Peanut Web Blotch: I. Cultural Characteristics and Identity of Causal Fungus1

1984 ◽  
Vol 11 (2) ◽  
pp. 109-114 ◽  
Author(s):  
R. A. Taber ◽  
R. E. Pettit ◽  
G. L. Philley
Keyword(s):  
South Africa ◽  
Cultural Studies ◽  
Mycelial Growth ◽  
Fungal Species ◽  
Optimum Temperature ◽  
Cultural Characteristics ◽  
Foliar Disease ◽  
The Usa

Abstract A foliar disease of peanuts, previously unreported in the USA, was found in Texas in 1972. The pathogen was identified as a species of Ascochyta. Further cultural studies have revealed this fungus to be Phoma arachidicola Marasas, Pauer, and Boerema. Pycnidia form profusely at 20 C and 25 C. Pycnidiospores are borne on short pycnidiosphores and are predominantly one-celled in culture. Spores produced in pycnidia on infected leaflets become 1 septate. Large 1-septate spores, as well as an occasional 2-septate spore, may form in culture. Optimum temperature for mycelial growth in 20 C; little or no growth occurs at 5 C or above 30 C. The teleomorphic state develops in the field on fallen leaflets and can be induced to form in the laboratory on sterilized peanut leaflets between 15 and 20 C. Cultures derived from single ascospores form pseudothecia. Pycnidiospores, ascospores, and chlamydospores are all infective units. Because this fungus produces hyaline ascospores and pseudoparaphyses, it has been transferred to the genus Didymella as Didymella arachidicola (Choch.) comb. nov. Comparisons with 15 isolates causing web blotch of peanut in the USA, Argentina, and South Africa indicate that web blotch symptoms are produced by the same fungal species.

scholarly journals Metabolomic Analysis of The Chemical Diversity of South Africa Leaf Litter Fungal Species Using an Epigenetic Culture-Based Approach

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4262
Author(s):  
Rachel Serrano ◽  
Víctor González-Menéndez ◽  
Germán Martínez ◽  
Clara Toro ◽  
Jesús Martín ◽  
...  
Keyword(s):  
South Africa ◽  
Genome Mining ◽  
Fungal Species ◽  
Chemical Diversity ◽  
Fermentation Conditions ◽  
Metabolite Profiles ◽  
Different Populations ◽  
Fungal Genomes ◽  
Microbial Natural Products ◽  
Fermentation Media

Microbial natural products are an invaluable resource for the biotechnological industry. Genome mining studies have highlighted the huge biosynthetic potential of fungi, which is underexploited by standard fermentation conditions. Epigenetic effectors and/or cultivation-based approaches have successfully been applied to activate cryptic biosynthetic pathways in order to produce the chemical diversity suggested in available fungal genomes. The addition of Suberoylanilide Hydroxamic Acid to fermentation processes was evaluated to assess its effect on the metabolomic diversity of a taxonomically diverse fungal population. Here, metabolomic methodologies were implemented to identify changes in secondary metabolite profiles to determine the best fermentation conditions. The results confirmed previously described effects of the epigenetic modifier on the metabolism of a population of 232 wide diverse South Africa fungal strains cultured in different fermentation media where the induction of differential metabolites was observed. Furthermore, one solid-state fermentation (BRFT medium), two classic successful liquid fermentation media (LSFM and YES) and two new liquid media formulations (MCKX and SMK-II) were compared to identify the most productive conditions for the different populations of taxonomic subgroups.

scholarly journals Boundaries of solidarity: a meta-ethnography of mask use during past epidemics to inform SARS-CoV-2 suppression

2021 ◽  
Vol 6 (1) ◽  
pp. e004068
Author(s):  
Po Man Tsang ◽  
Audrey Prost
Keyword(s):  
South Africa ◽  
Risk Perception ◽  
Healthcare Access ◽  
Individual Responsibility ◽  
Trust In Government ◽  
Political Leaders ◽  
Collective Levels ◽  
The Social ◽  
Social Meanings ◽  
The Usa

