scholarly journals Factors Affecting Reductions in Photosynthesis Caused by Applying Horticultural Oil to Grapevine Leaves

HortScience ◽  
2006 ◽  
Vol 41 (2) ◽  
pp. 346-351 ◽  
Author(s):  
Anton Baudoin ◽  
Sarah Finger McDonald ◽  
Tony K. Wolf
Keyword(s):  
Leaf Surface ◽  
Net Photosynthesis ◽  
Soluble Solids ◽  
Retention Data ◽  
Foliar Injury ◽  
Visible Injury ◽  
Factors Affecting ◽  
Small Water ◽  
Significant Difference ◽  
Leaf Surfaces

Phytotoxicity of horticultural oil, applied shortly before antifungal sulfur, was evaluated for 23 grape cultivars. Oil application significantly reduced accumulation of soluble solids in berries of 9 of 23 cultivars, but there was no relationship with visible foliar injury. Treatment of leaves of Vitis labrusca `Catawba' with 1.5% JMS Stylet-Oil reduced leaf net photosynthesis (Pn) by 50% to 60% and of Vitis vinifera `Chardonnay' by 20% to 30% 1 day after application. Pn was reduced only when the lower (abaxial) leaf surface was treated; treatment of only the adaxial leaf surface had little effect. The Pn depression in `Catawba' persisted 3 to 4 weeks, whereas reductions in `Chardonnay' persisted less than 2 weeks. The Pn-depressing effect of oil was not significantly ameliorated by real or simulated rainfall, and washing the lower leaf surfaces with water and detergent also had only limited effect. There was no significant difference in Pn depression from oil applications made in the middle of the day (stomata open) compared to application in the evening (stomata closed), or from oil applied at higher versus lower application pressure. The greater sensitivity of `Catawba' than `Chardonnay' to Pn depression by oil may be related to the amount of oil retained by the leaves; the pubescent lower leaf surfaces of `Catawba' retained more than twice as much spray emulsion as did the more glabrous leaves of `Chardonnay'. Visible injury was mild in both cultivars, with small water-soaked lesions developing more commonly on `Chardonnay' than on `Catawba' leaves. Spray oil retention data for additional cultivars suggested that differences in retention can explain a portion of the differences in horticultural oil phytotoxicity.

Physiological Response of Rice (Oryza sativa) to Fenoxaprop

Weed Science ◽  
1990 ◽  
Vol 38 (6) ◽  
pp. 459-462 ◽  
Author(s):  
Derrick M. Oosterhuis ◽  
Stan D. Wullschleger ◽  
Ron E. Hampton ◽  
Rosalind A. Ball
Keyword(s):  
Direct Contact ◽  
Physiological Responses ◽  
Net Photosynthesis ◽  
Dry Weight ◽  
Rice Cultivars ◽  
Foliar Injury ◽  
Leaf Elongation ◽  
Visible Injury ◽  
Shoot Dry Weight ◽  
Spray Droplets

Growth chamber experiments were conducted to elucidate the morphological and physiological responses of rice to postemergence application of fenoxaprop. Two rice cultivars, ‘Newbonnet’ and ‘Mars’, and barnyardgrass were treated with 0.17 kg ai ha−1fenoxaprop at the five-leaf stage. Within 2 days of fenoxaprop application, rice cultivars developed a white chlorotic band across leaves that were in direct contact with spray droplets. Leaf elongation rates for the two rice cultivars were inhibited by 40% after 4 days and by over 50% after 14 days. Inhibition of leaf elongation by fenoxaprop contributed to an overall decrease in leaf area and shoot dry weight. Net photosynthesis was reduced by 35% in fenoxaprop-treated plants 11 days after application, although stomatal conductance was not affected. Nitrogen fertilization prior to fenoxaprop application increased foliar injury of both rice cultivars. Visible injury symptoms showed the following order of susceptibility to foliar-applied fenoxaprop: barnyardgrass > Mars rice > Newbonnet rice.

scholarly journals Quality of Different Papaya Cultivars Grown in the Greenhouse throughout the Year in Subtropical Regions

