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Growth patterns of Italian ryegrass cultivars established in different seasons
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: D.C.W. Goodenough --- Department of Agriculture (Natal Region), C.I. Macdonald --- Department of Agriculture (Natal Region), A.R.J. Morrison --- Department of Agriculture (Natal Region),A comparison is made between various Italian ryegrass cultivars established under irrigation on a well‐drained upland site during the traditional autumn months, with plantings of the same cultivars at other times of the year. -
The persistence in soil and phytotoxicity on dry beans of alachlor and metolachlor as affected by climatic factors
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: E. van Rensburg --- , L.P. van Dyk --- ,The persistence of alachlor (2-chloro-2′, 6′-diethyl-N-methoxymethylacetanilide) and metolachlor [2-chloro-6′-ethyl-N-(2-methoxy-1-methylethyl)acet-O-toluidide] in soil was determined over an 80-day period at temperatures ranging from 5 to 50°C. Soils were maintained at either 50 or 100% of field capacity. The herbicides were less persistent... -
Quantitative bioassays for monitoring the dissipation of atrazine in soil
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Department of Plant Production, Republic of South Africa P.C. Nel --- Department of Plant Production, Republic of South AfricaA simple bioassay technique was used to study the residual activity of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] applied at 0.25 kg ai ha−1 at different depths in a sandy clay loam (22% clay; 0.31% organic C) soil. Oats (Avena sativa L. cv. SWK001)... -
Residual effect of atrazine on field-grown dry beans and sunflower
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Department of Plant Production and Soil Science, Republic of South AfricaThe applicability of fixed recropping intervals for crops that are sensitive to atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-striazine) was assessed. Atrazine carry-over was monitored 12 and 24 months after its application at six different rates to maize (Zea mays L.) grown in eight trials... -
Maize cultivars differ in tolerance to imazethapyr
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L.J. van Wyk --- Department of Plant Production and Soil Science, Republic of South Africa C.F. Reinhardt --- Department of Plant Production and Soil Science, Republic of South AfricaThe low tolerance of maize (Zea mays L.) to imazethapyr ((±)-2-[4,5-dihydro-4 methyl-4-(1 -methylethyl)-5-oxo 1H-imidazol-2-yl]-5-ethyl-3-pyridinecarboxylic acid) resulted in extensive crop damage in 1992/93 due to residue carry-over from resistant soybean (Glycine max L.). Pot experiments were conducted to assess the role... -
Persistence of the pesticidal Bacillus thuringiensis protein expressed in Bt maize plant materials in two soils of the Central Eastern Cape, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: P. Muchaonyerwa --- Department of Agronomy, South Africa S.M. Waladde --- Department of Zoology, South AfricaEnvironmental effects of genetically modified plants are not yet fully understood. Experiments were conducted to determine relative amounts of the bioactive Bt protein in roots, leaves and stems of Bt maize and persistence of the protein in two soil forms... -
Influence of grazing frequency and intensity on aerial and reproductive tillering in Lolium perenne L. under subtropical conditions
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: F.R. McKenzie --- Department of Grassland Science, Republic of South AfricaReproductive and aerial tillering dynamics in Lolium perenne L. (perennial ryegrass) was monitored for two years under grazing. Reproductive tillers were observed from winter (June) to midsummer (February) with the main period of initiation occurring in spring to early summer... -
A note on the diet and feeding of Chrysaora hysoscella in Walvis Bay Lagoon, Namibia, during September 2003
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BA Flynn MJ GibbonsThe diet of Chrysaora hysoscella was investigated from 55 specimens caught near the surface throughout 24h in Walvis Bay Lagoon, Namibia, during September 2003. The diet was diverse, ranging from dinoflagellates to carideans, and included abundant benthic species (adults and... -
Estimating scavenger and search bias for collision fatality surveys of large birds on power lines in the Karoo, South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Maurice Schutgens --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa Jessica M Shaw --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South Africa Peter G Ryan --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute of African Ornithology, South AfricaBird collision mortality associated with power lines is a global conservation challenge, but periodic carcass counts along power lines underestimate actual mortality because of survey biases. We conducted a scavenger trial over 90 days and three observer detection trials after... -
Recent evidence on the persistence of fund performance – A note
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: D Bradfield --- Department of Statistical Sciences, J Swartz --- University of Cape Town,This note highlights recent evidence on the persistence of fund performance in South Africa, throwing new light on the 1985–1995 study conducted by Meyer (1997). Our analysis on the persistence of South African fund performance is based on the General... -
Are historic growth patterns an indication of future growth patterns?