BackgroundMany countries aiming to suppress SARS-CoV-2 recommend the use of face masks by the general public. The social meanings attached to masks may influence their use, but remain underinvestigated.MethodsWe systematically searched eight databases for studies containing qualitative data on public mask use during past epidemics, and used meta-ethnography to explore their social meanings. We compared key concepts within and across studies, then jointly wrote a critical synthesis.ResultsWe found nine studies from China (n=5), Japan (n=1), Mexico (n=1), South Africa (n=1) and the USA (n=1). All studies describing routine mask use during epidemics were from East Asia. Participants identified masks as symbols of solidarity, civic responsibility and an allegiance to science. This effect was amplified by heightened risk perception (eg, during SARS in 2003), and by seeing masks on political leaders and in outdoor public spaces. Masks also acted as containment devices to manage threats to identity at personal and collective levels. In China and Japan, public and corporate campaigns framed routine mask use as individual responsibility for disease prevention in return for state- or corporate-sponsored healthcare access. In most studies, mask use waned as risk perception fell. In contexts where masks were mostly worn by patients with specific diseases (eg, for patients with tuberculosis in South Africa), or when trust in government was low (eg, during H1N1 in Mexico), participants described masks as stigmatising, uncomfortable or oppressive.ConclusionFace masks can take on positive social meanings linked to solidarity and altruism during epidemics. Unfortunately, these positive meanings can fail to take hold when risk perception falls, rules are seen as complex or unfair, and trust in government is low. At such times, ensuring continued use is likely to require additional efforts to promote locally appropriate positive social meanings, simplifying rules for use and ensuring fair enforcement.

Psychometric Testing as an Unfair Labour Practice

1986 ◽  
Vol 16 (3) ◽  
pp. 79-86 ◽  
Author(s):  
J.M. Taylor ◽  
E.J. Radford
Keyword(s):  
South Africa ◽  
Ethnic Groups ◽  
Test Scores ◽  
Psychometric Testing ◽  
Moderator Variable ◽  
Ability Test ◽  
Labour Relations ◽  
Ability Tests ◽  
Labour Practice ◽  
The Usa

The concept of unfair labour practice has been introduced into South Africa through the Labour Relations Act and it is argued that certain psychometric testing practices can be interpreted as falling under the definition of an unfair labour practice. Empirical results are presented indicating that different ethnic groups obtain significantly different mean ability test scores. A case-study is cited to show that this would result in underprediction of performance on a criterion for the lower scoring of two groups if test scores are regarded as comparable. It is argued that any interpretation of psychometric data in South Africa that does not take account of possible differences between ethnic groups is likely to ignore a significant moderator variable, given the history of ethnically based discriminatory practices in this country. Arguments based on meta-analytical research in the USA, to the effect that psychometric ability tests do not discriminate unfairly against disadvantaged groups if the same tests and norms are used, should not be assumed to hold in South Africa. Various conceptions of what constitutes fairness in selection are considered, and it is concluded that there is a need for employers to make explicit in their selection policies the trade-off between economic and social costs of employment practices. Finally, some implications for users of psychometric tests in industry are considered, in order to forewarn of likely developments in this field.

scholarly journals The use of real life contexts in the CTA: Some unintended consequences

Pythagoras ◽  
2009 ◽  
Vol 0 (69) ◽  
Author(s):  
Sarah Bansilal
Keyword(s):  
South Africa ◽  
Real Life ◽  
Unintended Consequences ◽  
Assessment Programme ◽  
Assessment Tasks ◽  
The Usa ◽  
The Common ◽  
The Uk ◽  
Assessment Activities

The Common Tasks for Assessment (CTA) was a new assessment programme that was introduced in 2002 in South Africa for all Grade 9 learners. The purpose of this paper is to articulate some concerns around the use of contextualised assessment activities in the CTA. The study reported here was carried out in 2003. Data for the study was generated from lesson observations and interviews with the participant teachers and groups of learners. It is argued that although the intentions behind the design of the CTA are well meaning and noble, there are in fact some learners who may be unintentionally disadvantaged by the design of the CTA which uses an extended context as a source for all the assessment tasks. In this paper two unintended consequences of using ‘real life’ contexts are identified and the implications of these are discussed, by linking the observations to research carried out in the UK and the USA.

scholarly journals IAU (Maser) Symposium 287 Summary

2012 ◽  
Vol 8 (S287) ◽  
pp. 506-515 ◽  
Author(s):  
Karl M. Menten
Keyword(s):  
South Africa ◽  
Rio De Janeiro ◽  
State Of The Art ◽  
The State ◽  
Cosmic Masers ◽  
The Usa

Almost exactly twenty years ago, the first of a series of conferences dedicated to cosmic masers took place in Arlington, Virginia in the USA (March 9–11, 1992). Two more followed, each on a different continent, in Mangaratiba, near Rio de Janeiro, Brasil (March 5–10, 2001) and in Alice Springs, Australia (March 12–16, 2007). As at all others, a large part of the international maser community convened from January 29 to February 3, 2012 in splendid Stellenbosch, South Africa, to discuss the state of the art of the field.