2021 ◽  
pp. 20-30
Author(s):  
Esma Güneş ◽  
Hatice Reyhan Öziyci ◽  
Hamide Gübbük
Keyword(s):  
Fruit Quality ◽  
Soluble Solids ◽  
Total Phenolic ◽  
Maturity Stage ◽  
Subtropical Climate ◽  
Factors Affecting ◽  
Significant Difference ◽  
Soft Fruit ◽  
Greenhouse Cultivation ◽  
The Impact

Harvest time is one of the factors affecting postharvest fruit quality. Under the subtropical condition, greenhouse cultivation allows a year-round harvest. However, the crop should meet the quality and the marketing criteria for overall customer satisfaction. This study aims to determine the impact of the harvest season on the quality characteristics of papaya fruit. For this purpose, two different cultivars (Sel-42 and Tainung) were grown in the greenhouse and harvested in the winter, the summer, the spring, and the autumn of two years. Sampling was carried out at the same visual maturity stage at each season. The two cultivars had soft fruit flesh almost throughout the year, although the fruit harvested in the winter had a better visual appeal in terms of color. Both fruit cultivars harvested in the autumn had higher soluble solids and lower acidity. The highest concentrations of total phenolic content and L-ascorbic acid were observed in the spring and summer season harvested fruits although there was no significant difference between those (P > 0.05). It was concluded that the growth in the greenhouse minimizes the harvest season effects on papaya fruit quality. Thus, greenhouse cultivation is recommended for a higher quality product, especially in a subtropical climate.

scholarly journals Screening Buddleia Cultivars for Acute Ozone Sensitivity

1997 ◽  
Vol 15 (3) ◽  
pp. 142-145
Author(s):  
Douglas A. Findley ◽  
Gary J. Keever ◽  
Arthur H. Chappelka ◽  
Charles H. Gilliam ◽  
D. Joseph Eakes
Keyword(s):  
Leaf Surface ◽  
Severity Index ◽  
Severe Injury ◽  
Foliar Injury ◽  
Visible Injury ◽  
Exposure Response ◽  
Ozone Sensitivity ◽  
Adaxial Leaf Surface

Abstract Eight cultivars of buddleia were exposed to ozone (O3) concentrations up to 375 ppb for two 4-hour periods on consecutive days in 1995. Visible injury to all cultivars consisted of small, discrete spots, reddish purple in color, on the adaxial leaf surface. Cultivars differed in sensitivity to acute O3 exposure with ‘Empire Blue’ and ‘Opera’ being the most tolerant and ‘Black Knight’, ‘Nanho Blue’, ‘Pink Delight’, and ‘Royal Red’ the most sensitive. Severe injury occurred on the most sensitive cultivars with O3 exposures of 250 or 375 ppb. At the highest O3 concentration, the severity index (SI), an indicator of foliar injury, ranged from 1.3 (less injury) for ‘Opera’ to 4.6 (more injury) for ‘Pink Delight’. An exposure-response study with ‘Black Knight’ resulted in visible injury increasing as both concentration and number of exposures increased, with the most severe injury to plants given the most exposures (5 days) to the highest concentration (375 ppb, SI of 6.3).

Factors affecting progression to permanent atrial fibrillation in an unselected population of patients with non-permanent form of atrial fibrillation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
V.L Malavasi ◽  
E Fantecchi ◽  
V Tordoni ◽  
L Melara ◽  
A Barbieri ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Cox Regression ◽  
Area Under The Curve ◽  
Roc Curves ◽  
Factors Affecting ◽  
Cox Proportional Hazard ◽  
Significant Difference ◽  
History Of ◽  
Unselected Population ◽  
Cox Proportional Hazard Regression

