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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... -
The relationship between subsoil colour and degree of wetness in a suite of soils in the Grabouw district, Western Cape I. Characterization of colour-defined horizons
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.W. van Huyssteen --- , South Africa F. Ellis --- , South AfricaSoil colour is an easily identifiable property that is invariably used as a parameter in all soil classification systems including the system used in South Africa. To test the hypothesis that soil colour is a reflection of the soil water... -
The relationship between subsoil colour and degree of wetness in a suite of soils in the Grabouw district, Western Cape II. Predicting duration of water saturation and evaluation of colour definitions for colour-defined horizons
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.W. van Huyssteen --- , South Africa F. Ellis --- Faculty of Forestry, South Africa J. J.N. Lambrechts --- Faculty of Agricultural Sciences, South AfricaExisting colour indices were evaluated to determine their correlation with duration of water saturation, for a hydrosequence in the Grabouw district, Western Cape. Correlation coefficients ranged between 0.31 and 0.63. More simple colour indices were developed. Dry soil colour is... -
Investigation of the suitability of Western and Southern Cape wheat flour for production of traditional South African steamed bread
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M. Manley --- Department of Food Science, Republic of South Africa M.M. Nel --- Department of Agronomy and Pastures, Republic of South AfricaDue to a lack of electrical ovens, it is often found that in the households of the lower-income communities, a home-made steamed bread is prepared in a saucepan on a gas cooker or an open fire. The requirements of flour... -
Exogenously applied ethylene reduces the cold requirement for ripening of pears (Pyrus communis L.) cv. Forelle
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P.G. du Toit --- Department of Horticultural Science, South Africa G. Jacobs --- Department of Horticultural Science, South Africa M. Huysamer --- Department of Horticultural Science, South Africa D.M. Holcroft --- Department of Horticultural Science, South Africa‘Forelle’ pears harvested at commercial maturity were treated with ethylene at 0, 10 or 100 μl 1−1 for 24 hours at 20°G before being stored at-0.5°Cfor 12 weeks. Periodic sampling of the fruit showed that both ethylene treatments significantly hastened... -
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... -
Effect of timing and method of nitrogen application on rind colour, fruit size, internal fruit quality and yield of ‘Mihowase Satsuma’ mandarin (Citrus unshiu Marc.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: F.N. Mudau --- Department of Horticultural Science, Republic of South Africa S. Tuwana --- Department of Horticultural Science, Republic of South Africa K.I. Theron --- Department of Horticultural Science, Republic of South Africa E. Rabe --- Department of Horticultural Science, Republic of South AfricaEarly rind colour development is a major problem in the production of early-maturing ‘Mihowase Satsuma’ mandarin (Citrus unshiu Marc.) in the Western Cape, South Africa. The effect of different combinations of soil- applied limestone ammonium nitrate and foliar-applied low-biuret urea... -
Interpretation of digital soil photographs using spatial analysis: I. Methodology
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.W. van Huyssteen --- Department of Soil, Crop and Climate Sciences, South Africa P. A.L. le Roux --- Department of Soil, Crop and Climate Sciences, South Africa M. Hensley --- Department of Soil, Crop and Climate Sciences, South AfricaSystems for the evaluation of soil wetness use soil colour extensively. The determination of soil colour normally relies on the user's perception of colour and usually employs a colour matching system, e.g. Munsell Soil Color Charts. The South African soil... -
Interpretation of digital soil photographs using spatial analysis: II. Application
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.W. van Huyssteen --- Department of Soil, Crop and Climate Sciences, South Africa P. A.L. le Roux --- Department of Soil, Crop and Climate Sciences, South Africa M. Hensley --- Department of Soil, Crop and Climate Sciences, South AfricaColour variation in digital photographs of soils was quantified and classified meaningfully, using ArcView Spatial Analyst. This procedure holds great promise for the unbiased and quantitative determination of soil colour properties and statistical correlation with related soil hydrological conditions. The... -
