scholarly journals MANGANESE DEFICIENCY AND TOXICITY IN GREENHOUSE TOMATOES

1977 ◽  
Vol 57 (1) ◽  
pp. 107-115 ◽  
Author(s):  
G. M. WARD
Keyword(s):  
Lycopersicon Esculentum ◽  
Threshold Value ◽  
Sand Culture ◽  
Manganese Deficiency ◽  
Mn Toxicity ◽  
Severe Deficiency ◽  
Wide Range ◽  
Mn Content ◽  
Greenhouse Tomatoes ◽  
Apparently Healthy

Symptoms of manganese deficiency and toxicity on greenhouse tomatoes (Lycopersicon esculentum Mill.), produced experimentally in sand culture, were related to Mn content determined in tissues of leaves, petioles, stems, suckers, roots, and fruits. The highest concentration of Mn found in tissue showing deficiency symptoms was 25 ppm, although this level of Mn also was found in some healthy tissues. Severe deficiency was associated with all tissues, except fruit, that contained 20 ppm Mn or less. An exact threshold value for the onset of Mn toxicity was difficult to define, but probably occurred between 450 and 500 ppm for young top leaves and between 900 and 1,000 ppm for older lower leaves. The tomato plant will tolerate a wide range of Mn levels in apparently healthy tissue.

SULPHUR DEFICIENCY AND TOXICITY SYMPTOMS IN GREENHOUSE TOMATOES AND CUCUMBERS

1976 ◽  
Vol 56 (1) ◽  
pp. 133-137 ◽  
Author(s):  
G. M. WARD
Keyword(s):  
Lycopersicon Esculentum ◽  
Plant Tissue ◽  
Fruit Production ◽  
Sand Culture ◽  
Plant Tissues ◽  
Morphological Effect ◽  
Sulphur Deficiency ◽  
Lycopersicon Esculentum Mill ◽  
Severe Deficiency ◽  
Greenhouse Tomatoes

Symptoms of sulphur deficiency and toxicity on greenhouse tomatoes (Lycopersicon esculentum Mill.) and cucumbers (Cucumis sativis L.) were produced experimentally in sand culture and are described in detail. The principal morphological effect was a general depression of growth and fruit production. A S content of less than 0.25% in any plant tissue was associated with severe deficiency. The distribution of S in various plant tissues is shown.

MAGNESIUM DEFICIENCY IN GREENHOUSE TOMATOES

1969 ◽  
Vol 49 (1) ◽  
pp. 53-59 ◽  
Author(s):  
Gordon M. Ward ◽  
Marcia J. Miller
Keyword(s):  
Magnesium Deficiency ◽  
Tissue Level ◽  
Sand Culture ◽  
Tissue Analysis ◽  
Culture Experiment ◽  
Deficiency Symptoms ◽  
Severe Deficiency ◽  
Wide Range ◽  
Adequate Sampling ◽  
Greenhouse Tomatoes

In a sand culture experiment with greenhouse tomatoes, tissue analysis of plant samples showing a wide range of magnesium deficiency symptoms indicated that a tissue level of 0.30% Mg was associated with incipient deficiency and the beginning of symptom expression, while a level of 0.15% or less was associated with severe deficiency symptoms. These are definite values and it is suggested that they may be applicable to many crop plants, provided adequate sampling and accurate analyses are carried out.

scholarly journals High Zinc Concentrations Contribute to Chlorosis in Blueberry

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 880D-880
Author(s):  
C.L. Gupton ◽  
J.M. Spiers
Keyword(s):  
Total Concentration ◽  
Sand Culture ◽  
Plant Leaves ◽  
Mn Toxicity ◽  
Zn Concentration ◽  
High Zinc ◽  
Zinc Concentrations ◽  
Mn Content ◽  
Southern Highbush ◽  
Fertilization Level

To determine if high Zn concentrations contribute to chlorosis in blueberry, plants of rabbiteye `Climax' and southern highbush `Bladen' were fertilized in sand culture with 30, 60, 90, and 120 ppm Zn solutions at 4, 4.5, 5, 5.5, 6, and 6.5 pH. Only Zn levels significantly affected the degree of chlorosis in plant leaves. No interaction among cultivars, pH, or Zn concentration was significant. The linear response to Zn levels was significant (P = 0.0001), but quadratic and cubic responses were not significant. Cultivars and Zn fertilization levels affected Zn and Mn accumulation; however, no difference in chlorosis rating was observed between cultivars. An inverse relationship existed between Zn fertilization levels and leaf Mn content so that the total concentration of the two minerals was about the same for each fertilization level, suggesting that Mn toxicity would not be expected at high levels of Zn fertilization. We concluded that high levels of Zn may induce chlorosis in rabbiteye and southern highbush blueberry.

