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Effect of nitrogen on the oxalate and calcium content of Kikuyu grass (Pennisetum clandestinum Hochst)
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: J.P. Marais --- , Republic of South AfricaThe effect of the nitrogen content of Kikuyu grass (Pennisetum clandestinum) on the oxalate and calcium content of leaf and stem material was investigated. The grass contained equal portions of soluble and insoluble oxalate. Leaf material contained more than three... -
Fisiologiese blaarabnormaliteite en bolopbrengs by katoen (Gossypium hirsutum L.) soos deur kalium-, kalsium- en boorvoeding beïnvloed
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N. J.J. Combrink --- Navorsingsinstituut vir Tabak en Katoen,Physiological leaf abnormalities and boll yield of cotton (Gossypium hirsutum L.) as affected by potassium, calcium and boron nutrition. A pot trial with a sand medium and two levels each of K, Ca and B nutrition, factorially arranged, was carried... -
Effect of Ca, K and B supply on water-stress induced chlorophyll loss from tobacco and cotton leaf discs
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: ElizabethA. Davies --- , England N. J.J. Combrink --- , Republic of South AfricaA study was made of the influence of Ca:K ratios and B levels on the chlorophyll content of tobacco and cotton leaves grown under glasshouse conditions. Excised leaf discs were floated on a solution of polyethylene glycol 6000 to study... -
Effect of Ca, K and B supply on growth of cotton (Gossypium hirsutum L.) and tobacco (Nicotiana tabacum L.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: N. J.J. Combrink --- , Republic of South Africa ElizabethA. Davies --- , EnglandThe effect of Ca:K ratios and B nutrition was investigated using tobacco and cotton grown in Mitcherlich pots with sand. A nutrient solution with three different ratios of Ca:K and two boron levels was used. Treatments were arranged factorially (3... -
Factors affecting fruit quality and shelf life of Bon Chretien pears
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.J. van Zyl --- , Republic of South Africa J.M. Olivier --- Deciduous Fruit Board, Republic of South AfricaBon Chretien pears for canning and the fresh market are grown under various climatic conditions in South Africa. The major orchard factor affecting the shelf life of the fruit after storage seems to be the number of days between full-... -
The influence of different P, NH+ 4 and NO− 3 supply levels on the yield and P and Ca relationships in wheat
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.S. Claassens --- Department Soil Science and Plant Nutrition, Republic of South Africa W.J. Fölscher --- Department Soil Science and Plant Nutrition, Republic of South AfricaIn a water culture experiment with wheat, the influence on growth and nutrient uptake of varying the P supply from 0,02 to 5 mmol H2PO4 − dm−3 and the NH4 +:NO3 − ratio from 0:15 to 12:3, with a Hoagland... -
Growth and nutrient content of soybeans in relation to solution calcium and aluminium
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.D. Noble --- Department of Crop Science, Republic of South Africa M.E. Sumner --- Department of Agronomy, United States of AmericaAluminium (Al) is a major component of most soils and is a limiting factor to sustained crop production in many regions. The amelioration of Al toxicity is of theoretical as well as practical interest in our understanding of mechanisms of... -
Application of the calcium-calcichrome colour reaction to the spectrophotometric determination of calcium in plant material
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Xing-Chu Qiu --- , People's Republic of China Ying-Quan Zhu --- , People's Republic of ChinaA highly selective spectrophotometric method has been developed for the determination of micro-amounts of calcium in plant material with calcichrome as the colour reagent. The absorption maximum of the complex is at 520 nm. At this wavelength, Beer's law is... -
Concentration, accumulation and uptake rate of macro-nutrients by winter wheat under irrigation
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.C. du Preez --- Department of Soil Science, Republic of South Africa A. T.P. Bennie --- Department of Soil Science, Republic of South AfricaThe objective of this study was to obtain information on the nutrient uptake patterns of winter wheat (Triticum aestivum L.) grown under normal irrigation farming conditions. Except for irrigation scheduling, 13 farmers were allowed to follow their normal farming practices... -
Optimizing MCPA (K-salt) activity with adjuvants
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: B.L. de Villiers --- , Republic of South Africa H.A. Smit --- , Republic of South Africa R.C. Lindeque --- , Republic of South Africa J.J. Smit --- , Republic of South AfricaMCPA [2-methyl-4-chloro phenoxy acetic acid] is applied with various water sources containing antagonistic salts. It is applied without an adjuvant but is often mixed with bromoxynil for a broader spectrum of weeds. MCPA (K-salt) was applied in carriers containing calcium... -
Number and concentration of calcium nitrate plus Kelpak® sprays for control of bitter pit in 'Braeburn5 apple fruit
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M. North --- , J. Wooldridge --- ,In a spray trial to test the effects of calcium nitrate and a kelp extract (Kelpak®), fruit calcium (Ca) concentrations in ‘Braeburn’ apples peaked between 7.6 and 9.5 mg 100 g−1 fresh mass (FM) on 19 December 2000, then declined... -