Relationship between ergot and grain mould development in sorghum (Sorghum bicolor (L.) Moench)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G. Tarekegn --- Centre for Plant Health Management, Department of Plant Sciences, South Africa N.W. McLaren --- Centre for Plant Health Management, Department of Plant Sciences, South Africa W.J. Swart --- Centre for Plant Health Management, Department of Plant Sciences, South AfricaA greenhouse experiment was conducted to determine the influence of sorghum ergot on the incidence of grain mould pathogens and on damage to sorghum grains. Grain mould pathogens used were Curvularia lunata, Fusarium subglutinans and Phoma sorghina. Inoculation with the... -
Frodo and Darius: South African potato cultivars with good processing quality
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.M. Steyn --- Department of Plant Production and Soil Science, South Africa E.B. Geremew --- Department of Plant Production and Soil Science, South Africa J.G. Annandale --- Department of Plant Production and Soil Science, South Africa P.J. Steyn --- , South AfricaTwo newly released South African potato cultivars, Frodo and Darius, were compared with two foreign processing cultivars, Pentland Dell and Shepody. The cultivars were grown under sprinkler irrigation and evaluated for external and internal tuber characteristics and processing quality. The... -
Elucidation of seasonal pigmentation patterns in the involucral leaves of Leucadendron ‘Safari Sunset’
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Michael Schmeisser --- Department of Horticultural Science, South Africa Gerard J Jacobs --- Department of Horticultural Science, South Africa Willem J Steyn --- Department of Horticultural Science, South AfricaThis study investigates seasonal pigmentation patterns found in the involucral leaves of Leucadendron ‘Safari Sunset’, with the long-term aim of colour manipulation. Treatments comprised deconed shoots and shoots in which the opening of the flower head was physically prevented. During... -
‘Coloured’ Boys Talk: Constructing Heterosexual Masculinities in a Working Class High School Context
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Bronwynne Anderson --- University of KwaZulu-Natal,This article presents the results of a year-long ethnographic study of 13 ‘Coloured’, working class, high school boys aged 14–17 in KwaZulu-Natal, South Africa. Data derived using participant observation and semi-structured in-depth interviews. Social constructionist perspectives were used as a... -
Vertex coverings by coloured induced graphs — Frames and Umbrellas
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Wayne Goddard MichaelA. HenningA graph G homogeneously embeds in a graph H if for every vertex x of G and every vertex y of H there is an induced copy of G in H with x at y. The graph G uniformly embeds... -
Is caudal fin colour in tigerfish Hydrocynus vittatus a sex or population trait?
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Soekoe --- Centre for Aquatic Research, Department of Zoology, South Africa FH van der Bank --- African Centre for DNA Barcoding, Department of Zoology, South Africa NJ Smit --- Water Research Group (Ecology), Unit for Environmental Sciences and Management, Potchefstroom Campus, South AfricaTigerfish caudal fin colours vary from yellow to red, with distinct dissimilarities previously noted. To understand these colour differences, tigerfish were collected during 2008 to 2010 from four southern African populations in the Upper Zambezi River (ZAM), Okavango Delta (OKA),... -
Rapid assessment of tissue nitrogen in cultivated Gracilaria gracilis (Rhodophyta) and Ulva lactuca (Chlorophyta)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DV Robertson-Andersson --- Botany Department, South Africa DT Wilson --- Botany Department, South Africa JJ Bolton --- Botany Department, South Africa RJ Anderson --- Botany Department, South Africa GW Maneveldt --- Department of Biodiversity and Conservation Biology, South AfricaTissue nitrogen content and thallus colour were quantified using a rapid assessment method based on the Pantone® matt uncoated formula guide for raft-cultivated Gracilaria gracilis Steentoft, Irvine ef Farnham at Saldanha Bay and tank-cultivated Ulva lactuca Linnaeus at Jacobsbaai in... -
Age, Gender and Social Class Influences on Skin Colour Preferences Among Mozambican Children