CALCIUM DEFICIENCY SYMPTOMS IN GREENHOUSE CUCUMBERS

1973 ◽  
Vol 53 (4) ◽  
pp. 849-856 ◽  
Author(s):  
G. M. WARD
Keyword(s):  
Leaf Tissue ◽  
Threshold Value ◽  
Calcium Deficiency ◽  
Sand Culture ◽  
Tissue Analysis ◽  
Culture Experiment ◽  
Cucumis Sativus L ◽  
Green Color ◽  
Ca Deficiency ◽  
Severe Deficiency

In a sand culture experiment with seeded and seedless greenhouse cucumbers (Cucumis sativus L.), induced Ca deficiency over a range of nutrient Ca applications produced characteristic foliar and plant symptoms. Severe deficiency was associated with top leaf tissue levels of 0.20% Ca and less. Fruit symptoms were a proportionate stunting, center and stem-end constriction in Burpee hybrid, and a progressively darker green color in Sporu. Mild symptoms were difficult to recognize and could only be confirmed by tissue analysis, although it was not possible to determine an exact threshold value for incipient deficiency.

scholarly journals HERITABILITY OF MANGANESE TOLERANCE IN RABBITEYE BLUEBERRY

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1075e-1075
Author(s):  
Creighton Gupton ◽  
James Spiers
Keyword(s):  
Genetic Correlation ◽  
Diallel Cross ◽  
Sand Culture ◽  
Mass Selection ◽  
Narrow Sense Heritability ◽  
Vaccinium Ashei ◽  
Mn Toxicity ◽  
Manganese Tolerance ◽  
Mn Content ◽  
Shoot Weight

To determine whether manganese tolerance in rabbiteye blueberry (Vaccinium ashei Reade) is heritable, a 10-parent diallel cross was produced. A 250 ppm Mn solution (200 ml/plant) was applied to a sand culture, of the progeny daily. Visual ratings (1 - dead plant - 13 - no Mn toxicity symptom) were made after 6 weeks. Shoot weight and Mn content of leaves were determined. Narrow-sense heritability estimates (h2) were 0.45±0.28 for Mn content, 0.49±0.27 for visual ratings, and 0.37± 0.21 for shoot weight. The genetic correlation between neither shoot weight nor visual rating and Mn content (0.11 and -0.15, respectively) was very high; however, the correlation between shoot weight and visual ratings (1.00) was extremely high. This suggests that visual ratings provide an estimate of Mn effects on plans equal to objective measurements of shoot weight. Though h2 estimates for Mn content and visual ratings were similar, the lack of genetic correlation between the traits indicates that tolerance to Mn toxicity is independent of Mn content. The high h2 for visual ratings suggests mass selection as the method of choice for improving Mn tolerance in a rabbiteye blueberry population.

scholarly journals Effects of urban atmospheric particulate matter on higher plants using Lycopersicon esculentum as model species

2021 ◽  
Vol 3 (9) ◽  
Author(s):  
Katalin Hubai ◽  
Nora Kováts ◽  
Gábor Teke
Keyword(s):  
Particulate Matter ◽  
Lycopersicon Esculentum ◽  
Protein Content ◽  
Higher Plants ◽  
Nutrient Content ◽  
Atmospheric Particulate Matter ◽  
Dose Effect ◽  
Atmospheric Particulate ◽  
Wide Range ◽  
Treatment Experiment