The effect of boron levels in nutrient solutions on fruit production and quality of greenhouse tomatoes
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.N. Smit --- Department of Agronomy, Republic of South Africa N. J.J. Combrink --- Department of Agronomy, Republic of South AfricaInsufficient fruit set of tomatoes owing to poor pollination in low cost greenhouses is a problem in South Africa, as bumblebee pollinators may not be imported. Since sub-optimum boron (B) levels may also contribute to fruit set problems, this aspect... -
Reaction of potatoes to calcium and phosphate levels as affected by wind
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R. Barnard --- Department of Agronomy, Republic of South Africa N. J.J. Combrink --- Department of Agronomy, Republic of South AfricaIn an attempt to increase the number of mini tubers produced per potato plant, the effect of calcium and phosphorus nutrition was investigated. It is believed that high phosphorus (P) and low calcium (Ca) levels stimulate tuberization. Three nutrient solution... -
Potato mini tuber production affected by a short-term calcium deficiency
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R. Barnard --- Department of Agronomy, Republic of South Africa N. J.J. Combrink --- Department of Agronomy, Republic of South AfricaIt was previously reported that tuber initiation is restricted in soil-less production systems owing to a lack of mechanical resistance and that a low-pH shock treatment over a 10-h period alleviated this problem. Tuber initiation was investigated under soil-less conditions... -
Comparison of osmopriming and seed coating with calcium salts for green bean performance under field conditions. I. Cotyledonal cracking
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: T.G. Mazibuko --- , A.T. Modi --- ,Cotyledonal cracking is a physiological disorder, which appears as one or a few transverse fissures across legume seed cotyledons early during seed germination or seedling emergence. The fissures hinder translocation of nutrients to the developing seedling and cause stunted seedling... -
Comparison of osmopriming and seed coating with calcium salts for green bean performance under field conditions. II. Stand establishment, chlorophyll fluorescence and yield
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: T.G. Mazibuko --- School of Agricultural Sciences & Agribusiness, Crop Science Discipline, A.T. Modi --- School of Agricultural Sciences & Agribusiness, Crop Science Discipline,Seed coating is commonly used to supply fungicides and micronutrients to enhance seed quality. The primary reason for using mineral elements in seed priming is to regulate water absorption. Osmopriming and seed coating were compared for their effect on crop... -
Effect of adjuvants on apple fruit and leaf calcium and nitrogen concentrations at three fruit growth stages
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M. North --- , J. Wooldridge --- ,In a field trial, 0.006% v/v Agral-90® and four alternative adjuvants were evaluated to determine their effects on calcium (Ca) and nitrogen (N) uptake by leaves and fruit of ‘Golden Delicious’ apple from 0.45% m/v calcium nitrate sprays. No bitter... -
Ameliorative effects of calcium on growth and mineral uptake of salt-stressed amaranth
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: E.N. Ornami --- Department of Plant Production and Soil Sciences, South Africa P.S. Hammes --- Department of Plant Production and Soil Sciences, South AfricaThe detrimental effects of salinity stress in plants may be ameliorated by calcium. However, little is known concerning the efficacy of different calcium sources, especially in amaranth. Two amaranth genotypes (Amaranthus tricolor and A. cruentus) were grown in a greenhouse... -
The effects of strategic nitrogen fertiliser application during the cool season on perennial ryegrass-white clover pastures in the Western Cape Province 4. Selected nutritive characteristics and mineral content
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Labuschagne --- , South Africa M.B. Hardy --- Department of Agriculture Western Cape, South Africa G.A. Agenbag --- , South AfricaThe influence of a single application of fertiliser N (0, 50, 100 and 150 kg N ha−1) applied in either autumn, early winter, late winter, early spring or late spring on selected nutritive and mineral parameters of a perennial ryegrass-white... -
Effects of sugar cane (Saccharum hybrid sp.) cropping on soil acidity and exchangeable base status in Mauritius
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L. R. Ng Cheong --- , Mauritius K. F. Ng Kee Kwong --- Department of Soil, Crop and Climate Sciences, South Africa C. C. Du Preez --- , MauritiusContinuous sugar cane cropping commonly leads to soil acidification. Such an effect can be attributed to N fertilization and to leaching and removal of exchangeable bases. A study was conducted on the five zonal soils of Mauritius to ascertain whether... -
The efficacy of 6-benzyladenine, gibberellins4+7 and prohexadione-calcium to increase fruit size in ‘Forelle’ and ‘Abate Fetel’ pear
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Carlien Dreyer --- Department of Horticultural Science, South Africa Karen I Theron --- Department of Horticultural Science, South AfricaFruit size is an important marketing and quality parameter and has a significant effect on the economic value of fruit. The application of synthetic cytokinins are believed to enhance fruit size by stimulating and extending the cell division stage in... -