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Germano Vera Cruz --- University of Toulouse II, FranceThis study examined skin colour preferences among Mozambican children (N = 500; male = 48% and females = 52%; middle-high SES = 48% and low SES = 52%; mean age = 7.34 and SD = 1.80). The children selected preferred... -
Phylogeography and genetic diversity of Psammophis schokari (Serpentes) in North Africa based on mitochondrial DNA sequences
Item type: Journal Article • Journal: African Zoology • Authors: C. Rato --- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Portugal J. C. Brito --- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Portugal M. A. Carretero --- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Portugal S. Larbes --- Département de Biologie, Algeria B. Shacham --- Department of Evolution, Systematics & Ecology, Israel D. J. Harris --- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, PortugalThe snake Psammophis schokari has a widespread distribution across North Africa, and in Morocco/Western Sahara is represented by three different morphotypes: striped, unicoloured and the Western-Sahara morph. ND4 mitochondrial DNA sequences from 28 specimens comprising 20 P. shokari, two P... -
A study of moult-site fidelity in Egyptian geese, Alopochen aegyptiaca, in South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Mduduzi Ndlovu --- Organisation for Tropical Studies/School of Animal, Plant and Environmental Sciences, University of Witwatersrand, South Africa Graeme S. Cumming --- Percy FitzPatrick Institute, DST/NRF Centre of Excellence, University of Cape Town, South Africa Philip A. R. Hockey --- Percy FitzPatrick Institute, DST/NRF Centre of Excellence, University of Cape Town, South Africa Mbongeni D. Nkosi --- Percy FitzPatrick Institute, DST/NRF Centre of Excellence, University of Cape Town, South Africa Gregory L. Mutumi --- Percy FitzPatrick Institute, DST/NRF Centre of Excellence, University of Cape Town, South AfricaLittle is known about moult and moult-site fidelity of African waterfowl. Satellite telemetry and uniquely engraved colour-rings were used to study moult-site fidelity of Egyptian geese marked at two sites in South Africa – Barberspan in the summer-rainfall region and... -
Cattle and cattle colour terminology in South Africa
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Louis J Louwrens --- Department of African Languages, Elsabé Taljard --- Department of African Languages,A comparison between cattle colour terminology found in the Khoikhoi languages and that found in South African Bantu languages brings noticeable similarities to light, leading to the assumption that both the cattle and the terms used to describe their characteristic... -
The burden of responsibility and the breakdown of traditional paternalism on farms in the Western Cape
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: Handri Walters --- Department of Sociology and Social Anthropology, South AfricaThe transition that followed the 1994 democratic election in South Africa brought with it a host of progressive legislation aimed at the provision of a secure environment for those previously marginalised. The Extension of Security of Tenure Act (ESTA) (1997)... -
Transvaginal colour Doppler ultrasound in predicting response to chemoradiation in patients with carcinoma of the cervix
Item type: Journal Article • Journal: Southern African Journal of Gynaecological Oncology • Authors: Mishu Mangla --- SMS Medical College, India Deepak Singla --- Department of Anaesthesia,Background: The objective of the study was to evaluate the potential role of transvaginal colour Doppler ultrasound (TVCDUS) in predicting response to chemoradiotherapy in patients with locally advanced cervical cancer. -
The invasive Asian green mussel Perna viridis in South Africa: all that is green is not viridis
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JM Micklem --- Centre for Invasion Biology, Department of Biological Sciences, South Africa CL Griffiths --- Centre for Invasion Biology, Department of Biological Sciences, South Africa N Ntuli --- South African Institute for Aquatic Biodiversity, South Africa M Mwale --- South African Institute for Aquatic Biodiversity, South AfricaThe Asian green mussel Perna viridis is an invasive Indo-Pacific species recently reported from South African harbours. To verify the invasion, a phylogenetic (and morphological) analysis of green-shelled mussels (n = 39), found in six South African harbours, was conducted... -
The potential of NIRs as a non-destructive post-harvest quality assessment tool for ‘Triumph’ persimmon fruit
