  
Fitting Model

Postural orthostatic tachycardia syndrome (POTS) typically occurs in youths, and early accurate POTS diagnosis is challenging. A recent hypothesis suggests that upright cognitive impairment in POTS occurs because reduced cerebral blood flow velocity (CBFV) and cerebrovascular response to carbon dioxide (CO2) are nonlinear during transient changes in end-tidal CO2 (PETCO2). This novel study aimed to reveal the interaction between cerebral autoregulation and ventilatory control in POTS patients by using tilt table and hyperventilation to alter the CO2 tension between 10 and 30 mmHg. The cerebral blood flow velocity (CBFV), partial pressure of end-tidal carbon dioxide (PETCO2), and other cardiopulmonary signals were recorded for POTS patients and two healthy groups including those aged >45 years (Healthy-Elder) and aged <45 years (Healthy-Youth) throughout the experiment. Two nonlinear regression functions, Models I and II, were applied to evaluate their CBFV-PETCO2 relationship and cerebral vasomotor reactivity (CVMR). Among the estimated parameters, the curve-fitting Model I for CBFV and CVMR responses to CO2 for POTS patients demonstrated an observable dissimilarity in CBFVmax (p = 0.011), mid-PETCO2 (p = 0.013), and PETCO2 range (p = 0.023) compared with those of Healthy-Youth and in CBFVmax (p = 0.015) and CVMRmax compared with those of Healthy-Elder. With curve-fitting Model II for POTS patients, the fit parameters of curvilinear (p = 0.036) and PETCO2 level (p = 0.033) displayed significant difference in comparison with Healthy-Youth parameters; range of change (p = 0.042), PETCO2 level, and CBFVmax also displayed a significant difference in comparison with Healthy-Elder parameters. The results of this study contribute toward developing an early accurate diagnosis of impaired CBFV responses to CO2 for POTS patients.

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