AbstractAtmospheric particulate matter (PM) is one of the major environmental concerns in Europe. A wide range of studies has proved the ecotoxic potential of atmospheric particles. PM exerts chemical stress on vegetation by its potentially toxic constituents; however, relatively few studies are available on assessing phytotoxic effects under laboratory conditions. In our study, aqueous extract of particulate matter was prepared and used for treatment. Experiment was following the procedure defined by the No. 227 OECD Guideline for the Testing of Chemicals: Terrestrial Plant Test. Tomato (Lycopersicon esculentum Mill.) plants were used; elucidated toxicity was assessed based on morphological and biochemical endpoints such as biomass, chlorophyll-a and chlorophyll-b, carotenoids, and protein content. Biomass reduction and protein content showed a clear dose–effect relationship; the biomass decreased in comparison with the control (100%) in all test groups (TG) at a steady rate (TG1: 87.73%; TG2: 71.77%; TG3: 67.01%; TG4: 63.63%). The tendency in protein concentrations compared to the control was TG1: 113.61%; TG2: 148.21% TG3: 160.52%; TG4: 157.31%. However, pigments showed a ‘Janus-faced’ effect: nutrient content of the sample caused slight increase at lower doses; actual toxicity became apparent only at higher doses (chlorophyll-a concentration decrease was 84.47% in TG4, chlorophyll-b was 77.17%, and finally, carotene showed 83.60% decrease in TG4).

The role of slow magnetostrophic waves in dipole formation in rapidly rotating dynamos

2021 ◽  
Author(s):  
Aditya Varma ◽  
Binod Sreenivasan
Keyword(s):  
Magnetic Field ◽  
Threshold Value ◽  
Dipole Field ◽  
Wave Frequency ◽  
Alfven Wave ◽  
Inertial Waves ◽  
Axial Dipole ◽  
Wide Range ◽  
The Magnetic Field

<p>It is known that the columnar structures in rapidly rotating convection are affected by the magnetic field in ways that enhance their helicity. This may explain the dominance of the axial dipole in rotating dynamos. Dynamo simulations starting from a small seed magnetic field have shown that the growth of the field is accompanied by the excitation of convection in the energy-containing length scales. Here, this process is studied by examining axial wave motions in the growth phase of the dynamo for a wide range of thermal forcing. In the early stages of evolution where the field is weak, fast inertial waves weakly modified by the magnetic field are abundantly present. As the field strength(measured by the ratio of the Alfven wave to the inertial wave frequency) exceeds a threshold value, slow magnetostrophic waves are spontaneously generated. The excitation of the slow waves coincides with the generation of helicity through columnar motion, and is followed by the formation of the axial dipole from a chaotic, multipolar state. In strongly driven convection, the slow wave frequency is attenuated, causing weakening of the axial dipole intensity. Kinematic dynamo simulations at the same parameters, where only fast inertial waves are present, fail to produce the axial dipole field. The dipole field in planetary dynamos may thus be supported by the helicity from slow magnetostrophic waves.</p>

scholarly journals Insulin sensitivity variations in apparently healthy Arab male subjects: correlation with insulin and C peptide

2021 ◽  
Vol 9 (2) ◽  
pp. e002039
Author(s):  
Noor Suleiman ◽  
Meis Alkasem ◽  
Shaimaa Hassoun ◽  
Ibrahem Abdalhakam ◽  
Ilham Bettahi ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Insulin Sensitivity ◽  
Inflammatory Markers ◽  
The Other ◽  
Whole Body ◽  
Oxidative Stress Markers ◽  
C Peptide ◽  
Stress Markers ◽  
Wide Range ◽  
Apparently Healthy