Seasonal nutrient fluctuation in selected plant species in the Kalahari
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: FH Stapelberg MW van Rooyen J du P BothmaSeasonal changes in crude protein, phosphorus and calcium contents of five common plant species in the south-western Kalahari were investigated. Three species that are browsed by springbok (Acacia erioloba, Grewia flava and Rhigozum trichotomum) and two grass species (Schmidtia kalahariensis... -
HYPERCALCAEMIA: A finding not to be taken too lightly
Item type: Journal Article • Journal: South African Family Practice • Authors: EK Venter --- Pretoria Academic Hospital, F Naudé --- Pretoria Academic Hospital, BJ Meyer --- Pretoria Academic Hospital, -
Cardiovascular risk assessment
Item type: Journal Article • Journal: South African Family Practice • Authors: DJ Blom --- Division of Lipidology, Department of Medicine, South AfricaCardiovascular disease remains the leading cause of mortality in the Westernised world. Lifestyle changes and drug therapy can reduce cardiovascular risk. Many interventions such as lipid-lowering therapy reduce relative risk to the same extent irrespective of baseline risk, but the... -
The role of nutrient solution composition on the uptake of nutrients, growth and vase life of tulips grown hydroponically under South African conditions
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Geline Derbyshire --- Department of Agronomy, South Africa Eleanor W Hoffman --- Department of Horticultural Sciences, South Africa Estelle Kempen --- Department of Agronomy, South AfricaAn understanding and optimisation of the key agronomical aspects required for successful hydroponic cultivation of cut tulips in South Africa, a warm production region, is essential to unlock its commercial potential. In this study the effect of nutrient solution composition,... -
Calcium improves gerbera (Gerbera hybrida) vase life
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Nic JJ Combrink --- Department of Agronomy, Faculty of AgriSciences, South AfricaThe vase life of Gerbera hybrida cut flowers is about two weeks. To prevent wilting, hypochlorite is widely used in vase water to control micro-organisms that may block xylem cells and restrict water uptake. In this study, three levels of... -
Effects of egg shell meal on the performance and haematology of layers and their egg quality
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Uchele Okpanachi --- , Nigeria Khalid Aliyu Yusuf --- , Nigeria Maryann Kehinde Ikubaje --- , Nigeria Gift Cincin Amaje Okpanachi --- , NigeriaIn an attempt to achieve Sustainable Development Goals numbers one and two, eggshell meal was incorporated into layers diets to replace bone meal. Seventy-two point of lay birds were utilized in a nine-week experiment. Four experimental diets were formulated consisting... -
Bone health in patients undergoing surgery for primary hyperparathyroidism at Tygerberg Hospital, Cape Town, South Africa
Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: M Budge --- , W Conradie --- , K Beviss-Challinor --- , L Martin --- , M Conradie --- , A Coetzee --- , -
Comparison of calcium concentration in scales and vertebral column of a cyprinid from calcium-limited environments in the Lake Victoria Basin, Uganda
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: WA Nesbitt --- , Canada SB Clarke --- , Canada LJ Chapman --- , CanadaDespite dramatic differences in calcium concentrations within aquatic systems, very few studies have explored the relationships between ambient calcium concentration and the calcium concentration of resident fish under natural conditions. This study compares calcium concentration in the water to that... -
Effects of diet on the systematic utility of the tortoise carapace
Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: Justin Gerlach --- University Museum of Zoology Cambridge, U.K.The main character used in identifying species of Chelonia is the carapace. The taxonomy of several terrestrial tortoise genera remains highly disputed, due in part to a limited knowledge of the limits of variation in many populations. For taxa where... -
Prevalence of osteoporosis and factors associated with bone density in HIV-positive kidney transplant candidates and recipients from an HIV-positive donor
Item type: Journal Article • Journal: South African Journal of Clinical Nutrition • Authors: CJ Martin --- University of KwaZulu-Natal, South Africa T Gwetu --- Department of Obstetrics and Gynaecology, Grey’s Hospital, South Africa D Labadarios --- Stellenbosch University, South Africa E Muller --- University of Stellenbosch, South Africa FJ Veldman --- , South Africa C Ellis --- University of Pretoria, South Africa SM Kassier --- University of KwaZulu-Natal, South Africa -
Short-term outcomes in post-parathyroidectomy patients at Tygerberg Hospital
Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: R Pargner --- Tygerberg Hospital, Stellenbosch University, South Africa A Coetzee --- Tygerberg Hospital, Stellenbosch University, South Africa L Martin --- Tygerberg Hospital, Stellenbosch University, South Africa C Burger --- Stellenbosch University and Tygerberg Hospital, South Africa W Conradie --- Tygerberg Hospital, Stellenbosch University, South Africa