Abstract Background Natural history of atrial fibrillation (AF) shows a progression of arrhythmia from non-permanent to permanent AF. Permanent AF was found associated with a worse prognosis than non-permanent one. Aim To assess the factors associated with progression to permanent AF in an unselected population of AF patients with non-permanent AF. Methods In this prospective study we enrolled in- as well as out-patients with non-permanent AF and age ≥18 years, with at least one episode of ECG-documented AF within 1 year. The patients were followed-up at 1 month and every 6 months thereafter. Results Out of 523 patients, 314 (60%) were in non-permanent AF (80 [25.5%] paroxysmal AF, 165 [52.5%] persistent AF, 69 [2%] first diagnosed AF), mostly male (188, 59.9%), median age 71 years (IQ range 62–77), median CHA2DS2VASc 3 (1–4), median HATCH score 1 (1–2). After a median follow-up of 701 (IQ range 437–902) days, 66 patients (21%) showed permanent AF. CHA2DS2VASc and HATCH scores were incrementally associated to progression to permanent AF (CHA2DS2VASc χ2 p=0.001; HATCH χ2 p=0.017; p for trend CHA2DS2VASc <0.001, HATCH p=0.001). At multivariable Cox proportional hazard regression the following variables were significantly associated with AF progression: age (hazard ratio [HR] 1.041; 95% CI: 1.004–1.079; p=0.028), at least moderate left atrial (LA) enlargement (>42 ml/m2) (HR 2.092; 95% CI: 1.132–3.866; p=0.018), antiarrhythmics drugs after the enrollment (HR 0.087; 95% CI: 0.011–0.662; p=0.018), EHRA score >2 (HR 0.351; 95% CI: 0.158–0.779; p=0.010) and Valvular HD (HR 2.161; 95% CI: 1.057–4.420; p=0.035). Adding LA dilation to HATCH score (HATCH-LA) and assigning 2 points based on multivariable Cox regression, HATCH-LA was statistically better in ROC curves in prediction of AF progression vs HATCH score (area under the curve 0.695 vs 0.636; DeLong p=0.0225). Survival-free curves on freedom from permanent AF using as discriminator HATCH-LA score ≤2 vs >2 led to a statistically significant difference (χ2=16.080 p<0.001), but the same was not found for HATCH score (χ2 =3.099; p=0.078). Conclusions In patients without permanent AF, progression of AF was independentely related to age, LA dilation, AF symptoms severity, antiarrhythmic drugs and Valvular HD. HATCH score predicted AF progression and adding to it LA dilation (at least moderate) improved patients stratification for the risk of evolution to permanent AF. Funding Acknowledgement Type of funding source: None

scholarly journals Comparative Evaluation of Orthostatic Hypotension in Patients with Diabetic Nephropathy

2021 ◽  
pp. 1-7
Author(s):  
Gamze Aytaş ◽  
Rümeyza Kazancıoğlu ◽  
Ömer C. Elçioğlu ◽  
Meltem Gürsu ◽  
A. Serra Artan ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
Orthostatic Hypotension ◽  
Electronic Device ◽  
Channel Blockers ◽  
Factors Affecting ◽  
Clinical Criteria ◽  
Measure Blood Pressure ◽  
Significant Difference ◽  
Male Patients ◽  
Very High

<b><i>Introduction:</i></b> Orthostatic hypotension (OH) affects 5–20% of the population. Our study investigates the presence of OH in diabetic nephropathy (DNP) patients and the factors affecting OH in comparison with nondiabetic chronic kidney disease (NDCKD) patients. <b><i>Method:</i></b> Patients presented to the nephrology clinic, and those who consented were included in the study. DNP was defined by kidney biopsy and/or clinical criteria. NDCKD patients of the same sex, age, and eGFR were matched to DNP patients. Demographic parameters and medications were obtained from the records. OH was determined by Mayo clinic criteria. The same researcher used an electronic device to measure blood pressure (BP). All samples were taken and analyzed the same day for biochemical and hematologic parameters and albuminuria. <b><i>Results:</i></b> 112 (51 F, 61 M, mean age: 62.56 ± 9.35 years) DNP and 94 (40 F, 54 M, mean age: 62.23 ± 10.08 years) NDCKD patients were included. There was no significant difference between DNP and NDCKD groups in terms of OH prevalence (70.5 vs. 61.7%, <i>p</i> = 0.181). Male patients had significantly higher OH prevalence than female patients (74.7 vs. 60.0%, <i>p</i> = 0.026). There was no significant difference in change in systolic BP between the groups (24.00 [10.00–32.00] mm Hg vs. 24.00 [13.75–30.25] mm Hg, <i>p</i> = 0.797), but the change in diastolic BP was significantly higher in the DNP group (8.00 [2.00–13.00] mm Hg vs. 6.00 [2.00–9.00] mm Hg, <i>p</i> = 0.025). In the DNP group, patients with OH had significantly higher uric acid levels than those without OH (7.18 ± 1.55 vs. 6.36 ± 1.65 mg/dL, <i>p</i> = 0.017). And, 73.7% of patients on calcium channel blockers developed OH (<i>p</i> = 0.015), and OH developed in 80.6% of 36 patients on alpha-blockers (<i>p</i> = 0.049). <b><i>Conclusion:</i></b> OH prevalence is very high in CKD, and etiology of CKD does not have a statistically significant effect on the frequency of OH, despite a difference that could be meaningful clinically. Therefore, patients with CKD are checked for OH, with or without concurrent diabetes mellitus. Evaluation of postural BP changes should be a part of nephrology practice.

