Calcium requirements of plants

1969 ◽  
Vol 20 (3) ◽  
pp. 465 ◽  
Author(s):  
JF Loneragan ◽  
K Snowball
Keyword(s):  
Calcium Concentration ◽  
Dry Weight ◽  
Calcium Deficiency ◽  
Critical Values ◽  
Functional Requirement ◽  
Functional Requirements ◽  
Constant Concentration ◽  
Excess Calcium ◽  
Wide Range ◽  
Calcium Supply

Calcium concentrations in the tops and roots of 30 grasses, cereals, legumes, and herbs were examined for plants grown over a wide range of calcium concentrations (0.3 to 1000 µM) which were maintained constant in flowing culture solutions of pH 5.7. When plants were grown continuously in solutions of constant concentration, the relation between the calcium concentration in tops and the yield generally showed two regions. Increasing solution calcium concentrations from 0.3 to 2.5 µM increased the yield greatly, while calcium concentrations in the tops remained constant. By contrast, increasing solution concentrations from 10 to 1000 µM markedly increased concentrations in tops but in most species had relatively small effects on yield. At luxury calcium supply the concentrations in herb and legume tops were very much higher than those of grasses and cereals and were surprisingly similar to those of the same species grown in soil in the field. That calcium concentration in plant tops which remained constant while yield increased substantially is believed to indicate the minimal functional requirement of the tops for calcium. The average functional requirements of herb and legume tops (0.1–0.2% dry weight) were generally much lower than previously reported but were about twice those of grasses and cereals (0.05–0.1%). With the exception of Lupinus spp., no legume or herb had functional calcium requirements as low as those of any grass or cereal. When plants were transferred from 1000 to 0.3 µM calcium concentrations, they developed calcium deficiency symptoms and grew less than plants which had one-third to one-tenth the calcium concentrations in their tops but which had been grown continuously in solutions of low and constant concentration (2.5–10 µM). Excess calcium accumulated in the old leaves during luxury calcium supply but was not mobilized when plants were transferred to calcium-deficient solutions. It is suggested that variation in the conditions of calcium supply under which calcium deficiency develops partly accounts for the wide range of critical values used by various workers to diagnose deficiency in plants.

Rate of calcium absorption by plant roots and its relation to growth

1969 ◽  
Vol 20 (3) ◽  
pp. 479 ◽  
Author(s):  
JF Loneragan ◽  
K Snowball
Keyword(s):  
Calcium Absorption ◽  
Calcium Deficiency ◽  
Root Weight ◽  
Functional Requirements ◽  
Relative Growth Rates ◽  
Plant Groups ◽  
Plant Group ◽  
Wide Range ◽  
Standard Culture ◽  
Almost All

Rates of calcium absorption per unit root weight were measured for each of three successive weeks for 30 grasses, cereals, legumes, and herbs grown in flowing culture solutions of pH 5.7 with a wide range of calcium concentrations (0.3 to 1000 µM) which were maintained constant. Plants did not absorb calcium from 0.3 µM solutions and absorbed little from 0.8 µM solutions. Increasing solution concentrations from 0.8 to 10 µM increased the average rates of calcium absorption almost linearly in all plant groups: increasing solution concentrations to 100 or 1000 µM increased rates of calcium absorption but with decreasing effectiveness. Rates of absorption generally remained constant during the experiment, except that in grasses and cereals at 100 and 1000 µM calcium they tended to fall with time. At concentrations from 2.5 to 1000 µM, the average rates of calcium absorption by roots of legumes and herbs were generally very much higher than those by equal weights of grass and cereal roots. Individual cultivars within each plant group tended to follow the average behaviour, so that almost all legumes and herbs absorbed calcium very much faster (up to 15 times) than grasses and cereals at all solution concentrations above 2.5 µM. The relationship between rates of calcium absorption and plant growth is discussed. Since excess calcium accumulated in plants is not readily mobilized to developing tissues, plants become calcium-deficient as soon as the rate of calcium absorption falls below the functional requirements of the tissues. Absorption rater of 0.5 µg atom in grasses and cereals, and in herbs and legumes of 1 µg atom per gram fresh roots per day are suggested as minimal to maintain relative growth rates of c. 9% per day. In standard culture solutions legumes and herbs would deplete calcium from solution and hence develop calcium deficiency more quickly than cereals and grasses. By contrast, in flowing culture solutions with low calcium concentrations maintained constant, high rates of calcium absorption by legumes and herbs sometimes offset their high tissue requirements for calcium; this explains why some legumes and herbs are able to grow at lower calcium concentrations than some grasses and cereals. It is suggested that conditions of calcium supply under which deficiency develops in solutions and in soils should be taken into account when assessing the relative susceptibility of plant species to calcium deficiency.