IntroductionDecreased insulin sensitivity occurs early in type 2 diabetes (T2D). T2D is highly prevalent in the Middle East and North Africa regions. This study assessed the variations in insulin sensitivity in normal apparently healthy subjects and the levels of adiponectin, adipsin and inflammatory markers.Research design and methodsA total of 60 participants (aged 18–45, body mass index <28) with a normal oral glucose tolerance test (OGTT) completed hyperinsulinemic-euglycemic clamp (40 mU/m2/min) and body composition test by dual-energy X-ray absorptiometry scan. Blood samples were assayed for glucose, insulin, C peptide, inflammatory markers, oxidative stress markers, adiponectin and adipsin.ResultsThe subjects showed wide variations in the whole-body glucose disposal rate (M value) from 2 to 20 mg/kg/min and were divided into three groups: most responsive (M>12 mg/kg/min, n=17), least responsive (M≤6 mg/kg/min, n=14) and intermediate responsive (M=6.1–12 mg/kg/min, n=29). Insulin and C peptide responses to OGTT were highest among the least insulin sensitive group. Triglycerides, cholesterol, alanine transaminase (ALT) and albumin levels were higher in the least responsive group compared with the other groups. Among the inflammatory markers, C reactive protein (CRP) was highest in the least sensitivity group compared with the other groups; however, there were no differences in the level of soluble receptor for advanced glycation end products and Tumor Necrosis Factor Receptor Superfamily 1B (TNFRS1B). Plasma levels of insulin sensitivity markers, adiponectin and adipsin, and oxidative stress markers, oxidized low-density lipoprotein, total antioxidant capacity and glutathione peroxidase 1, were similar between the groups.ConclusionsA wide range in insulin sensitivity and significant differences in triglycerides, cholesterol, ALT and CRP concentrations were observed despite the fact that the study subjects were homogenous in terms of age, gender and ethnic background, and all had normal screening comprehensive chemistry and normal glucose response to OGTT. The striking differences in insulin sensitivity reflect differences in genetic predisposition and/or environmental exposure. The low insulin sensitivity status associated with increased insulin level may represent an early stage of metabolic abnormality.

scholarly journals Evaluation of a screening technique for manganese toxicity in relation to leaf manganese distribution and interaction with silicon.

1981 ◽  
Vol 29 (4) ◽  
pp. 297-304
Author(s):  
C.R. Blatt ◽  
A. van Diest
Keyword(s):  
Manganese Toxicity ◽  
Test Solution ◽  
High Toxicity ◽  
Mn Toxicity ◽  
Screening Technique ◽  
Manganese Tolerance ◽  
Nutrient Culture ◽  
Mn Content ◽  
Leaves And Roots

A screening technique utilizing a flowing nutrient culture was used to evaluate 20 lettuce cultivars differing in the severity of the toxicity symptoms marginal yellowing and necrosis in older leaves. Growth, leaf and root Mn contents and toxicity ratings (1 = no symptoms to 5 = high toxicity) were recorded over six Mn and two Si concentrations. A test solution of 0.5-1.0 mg/l Mn produced consistent toxicity ratings and the ratings for tolerant and sensitive cultivars were similar to ratings for the same cultivars grown under glasshouse conditions. Total Mn content in leaves was not a useful index for Mn sensitivity. Increased Si resulted in a repression of toxicity symptoms and decreased shoot/root Mn ratios in 12 cultivars. ADDITIONAL ABSTRACT: A screening technique was developed to evaluate lettuce cultivars for manganese tolerance in flowing nutrient culture. Considerable variation in the sensitivity of 20 cultivars was observed, as shown by visible symptoms. However there was no correlation between accumulation of Mn in leaves and roots and the degree of Mn tolerance. Increasing silicon in the solution repressed Mn toxicity symptoms, but had variable effects on the Mn content of leaves and roots. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Solvent-Induced Damage in Polyimide Thin Films

1989 ◽  
Vol 167 ◽  
Author(s):  
M. S. Hu
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Exposure Time ◽  
Critical Strain ◽  
Threshold Value ◽  
Weak Dependence ◽  
Polyimide Films ◽  
Band Formation ◽  
Enhanced Diffusion ◽  
Wide Range

AbstractSolvent induced damage bands formed in residually strained polyimide thin films on different substrates have been studied. Microscopy studies have shown that these bands resemble crazes. A mechanics approach Is taken to understand the band formation phenomenon.The critical strain for damage formation has been identified. This strain decreases with increase in exposure time, but always exhibits a threshold value. In contrast to the cracking of brittle films, the critical strain has only a weak dependence on the film thickness over a wide range. This behavior obtains because the crazing of the polyimide films is nucleation controlled. Strain-enhanced diffusion of solvent into the films is considered to be responsible for the property degradation that leads to damage formation.

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