Calibration Transfer between Miniature Photodiode Array-Based Spectrometers in the near Infrared Assessment of Mandarin Soluble Solids Content

2002 ◽  
Vol 10 (1) ◽  
pp. 27-35 ◽  
Author(s):  
C.V. Greensill ◽  
K.B. Walsh
Keyword(s):  
Near Infrared ◽  
Model Updating ◽  
Soluble Solids ◽  
Soluble Solid Content ◽  
Calibration Model ◽  
Calibration Transfer ◽  
Orthogonal Signal Correction ◽  
Significant Difference ◽  
Photodiode Array ◽  
Direct Standardisation

The transfer of predictive models among photodiode array based, short wave near infrared spectrometers using the same illumination/detection optical geometry has been attempted using various chemometric techniques, including slope and bias correction (SBC), direct standardisation (DS), piecewise direct standardisation (PDS), double window PDS (DWPDS), orthogonal signal correction (OSC), finite impulse transform (FIR) and wavelet transform (WT). Additionally, an interpolation and photometric response correction method, a wavelength selection method and a model updating method were assessed. Calibration transfer was attempted across two populations of mandarin fruit. Model performance was compared in terms of root mean squared error of prediction ( RMSEP), using Fearn's significance testing, for calibration transfer (standardisation) between pairs of spectrometers from a group of four spectrometers. For example, when a calibration model (Root Mean Square Error of Cross-Validation [ RMSECV = 0.26% soluble solid content (SSC)], developed on one spectrometer, was used with spectral data collected on another spectrometer, a poor prediction resulted ( RMSEP = 2.5% SSC). A modified WT method performed significantly better (e.g. RMSEP = 0.25% SSC) than all other standardisation methods (10 of 12 cases), and almost on a par with model updating (MU) (nine cases with no significant difference, one case and two cases significantly better for WT and MU, respectively).

Floristic study and assessment of the environmental factors governing the distribution of riparian plants in the Zat sub-Basin: Tensift Watershed, Morocco

2020 ◽  
Vol 45 (2) ◽  
pp. 7900-7915
Author(s):  
Mostakim Lahcen ◽  
Fetnassi Nidal ◽  
Ghamizi Mohamed
Keyword(s):  
Environmental Factors ◽  
Pearson Correlation ◽  
Ecological Status ◽  
Environmental Parameters ◽  
Quality Parameters ◽  
Phosphorus Concentration ◽  
Factors Affecting ◽  
Riparian Plants ◽  
Emergent Plants ◽  
Significant Difference

Measuring the phytodiversity and determining environmental factors affecting the abundance and distribution of riparian plants of Zat sub-basin in Morocco were carried out in this study. A hypothesis was tested whether there is any statistically significant difference in environmental parameters and plants communities among the Zat River and its tributaries. For this purpose, water quality parameters such as temperature, pH, salinity, electrical conductivity, Dissolved Oxygen, nitrate and phosphorus concentration, and riparian plants diversity were estimated at 17 stations along the Zat River and its tributaries during the periods (2018 and 2019). The Canonical Correspondence Analysis (CCA) and Pearson correlation were preformed to assess the relationship between environmental parameters, and the distribution and abundance of riparian plants inventoried. The presence of 113 species was recorded, distributed between 43 families and 97 genera, 9 of which were floating-leaved, 24 submerged, and 80 emergent plants. The rare and threatened species inventoried were represented by 7 taxa, whereas 6 species are reported as endemic. Raunkiaer classification showed a dominance of therophytes (38.39%) over the other groups. According to CCA, the abiotic parameters (DO, elevation, salinity and nitrate concentration) were statistically significant parameters governing the distribution and abundance of the riparian plants inventoried. The results obtained reveal the state of the riparian vegetation in the Zat subBasin, therefore we can consider them as a reliable component for the assessment of the ecological status of the aquatic environment.