Diet of European freshwater pearl mussels Margaritifera margaritifera (Mollusca: Bivalvia: Unionoida) in small river (Republic of Karelia, Russia)

2021 ◽  
Vol 325 (4) ◽  
pp. 502-515
Author(s):  
S.F. Komulaynen
Keyword(s):  
Algal Species ◽  
Dry Weight ◽  
Lake Ladoga ◽  
Total Biomass ◽  
Margaritifera Margaritifera ◽  
Pearl Mussel ◽  
Organic Detritus ◽  
Unicellular Algae ◽  
Wide Range ◽  
Intestinal Contents

The freshwater pearl mussel Margaritifera margaritifera (Linnaeus,1758) is endangered in Europe and is now listed in the Red Data Book of many countries and regions. The diet of the species in the Syskyänjoki River (a tributary of Lake Ladoga) has been studied. The contents of the intestine generally correspond to the composition of seston, and include organic detritus, filamentous and unicellular algae, fragments of invertebrates and macrophyte tissues mixed with silt and sand. The total biomass of the intestinal contents of varied from 0.8 to 30.6 mg per organism (absolutely dry weight). Margaritifera margaritifera consumes a wide range of particles, from 0.5 μm3 (bacteria and unicellular algae) to 200 000 μm3 (fragments of invertebrates and macrophyte tissues). About 90–95% (by volume) of the intestinal contents was consisted by fine organic detritus. The food composition did not differ significantly for mollusks of different sexes and size. In the intestinal contents, 63 taxa of algae were identified. The number of algal species in the content of one intestine varied from 3 to 17, with their abundance from 250 to 9560 cells per organism. The most abundant and constant in the contents of the intestines are unicellular algae. Diatoms are the most diverse, they make up 50.8% of the total number of species.

Third generation progress in breeding white clover for resistance to root-knot nematode

1996 ◽  
Vol 6 ◽  
pp. 163-166
Author(s):  
J. Van den Bosch ◽  
C.F. Mercer
Keyword(s):  
White Clover ◽  
Trifolium Repens ◽  
Egg Production ◽  
Control Method ◽  
Dry Weight ◽  
Third Generation ◽  
Root Knot Nematode ◽  
Root Dry Weight ◽  
Wide Range ◽  
Meloidogyne Sp

Root-knot nematode (Meloidogyne sp.) reduces growth and nutrition of white clover (Trifolium repens L.) in New Zealand, and breeding resistant cultivars (with low galls per gram of root) is the preferred control method. Resistant and susceptible selections were bred from a wide range of white clover lines for three generations. In the third generation there were significant differences between seed lines from the selections for number of galls, root dry weight, visual growth score and galls/gram of root dry weight. Resistant selections had 43% of the susceptible selections' galls per gram, and 50% of the number of galls. Germplasm showing resistance to Meloidogyne spp. in the USA showed partial resistance to the local Meloidogyne sp. Two resistant and two susceptible genotypes were also compared for nematode egg production; resistant genotypes had a mean of 3,460 eggs/plant, compared to 25,030 for susceptible genotypes. Keywords: breeding, Meloidogyne sp., resistance, rootknot nematode, screening, selection, Trifolium repens, white clover

Critical Values in Anatomic Pathology

2006 ◽  
Vol 130 (5) ◽  
pp. 638-640 ◽  
Author(s):  
Jan F. Silverman ◽  
Telma C. Pereira
Keyword(s):  
Patient Safety ◽  
Improve Patient Safety ◽  
Clinical Pathology ◽  
Critical Values ◽  
Surgical Pathology ◽  
Anatomic Pathology ◽  
Wide Range ◽  
Enhance Patient Safety ◽  
Pathology Reports ◽  
Improve Patient