An Integrated Assessment of Water Markets: Australia, Chile, China, South Africa and the USA

2010 ◽  
Author(s):  
Gary D. Libecap ◽  
R. Quentin Grafton ◽  
Clay Landry ◽  
Sam McGlennon ◽  
R. J. O'Brien
Keyword(s):  
South Africa ◽  
Integrated Assessment ◽  
Water Markets ◽  
The Usa

scholarly journals The competitive status of the South African Wheat Industry

2016 ◽  
Vol 9 (3) ◽  
pp. 651-666 ◽  
Author(s):  
Johannes Van der Merwe ◽  
Philippus Cloete ◽  
Herman Van Schalkwyk
Keyword(s):  
South Africa ◽  
Competitive Advantage ◽  
South African ◽  
Wheat Flour ◽  
Value Chain ◽  
Institutional Environment ◽  
The South ◽  
Wheat Market ◽  
The Usa ◽  
Trade Partners

This article investigates the competitiveness of the South African wheat industry and compares it to its major trade partners. Since 1997, the wheat-to-bread value chain has been characterised by concentration of ownership and regulation. This led to concerns that the local wheat market is losing international competitiveness. The competitive status of the wheat industry, and its sub-sectors, is determined through the estimation of the relative trade advantage (RTA). The results revealed declining competitiveness of local wheat producers. Compared to the major global wheat producers, such as Argentina, Australia, Brazil, Canada, Germany and the USA, South Africa’s unprocessed wheat industry is uncompetitive. At the same time, South Africa has a competitive advantage in semi-processed wheat, especially wheat flour. The institutional environment enables the importation of raw wheat at lower prices and exports processed wheat flour competitively to the rest of Africa.

scholarly journals Eutypa, Eutypella, and Cryptovalsa Species (Diatrypaceae) Associated with Prunus Species in South Africa

Plant Disease ◽  
2018 ◽  
Vol 102 (7) ◽  
pp. 1402-1409 ◽  
Author(s):  
Providence Moyo ◽  
Ulrike Damm ◽  
Lizel Mostert ◽  
Francois Halleen
Keyword(s):  
South Africa ◽  
Phylogenetic Analyses ◽  
Fruit Trees ◽  
Fungal Species ◽  
Stone Fruit ◽  
Prunus Species ◽  
Internal Transcribed Spacer Region ◽  
Eutypa Lata ◽  
Eutypa Dieback ◽  
Prunus Spp

Stone fruit trees (Prunus spp.) are economically important fruit trees cultivated in South Africa. These trees are often grown in close proximity to vineyards and are to a large extent affected by the same trunk disease pathogens as grapevines. The aim of the present study was to determine whether stone fruit trees are inhabited by Diatrypaceae species known from grapevines and whether these trees could act as alternative hosts for these fungal species. Isolations were carried out from symptomatic wood of Prunus species (almond, apricot, cherry, nectarine, peach, and plum) in stone fruit growing areas in South Africa. Identification of isolates was based on phylogenetic analyses of the internal transcribed spacer region and β-tubulin gene. Forty-six Diatrypaceae isolates were obtained from a total of 380 wood samples, from which five species were identified. All five species have also been associated with dieback of grapevine. The highest number of isolates was found on apricot followed by plum. No Diatrypaceae species were isolated from peach and nectarine. Eutypa lata was the dominant species isolated (26 isolates), followed by Cryptovalsa ampelina (7), Eutypa cremea (5), Eutypella citricola (5), and Eutypella microtheca (3). First reports from Prunus spp. are E. cremea, E. citricola, and E. microtheca. Pathogenicity tests conducted on apricot and plum revealed that all these species are pathogenic to these hosts, causing red-brown necrotic lesions like those typical of Eutypa dieback on apricot.

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