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: B W Steyn --- Department of Accountancy, W D Hamman --- Graduate School of Business, University of Stellenbosch,Over the last decade or two, much has been made of high and exceptionally high growth rates. In this paper, sales growth rates for industrial companies listed in South Africa are examined for the period 1974 to 2002. -
Recent evidence on the persistence of fund performance—A note
Item type: Journal Article • Journal: South African Journal of Accounting Research • Authors: D Bradfield --- Quantitative Research, Cadiz Holdings, J Swartz --- University of Cape Town,This note highlights recent evidence on the persistence of fund performance in South Africa, throwing new light on the 1985–1995 study conducted by Meyer (1997). Our analysis on the persistence of South African fund performance is based on the General... -
The impact of the Eurozone sovereign debt crisis on bond fund performance persistence: Evidence from a small market
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Paulo Leite --- Applied Management Research Unit (UNIAG), Portugal Orlando Faria --- Medicavado Group – Insurance Company, Portugal Manuel Rocha Armada --- NIPE – School of Economics and Management, PortugalWe evaluate the impact of the Eurozone sovereign debt crisis on the performance and performance persistence of a survivorship bias-free sample of bond funds from a small market, identified as one of the most affected by this event, during the... -
Trait variations in 28-year-old teak (Tectona grandis) provenance field trials in Ghana, West Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Stephen Adu-Bredu --- CSIR-Forestry Research Institute of Ghana, Ghana Daniel A Ofori --- CSIR-Forestry Research Institute of Ghana, Ghana Anders Ræbild --- Department of Geosciences and Natural Resource Management, Faculty of Science, Denmark Jon K Hansen --- Department of Geosciences and Natural Resource Management, Faculty of Science, Denmark Appolinaire Koffi --- Société de Développement defs Forêts (SODEFOR), Côte d’Ivoire Philipp Vigneron --- CIRAD, Forest Department, Research Unit 39, Diversity and Breeding of Forest Tree Species, France Erik D Kjær --- Department of Geosciences and Natural Resource Management, Faculty of Science, DenmarkStem straightness, axis persistence, presence/absence of protuberant buds and epicormics, diameter and height have profound influence on timber quality and volume of teak (Tectona grandis). Provenance trials of teak were established in the 1970s in Ghana, as part of the... -
Impacts of a concentrated solar power trough facility on birds and other wildlife in South Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Corey Jeal --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Vonica Perold --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South Africa Samantha Ralston-Paton --- BirdLife South Africa, South Africa Peter G Ryan --- FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, South AfricaThis study assesses bird and wildlife mortality and changes in bird species communities at a 50 MW utility-scale concentrated solar power parabolic trough facility in South Africa. The facility was searched for evidence of large vertebrate mortalities over three months... -
Does the choice of fund performance measure matter?
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Christopher Adcock --- School of Finance and Management, UK Nelson Areal --- NIPE Research Centre, School of Economics and Management, Portugal Maria Céu Cortez --- NIPE Research Centre, School of Economics and Management, Portugal Benilde Oliveira --- School of Economics and Management, Portugal Florinda Silva --- NIPE Research Centre, School of Economics and Management, PortugalThis paper investigates whether investment strategies using rankings based on different portfolio performance measures lead to different future abnormal returns. A set of 13 commonly used risk-adjusted performance measures is applied to a dataset of US equity mutual funds over... -
Farmer knowledge, attitude and practices on sorghum allelopathy in five sorghum producing districts of Zimbabwe
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H Tibugari --- , South Africa C Chiduza --- , South Africa AB Mashingaidze --- , ZimbabweLack of knowledge about allelopathy technology may be a barrier to the adoption of allelopathy by farmers. A questionnaire survey together with physical weed sampling in farmers’ fields were conducted to examine farmer knowledge, attitude and practices on sorghum allelopathy... -
Evaluating equity analyst forecasts in South Africa
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Sajjaad Ahmed --- , South Africa Emlyn Flint --- , South AfricaSell-side fundamental analyst reports are highly valued in the financial industry and include three main quantitative components: earnings forecasts, target prices, and buy/sell recommendations. This paper examines analyst accuracy by investigating forecasts made on South African equities over the period... -
Eelgrass Zostera capensis populations in KwaZulu-Natal, South Africa, harbour distinct genomic signals despite limited geographical distance
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SE Smit --- Stellenbosch University, South Africa R Henriques --- University of Pretoria, South Africa M Jackson --- Stellenbosch University, South Africa R Taylor --- , South Africa L Vivier --- University of Zululand, South Africa S von der Heyden --- Stellenbosch University, South AfricaSeagrasses are threatened by anthropogenic stressors and climate change, with numerous population declines reported. In South Africa, the eelgrass Zostera capensis is restricted to estuarine environments and has a disjunct distribution and declining status. With the majority of the distribution... -
Perceived social support and academic persistence among undergraduate students: Mediation of sense of belonging and intrinsic motivation
Item type: Journal Article • Journal: Journal of Psychology in Africa • Authors: Bongani V. Mtshweni --- University of South Africa, South AfricaThis study investigated the mediating effect of sense of belonging and intrinsic motivation on the relationship between perceived social support and academic persistence among undergraduate students. The sample comprised 489 undergraduate students from a South African university (female = 71.2%;...