Abstract Similar to critical values (CVs) in clinical pathology, occasional diagnoses in surgical pathology and cytology could require immediate notification of the physician to rapidly initiate treatment. However, there are no established CV guidelines in anatomic pathology. A retrospective review of surgical pathology reports was recently conducted to study the incidence of CVs in surgical pathology and to survey the perceptions of pathologists and clinicians about CVs in surgical pathology, with a similar analysis of CVs performed in cytology. The results indicated that CVs in surgical pathology and cytology are uncommon but not rare and that there is a wide range of opinion among pathologists and between pathologists and clinicians about the need for an immediate telephone call and about the degree of urgency. It was obvious from the study that there is a lack of consensus in identifying what constitutes surgical pathology and cytology CV cases. Since the Institute of Medicine's report on medical errors, there has been an increasing number of initiatives to improve patient safety. Having guidelines for anatomic pathology CVs could enhance patient safety, in contrast to the current practice in which CV cases are managed based on common sense and on personal experience. Therefore, a discussion involving the pathology community might prove useful in an attempt to establish anatomic pathology CV guidelines that could represent a practice improvement.

scholarly journals Cd and Zn interactions and toxicity in ectomycorrhizal basidiomycetes in axenic culture

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4478 ◽  
Author(s):  
Vinicius H. De Oliveira ◽  
Mark Tibbett
Keyword(s):  
Radial Growth ◽  
Solid Medium ◽  
Axenic Culture ◽  
Dry Weight ◽  
Zinc Toxicity ◽  
Solid Media ◽  
Wide Range ◽  
Ecm Fungi ◽  
Ectomycorrhizal Basidiomycetes ◽  
Tolerance Indices

BackgroundMetal contamination in soils affects both above- and belowground communities, including soil microorganisms. Ectomycorrhizal (ECM) fungi are an important component in belowground community and tolerant strains have great potential in enhancing plant-based remediation techniques. We assessed cadmium and zinc toxicity in five ECM species in liquid media (Hebeloma subsaponaceum;H. cylindrosporum;H. crustuliniforme;Sclerodermasp.;Austroboletus occidentalis) and investigated the potential of Zn to alleviate Cd toxicity. Due to highly divergent results reported in the literature, liquid and solid media were compared experimentally for the first time in terms of differential toxicity thresholds in Cd and Zn interactions.MethodsA wide range of Cd and Zn concentrations were applied to ectomycorrhizal fungi in axenic cultures (in mg L−1): 0; 1; 3; 9; 27; 81; 243 for the Cd treatments, and 0; 1; 30; 90; 270; 810; 2,430 for Zn. Combined Zn and Cd treatments were also applied toH. subsaponaceumandSclerodermasp. Dry weight was recorded after 30 days, and in case of solid medium treatments, radial growth was also measured.Results and DiscussionAll species were adversely affected by high levels of Cd and Zn, andA. occidentaliswas the most sensitive, with considerable biomass decrease at 1 mg L−1Cd, whileSclerodermasp. andH. subsaponaceumwere the most tolerant, which are species commonly found in highly contaminated sites. Cd was generally 10 times more toxic than Zn, which may explain why Zn had little impact in alleviating Cd effects. In some cases, Cd and Zn interactions led to a synergistic toxicity, depending on the concentrations applied and type of media used. Increased tolerance patterns were detected in fungi grown in solid medium and may be the cause of divergent toxicity thresholds found in the literature. Furthermore, solid medium allows measuring radial growth/mycelial density as endpoints which are informative and in this case appeared be related to the high tolerance indices found inH. subsaponaceum.

scholarly journals Rhizobacteria inoculation in maize associated with nitrogen and zinc fertilization at sowing

2021 ◽  
Vol 25 (2) ◽  
pp. 96-100
Author(s):  
Andréia de L. Moreno ◽  
Jorge F. Kusdra ◽  
Angelita A. C. Picazevicz
Keyword(s):  
Bacillus Subtilis ◽  
Nitrogen Content ◽  
Plant Height ◽  
Nitrogen Fertilization ◽  
Azospirillum Brasilense ◽  
Dry Weight ◽  
Stem Diameter ◽  
Wide Range ◽  
Maize Plants ◽  
Total Dry Weight