Particle size, leaf pubescence and condition of humidity at leaf surfaces are key factors determining the retention of volcanic ash on crop foliage.

2021 ◽  
Author(s):  
Noa Ligot ◽  
Benoît Pereira ◽  
Patrick Bogaert ◽  
Guillaume Lobet ◽  
Pierre Delmelle
Keyword(s):  
Particle Size ◽  
Surface Area ◽  
Leaf Surface ◽  
Volcanic Risk ◽  
Chilli Pepper ◽  
Leaf Pubescence ◽  
Leaf Surfaces ◽  
Plant Foliage ◽  
Leaf Surface Area ◽  
Ash Deposit

&lt;p&gt;Volcanic ashfall negatively affects crops, causing major economic losses and jeopardising the livelihood of farmers in developing countries where agriculture is at volcanic risk. Ash on plant foliage reduces the amount of incident light, thereby limiting photosynthesis and plant yield. An excessive ash load may also result in mechanical plant damages, such as defoliation and breakage of the stem and twigs. Characterising crop vulnerability to ashfall is critical to conduct a comprehensive volcanic risk analysis. This is normally done by describing the relationship between the ash deposit thickness and the corresponding reduction in crop yield, i.e. a fragility function. However, ash depth measured on the ground surface is a crude proxy of ash retention on plant foliage as this metrics neglects other factors, such as ash particle size, leaf pubescence and condition of humidity at leaf surfaces, which are likely to influence the amount of ash that stays on leaves.&lt;/p&gt;&lt;p&gt;Here we report the results of greenhouse experiments in which we measured the percentage of leaf surface area covered by ash particles for one hairy leaf plant (tomato, Solanum lycopersicum L.) and one hairless leaf plant (chilli pepper, Capsicum annuum L.) exposed to simulated ashfalls. We tested six particle size ranges (&amp;#8804; 90, 90-125, 125-250, 250-500, 500-1000, 1000-2000 &amp;#181;m) and two conditions of humidity at leaf surfaces, i.e. dry and wet. Each treatment consisted of 15 replicates. The tomato and chilli pepper plants exposed to ash were at the seven- and eight-leaf stage, respectively. An ash load of ~570 g m&lt;sup&gt;-2 &lt;/sup&gt;was applied to each plant using a homemade ashfall simulator. We estimated the leaf surface area covered by ash from pictures taken before and immediately after the simulated ashfall. The ImageJ software was used for image processing and analysis.&lt;/p&gt;&lt;p&gt;Our results show that leaf coverage by ash increases with decreasing particle size. Exposure of tomato and chilli pepper to ash &amp;#8804; 90 &amp;#956;m always led to ~90% coverage of the leaf surface area. For coarser particles sizes (i.e. between 125 and 500 &amp;#181;m) and dry condition at leaf surfaces, a significantly higher percentage (on average 29 and 16%) of the leaf surface area was covered by ash in the case of tomato compared to chilli pepper, highlighting the influence of leaf pubescence on ash retention. In addition, for particle sizes between 90 and 500 &amp;#181;m, wetting of the leaf surfaces prior to ashfall enhanced the ash cover by 19 &amp;#177; 5% and 34 &amp;#177; 11% for tomato and chilli pepper, respectively.&lt;/p&gt;&lt;p&gt;These findings highlight that ash deposit thickness alone cannot describe the hazard intensity accurately. A thin deposit of fine ash (&amp;#8804; 90 &amp;#181;m) will likely cover the entire leaf surface area, thereby eliciting a disproportionate effect on plant foliage compared to a thicker but coarser deposit. Similarly, for a same ash depth, leaf pubescence and humid conditions at the leaf surfaces will enhance ash retention, thereby increasing the likelihood of damage. Our study will contribute to improve the reliability of crop fragility functions used in volcanic risk assessment.&lt;/p&gt;