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Pesanai Zanamwe --- Department of Botany and Biotechnology, South AfricaThe potential of near-infrared spectroscopy (NIRs) as an alternative non-destructive post-harvest quality assessment tool for ‘Triumph’ persimmon fruit was assessed. Fruits were harvested at four stages of maturity and each stage was replicated four times. Fruit quality was assessed at... -
Two cases of probable hybridisation between the pufferfishes Arothron meleagris (Anonymous 1798) and A. nigropunctatus (Bloch and Schneider 1801) on a fringing reef at Réunion Island
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P Bourjon --- Les Sentinelles du Récif, réseau d’observateurs volontaires de la Réserve Naturelle Marine de La Réunion [‘Sentinels of the Reef’, Volunteer Observers Network of the Réunion Marine Park] (GIP–RNMR), Réunion Island B Chanet --- Institut de Systématique, FranceTwo individuals displaying mixed features of the colour patterns distinctive of Arothron meleagris and A. nigropunctatus were observed on the fringing reef at Réunion Island, between September 2012 and August 2013. Because many hybrid fish have been first identified through... -
Carotenoid-based plumage pigmentation and concentration as a function of sex and habitat type in the Yellow-breasted Boubou Laniarius atroflavus
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: S Temidayo Osinubi --- School of Biological Sciences, New Zealand Kevin J McGraw --- School of Life Sciences, USA Ulf Ottosson --- AP Leventis Ornithological Research Institute, University of Jos, Nigeria Jennifer A Brown --- School of Mathematics and Statistics, New Zealand James V Briskie --- School of Biological Sciences, New Zealand Hazel M Chapman --- School of Biological Sciences, New ZealandThe study of avian integumentary colouration can offer insight into dietary and metabolic processes as well as fitness in focal species. Yet, we know relatively less about the system of feather colouration in African birds in comparison to Europe, North... -
Mc1r genotype and plumage colouration in highly polymorphic jackal buzzards, Buteo rufofuscus
Item type: Journal Article • Journal: African Zoology • Authors: Sophia Bam --- School of Life Sciences, South Africa Lorinda Hart --- School of Life Sciences, South Africa Sandi Willows-Munro --- School of Life Sciences, South AfricaEvolution is driven by natural selection acting on variable phenotypic traits. Understanding the molecular basis of those traits is crucial for elucidating the mechanisms of natural selection. The southern African jackal buzzard (Buteo rufofuscus) displays extreme plumage colour polymorphism, with... -
Eucalypt susceptibility towards the invasive Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) in South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Samantha J Bush --- , South Africa Bernard Slippers --- , South Africa Brett P Hurley --- , South AfricaGlycaspis brimblecombei (Hemiptera: Aphalaridae) is a eucalypt feeder native to Australia. Infestations of G. brimblecombei can cause leaf wilt, dieback and death in weak or severely infested plants. In many countries where G. brimblecombei has been introduced, patterns of susceptibility... -
Are there long-term temporal trends of size composition and the length– weight relationship? Results for chokka squid Loligo reynaudii during the peak spawning season off the south coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MR Lipiński --- , South Africa MA Mmethi --- , South Africa D Yemane --- , South Africa J Githaiga-Mwicigi --- , South Africa WHH Sauer --- , South AfricaTemporal trends in the size composition (length frequency) and length–weight (L–W) relationship of chokka squid Loligo reynaudii on the south coast of South Africa were assessed over periods spanning 22 years: length frequencies from 1996 to 2017 (with 15 years... -
New records and a notable observation of potentially predator-avoiding amplectic behaviour in Boophis erythrodactylus from Madagascar
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Robin Kurian Abraham --- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, United States Carl Richard Hutter --- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, United StatesThe Red-fingered Bright-eyed Frog Boophis erythrodactylus is an endemic, range-restricted arboreal frog found only in the eastern rainforests of Madagascar. We report new localities for this species, along with locality records for its sister species B. tasymena, including localities where... -
New data on the South African acontine skink Typhlosaurus lomii Haacke 1986 (Squamata: Scincidae)
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: AaronM. Bauer --- Villanova University, USA Victoria Schneider --- Villanova University, USA Trip Lamb --- East Carolina University, USA PaulE. Moler --- Florida Game and Fresh Water Fish Commission , USA RandallD. Babb --- , USA -