ABSTRACT Rhizobacteria have a wide range of plant growth-promoting mechanisms of action, making them an alternative and/or complementary biological input for chemical fertilizers. In this respect, the present study aimed to assess growth and nitrogen accumulation in maize plants as a function of Azospirillum brasilense, Bacillus subtilis, zinc and nitrogen application at sowing. The experiment with the ‘AL Bandeirante’ maize variety was conducted in a greenhouse, using a completely randomized design. The treatments were arranged in a 2 x 2 x 2 x 2 factorial scheme, with six repetitions, considering the presence and absence of Azospirillum brasilense (5 g kg-1), Bacillus subtilis (5 mL kg-1) and zinc (20 g kg-1) in the seeds and addition or not of nitrogen (30 kg ha-1) to the soil. The variables assessed were plant height, stem diameter, leaf, stem, shoot, root and total dry weight, and shoot nitrogen content. Nitrogen fertilization in the absence of zinc increased shoot and total dry weight as well as shoot nitrogen content. Zinc applied to the seeds improved the total and stem dry weight of maize plants in the absence of Bacillus subtilis. Inoculation with Azospirillum brasilense and Bacillus subtilis increased the stem diameter and shoot nitrogen content of maize plants when nitrogen fertilization was not performed at sowing. There was no isolated or interaction effect between factors for plant height and root dry weight.

scholarly journals HIGH RESOLUTION CAMERA DESIGN PLANNING THEORETICAL FOUNDATIONS FOR DRIVING SYSTEMS

2021 ◽  
Author(s):  
Viacheslav S. Stadnichuk ◽  
Valentin G. Kolobrodov ◽  
Oleksii O. Mosolab ◽  
Denis Yu. Kondratenko ◽  
Dmytro I. Ryabokon
Keyword(s):  
High Resolution ◽  
Optical Glass ◽  
Light Sensitivity ◽  
Design Parameters ◽  
Optical Parameters ◽  
Functional Requirements ◽  
Modulation Transfer ◽  
Road Signs ◽  
Wide Range ◽  
Camera Design

Background. Analysis of statistical data showed that in most cases the cause of the accident is driver error and, as a consequence, violation of traffic rules. In this regard, over the past 10 years, active developments in the field of recognition of road signs and other obstacles in the path of a car have been actively developing. Car manufacturers offer ready-made built-in systems, mounted behind the interior rearview mirror and connected to the car’s on-board computer, which carries out further control of the car in a critical situation. The main disadvantage of these systems of this class is the low range of recognition of road signs, the dependence of optical parameters on temperature and low light sensitivity. Objective. The purpose of the paper is to model an athermal objective for a high-resolution camera, investigate the characteristics of lenses depending on the ambient temperature. Methods. Analysis and modeling of objectives, lenses, optical glass from different materials. Results. A high-resolution camera objective for all types of cars is proposed. An athermal objective was developed for a high-resolution camera. Conclusions. The optimized athermal design of the visible spectrum objective for long-range car cameras is considered. Car cameras typically have a fixed focus, and forward-facing cameras typically require relatively long focal lengths to provide information about distant objects. The optical system for these cameras should provide high resolution, as well as operate in a wide range of ambient temperatures. The camera design parameters are derived from the functional requirements of road sign recognition at a distance of 200 m. The objective design has five lenses with spherical surfaces. The objective has a relative aperture of f/2 and a modulation transfer function (MTF) of more than 0.5 at 111 l/mm over the entire temperature range.

scholarly journals Stilbenes in the different organs of Vitis vinifera cv. Merlot grafted on Teleki Kober 5BB rootstock

OENO One ◽  
2017 ◽  
Vol 51 (3) ◽  
pp. 323 ◽  
Author(s):  
Gyöngyi Németh ◽  
Orsolya Hegyi ◽  
Attila Dunai ◽  
Laszlo Kocsis
Keyword(s):  
Vitis Vinifera ◽  
Field Study ◽  
Primary Source ◽  
Dry Weight ◽  
Shoot Tips ◽  
Font Size ◽  
Plant Organs ◽  
Wide Range ◽  
Berry Skins ◽  
Winter Buds