Determination Of Factors Affecting Father-Baby Attachment

2021 ◽  
Vol 6 (14) ◽  
pp. 1-7
Author(s):  
Emine Serap ÇAĞAN ◽  
Birsen KARACA SAYDAM ◽  
Sinem GÜLÜMSER ATEŞ ◽  
Rabia EKTİ GENÇ ◽  
Esin ÇEBER TURFAN
Keyword(s):  
Cross Sectional Study ◽  
Study Data ◽  
Cross Sectional ◽  
Infant Attachment ◽  
Factors Affecting ◽  
Attachment Figure ◽  
Gynecology And Obstetrics ◽  
Significant Difference ◽  
Package Program ◽  
The Difference

Introduction: The primary attachment figure is mostly defined as the mother, and studies focus on the mother. However, in many babies, basic attachment is just as good with the father as with the mother. It is seen that there are very few studies in the literature investigating the correlations of father-infant attachment relationships.. The aim of this study is to determine the father-infant attachment status and to determine the factors affecting attachment. Method: The population of the cross-sectional study consisted of the spouses of all puerperant women hospitalized in the Gynecology and Obstetrics Clinic between September 1, 2018 and October 1, 2018. The sample size consisted of 156 fathers who agreed to participate in the study. Father identification form and father-infant attachment scale were used to collect the study data. The analysis of the data obtained from the research was carried out on the computer using the SPSS 16.0 package program. Results: 156 fathers participated in the study. The mean age of the fathers is 33.64±6.49, and 38.5% of them have a bachelor's degree. 91.0% of fathers stated that they felt ready for fatherhood. The fathers' Father-Infant Attachment Scale mean score was 82.60±7.72 In the analysis, the difference between the variables and the total score of the scale was found to be statistically insignificant (p>0.05). Discussion and Conclusion: At the end of the study, the bonding process of fathers participating in the study with their babies and the factors affecting this process were evaluated and it was seen that the father-infant attachment scale mean scores of the fathers participating in the study were high and were similar to other studies. In addition, when the basic factors affecting father-infant attachment were compared with the attachment scale mean score, it was found that there was no statistically significant difference.

Lack of Internalization of Escherichia coli O157:H7 in Lettuce (Lactuca sativa L.) after Leaf Surface and Soil Inoculation

2009 ◽  
Vol 72 (10) ◽  
pp. 2028-2037 ◽  
Author(s):  
GUODONG ZHANG ◽  
LI MA ◽  
LARRY R. BEUCHAT ◽  
MARILYN C. ERICKSON ◽  
VANESSA H. PHELAN ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Leaf Surface ◽  
Escherichia Coli O157 ◽  
Adaxial Side ◽  
Abaxial Side ◽  
E Coli ◽  
Lactuca Sativa L ◽  
Leaf Surfaces ◽  
Leaves And Roots ◽  
Leaf Lettuce

Survival and internalization characteristics of Escherichia coli O157:H7 in iceberg, romaine, and leaf lettuce after inoculation of leaf surfaces and soil were determined. A five-strain mixture of E. coli O157:H7 in water and cow manure extract was used as an inoculum for abaxial and adaxial sides of leaves at populations of 6 to 7 log and 4 log CFU per plant. The five strains were individually inoculated into soil at populations of 3 and 6 log CFU/g. Soil, leaves, and roots were analyzed for the presence and population of E. coli O157:H7. Ten (4.7%) of 212 samples of leaves inoculated on the adaxial side were positive for E. coli O157:H7, whereas 38 (17.9%) of 212 samples inoculated on the abaxial side were positive. E. coli O157:H7 survived for at least 25 days on leaf surfaces, with survival greater on the abaxial side of the leaves than on the adaxial side. All 212 rhizosphere samples and 424 surface-sanitized leaf and root samples from plants with inoculated leaves were negative for E. coli O157:H7, regardless of plant age at the time of inoculation or the location on the leaf receiving the inoculum. The pathogen survived in soil for at least 60 days. Five hundred ninety-eight (99.7%) of 600 surface-sanitized leaf and root samples from plants grown in inoculated soil were negative for E. coli O157:H7. Internalization of E. coli O157:H7 in lettuce leaves and roots did not occur, regardless of the type of lettuce, age of plants, or strain of E. coli O157:H7.

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