Shell characteristics and sexual dimorphism in the Namaqualand speckled padloper, Homopus signatus signatus
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: VictorJ.T. Loehr --- University of the Western Cape, South Africa BrianT. Henen --- University of the Western Cape, South Africa MargarethaD. Hofmeyr --- University of the Western Cape, South AfricaThere is little quantitative information regarding the two subspecies of the world's smallest tortoise, Homopus signatus. To help characterise the northern subspecies H. s. signatus and evaluate the development of shell size and colour patterns, we measured shell characteristics of... -
New range extensions for Dasypeltis atra Sternfeld in Tanzania (Serpentes : Colubridae), with a review of the distribution of colour phases
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: DonaldG. Broadley --- Biodiversity Foundation for Africa, Zimbabwe MichaelF. Bates --- National Museum, South AfricaFour Tanzanian specimens of the patterned phase of Dasypeltis atra represent range extensions into savanna areas. One of these specimens, from Ibaya Camp in Mkomazi Game Reserve, extends the species’ range by about 100 km to the south‐east from Mount... -
Testing the thermal melanism hypothesis for Cape Cobras (Naja nivea) using community science photographic data
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Jody M Barends --- University of Johannesburg, South Africa Kim J Scholtz --- University of the Western Cape, South AfricaAnimal colour is a highly adaptive phenotypic trait that can respond to several selection pressures, including those facilitated by variations in climate. The thermal melanism hypothesis predicts that for ectotherms, selection for darker phenotypes should be highest in cooler areas... -
On uniquely packable trees
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: A. Alochukwu --- Albany State University, USA M. Dorfling --- University of Johannesburg, South Africa E. Jonck --- University of the Witwatersrand, South AfricaAn i-packing in a graph G is a set of vertices that are pairwise at distance more than i. A packing colouring of G is a partition X = {X 1, X 2, . . . , X k... -
Patterned, plain, and in-between: An assessment of ecogeographic divergence between colour pattern morphs of the common egg-eater Dasypeltis scabra
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Jody M. Barends --- University of Johannesburg, South Africa Ielhaam Bassier --- University of the Western Cape, South Africa Emma E. Buckley --- University of the Western Cape, South Africa Cora S. Stobie --- National Museum, South Africa Michael F. Bates --- National Museum, South AfricaIntraspecific variation in colour patterns may reflect adaptive responses to local environmental regimes that favour selection of different trade-offs between visual communication, thermoregulation, and anti-predatory functions. Understanding the drivers of colour pattern variation within species can therefore provide valuable insights... -
Aspirations and meanings of lighter skin tone in the African context: A rapid review
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Sikelelwa Ntsokota --- North-West University, South Africa Lelanie Malan --- North-West University, South Africa Esmé van Rensburg --- North-West University, South Africa Werner de Klerk --- North-West University, South AfricaAcross cultures, skin tone is associated with social impressions and outcomes, but the meanings and implications of these associations has not garnered clear research evidence. This rapid review aimed to aggregate the evidence regarding the ascribed meanings and implications of... -
Colorimetric changes in two radial positions caused by wood-decaying fungi in wood of seven eucalypt species
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Pedro Nicó de Medeiros Neto --- Federal University of Campina Grande, Brazil Juarez Benigno Paes --- Federal University of Espírito Santo, Brazil João Gabriel Missia da Silva --- Federal University of Espírito Santo, Brazil Fabricio Gomes Gonçalves --- Federal University of Espírito Santo, Brazil Daniela Minini --- Federal University of Paraná, Brazil Libânia da Silva Ribeiro --- Federal University of Campina Grande, Brazil Fernanda Dalfiôr Maffioletti --- Federal University of Espírito Santo, BrazilThis research aimed to determine the colorimetric alterations of the wood of seven eucalypt species caused by fungal decay in two positions in the pith–bark direction (median heartwood and transition region, containing the heartwood and sapwood), during wood exposure to...