<p style="text-align: justify;"><span style="font-size: medium;"><strong>Aim: </strong>To determine which of the grapevine organ is the richest in stilbene, like the t-piceid, t-resveratrol and ε-viniferin and would it be useful as by-product of viticulture for processing stilbene concentrate.</span></p><p style="text-align: justify;"><span style="font-size: medium;"><strong>Methods and results: </strong>Nine organs, such as cane, buds, shoot tips, inflorescences, clusters at veraison, matured berry skins, seeds and cluster stems, of Merlot grafted on Teleki Kober 5BB rootstock were collected during a year and its ethanolic extractions were analyzed via HPLC-FLD. Stilbene content of the different organs occurred in a wide range, the lowest was 3.15 mg/kg dry weight (dw) measured in the seeds and the highest 2265 mg/kg dw in the buds.</span></p><p style="text-align: justify;"><span style="font-size: medium;"><strong>Conclusion:</strong> The present research demonstrated that different grapevine organs contain different amount of stilbene in the vineyard. The winter-buds, the roots and the matured cane internodes of Merlot are significantly richer in t-resveratrol and t-ε-viniferin than the green vegetative and generative parts we examined in one growing year. </span></p><p style="text-align: justify;"><span style="font-size: medium;"><strong>Significance and impact of the study: </strong>According to our knowledge there was no stilbenes measuring in several plant organs of a vine cultivar in field study, in vineyard. Our research pointed out the pruned cane could be primary source of stilbene of the health-industry. Beside that grape root is a by-product of grapevine nursery is also rich in stilbene. </span></p>

scholarly journals An 112 Days Experiment on Dietary Cadmium Retention in Hepatopancreas in Adult Cantareus aspersus Snails

2019 ◽  
Vol 70 (8) ◽  
pp. 2803-2804
Author(s):  
George A. Draghici ◽  
Cristina A. Dehelean ◽  
Iulia Pinzaru ◽  
Despina M. Bordean ◽  
Georgeta Pop ◽  
...  
Keyword(s):  
Absorption Spectrometry ◽  
Dry Weight ◽  
Land Snails ◽  
Dependent Manner ◽  
Flame Atomic Absorption ◽  
Wide Range ◽  
Cantareus Aspersus ◽  
Ecotoxicological Model ◽  
Dietary Cadmium ◽  
Kinetics Of

Cadmium is very hazardous pollutant with massive impact on aspects of everyday life. Little knowledge exists on kinetics of dietary cadmium retention in Cantareus aspersus for durations above three months although this species of land snails serves as excellent ecotoxicological model for studying cadmium hazard. Here was used a continuous 112-day exposure study design, in which test snails were exposed to a wide range of dietary cadmium levels, including human- and environmentally-relevant levels. Using Flame Atomic Absorption Spectrometry, cadmium levels in the hepatopancreas were found to increase significantly, and in dose-dependent manner starting from a dietary cadmium dose of 0.2 mg/kg dry weight. The results of the present study render the hepatopancreas of mature snails, C. aspersus, as excellent endpoints for assessing Cd toxicity over a broad range of concentrations. Hence, this species of land snails can be reliably used for both active and passive biomonitoring of environmental cadmium pollution.

scholarly journals NON FUNCTIONAL REQUIREMENTS (NFRS) TRACEABILITY METAMODEL FOR AGILE DEVELOPMENT

2015 ◽  
Vol 77 (9) ◽  
Author(s):  
Adila Firdaus ◽  
Imran Ghani ◽  
Dayang Norhayati Abg Jawawi ◽  
Wan Mohd Nasir Wan Kadir
Keyword(s):  
Process Model ◽  
Full Scale ◽  
Agile Development ◽  
Functional Requirement ◽  
Functional Requirements ◽  
Agile Methodologies ◽  
And Performance ◽  
Requirement Changes ◽  
Recall Methods

Agile methodologies are well known for early and frequent releases. Besides, these methodologies also handle requirement changes well without causing delays. However, it has been noticed that the functional requirements changes can affect the non-functional requirements (NFRs) such as security and performance. It is also possible that the agile team is not even aware of these effects causing dysfunctional system. This issue could be addressed by offering traceability mechanism that helps to trace the effect of functional requirement changes on the non-functional requirements. Unfortunately, a few researchers have conducted studies regarding this issue. Thus, this study attempts to present a Traceability Process Model (TPM) to tackle the issue of tracing NFR especially security and performance. However, to materialize a full scale TPM, a metamodel is necessary. Therefore in this paper, we present a metamodel by integrating two existing metamodels. Then we validate the newly built metamodel with precision and recall methods. Lastly, we also develop a traceability tool that is based on the proposed metamodel.

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