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A comparative photophysicochemical study of phthalocyanines encapsulated in core–shell silica nanoparticles

- Fashina, Adedayo, Amuhaya, Edith K, Nyokong, Tebello

Authors: Fashina, Adedayo , Amuhaya, Edith K , Nyokong, Tebello
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/189708 , vital:44924 , xlink:href="https://doi.org/10.1016/j.saa.2014.08.062"
Description: This work presents the synthesis and characterization of a new zinc phthalocyanine complex tetrasubstituted with 3-carboxyphenoxy in the peripheral position. The photophysical properties of the new complex are compared with those of phthalocyanines tetra substituted with 3-carboxyphenoxy or 4- carboxyphenoxy at non-peripheral positions. Three phthalocyanine complexes were encapsulated within silica matrix to form a core shell and the hybrid nanoparticles particles obtained were spherical and mono dispersed. When encapsulated within the silica shell nanoparticles, phthalocyanines showed improved triplet quantum yields and singlet oxygen quantum yields than surface grafted derivatives. The improvements observed could be attributed to the protection provided for the phthalocyanine complexes by the silica matrix.
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Date Issued: 2015

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A Comparison of Four End-User Devices as Thin Clients for Public Access to the Internet in Poor Communities

- Duff, Kevin, Siebörger, Ingrid, Terzoli, Alfredo

Authors: Duff, Kevin , Siebörger, Ingrid , Terzoli, Alfredo
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/430892 , vital:72725 , https://doi.org/10.1007/978-3-319-16886-9_24
Description: In poor areas, where ICT infrastructure is being deployed with devel-opmental aims, there is a need to provide appropriate, sustainable technologies that meet the needs of the local community. Current trends for ICT interventions favour the use of mobile user equipment, such as tablets and cellphones, but we think that they are inappropriate to allow production as opposed to mainly consumption of digital con-tent, at least for the foreseeable future. Thus our objective is to reduce the cost of deployment of traditional communal Internet Access Points using PCs. In this paper we compare four candidate computers to be used as thin clients in such settings, according to seven different cate-gories. Our study identifies the strengths, weaknesses and problems of each device, and concludes with recommendations for anybody wish-ing to deploy such devices as Linux Terminal Server Project (LTSP) thin clients in a public Internet Access Point.
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Date Issued: 2015

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A comparison of genetic structure in two low-dispersal crabs from the Wild Coast, South Africa

- Qhaji, Y, Jansen van Vuuren, Bettine, Papadopoulos, Isabelle, McQuaid, Christopher D, Teske, Peter R

Authors: Qhaji, Y , Jansen van Vuuren, Bettine , Papadopoulos, Isabelle , McQuaid, Christopher D , Teske, Peter R
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/444770 , vital:74297 , https://doi.org/10.2989/1814232X.2015.1077474
Description: The Wild Coast in south-eastern South Africa is strongly influenced by the warm, southward-flowing Agulhas Current. This current has a significant impact on dispersal in the coastal biota of the region, and facilitates high levels of connectivity among populations. However, it is not known how the region's high-velocity hydrology affects genetic population structure in endemic estuarine species, populations of which are frequently isolated from the sea. Here, we compared genetic structure in two estuarine crabs of the family Hymenosomatidae. Both are presumed to have low dispersal potential, but they differ in terms of their life histories. Hymenosoma longicrure has abbreviated larval development and can complete its entire life cycle within estuaries, whereas Neorhynchoplax bovis is a direct developer that lacks planktonic larvae.
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Date Issued: 2015

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A Connection Management System to Enable the Wireless Transmission of MIDI Messages

- Shaw, Brent, Foss, Richard

Authors: Shaw, Brent , Foss, Richard
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/426829 , vital:72394 , https://www.aes.org/e-lib/browse.cfm?elib=18030
Description: This paper examines the design and implementation of a wireless system for the distribution of MIDI messages for show control and studio environments. The system makes use of the MIDI and MIDINet protocols, creating wireless nodes that will enable the transmission of MIDI between devices on a wireless network with connection management capabilities through the use of embedded web servers. The paper describes the current state of the art, configuration of the system, hardware architectures, software design, and implementation.
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Date Issued: 2015

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A critical assessment of economic policies and their impact on entrepreneurship development in South Africa: a case of Khayelitsha Township in Cape Town

- Oduwole, Olusola https://orcid.org/0000-0002-1563-7392

Authors: Oduwole, Olusola https://orcid.org/0000-0002-1563-7392
Date: 2015
Subjects: Entrepreneurship , Economic policy , Economic development -- South Africa
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10353/26302 , vital:65236
Description: The complexity of the South African society due to past systematic exclusion of some communities from economic activities resulted in the triple challenge of poverty, inequality and unemployment. Although various economic policies had been developed since the advent of the democratic dispensation in 1994, these policies focused on levelling the economic environment, poverty alleviation and massive social security system. However, despite all the interventions, South Africa remains one of the most unequal societies in the world. This is profiled by the mushrooming of informal settlements around cities with job seekers and frequent protests by people who are impatient to experience improvement in their quality of life and who feel cheated out of their social contract. Advocacy from the governing party’s tripartite alliance towards a developmental state had placed more obligations on the government. This requires deliberate interventions through policies implementation to improve or at best alleviate the well-being of the citizenry. A survey conducted in the township of Khayelitsha to assess the impact of such economic policies on the development of entrepreneurship. Khayelitsha is one of South Africa’s largest townships, an informal settlement profiled by unemployment, poor infrastructure and unavailability of basic services. The study explored the entrepreneurial perception, start-up barriers, entrepreneurship climate, and general cultural factors relating to the environment of entrepreneurship development. The results reveal that despite the various economic policies, high level of unwillingness of citizens towards entrepreneurial activity and business venture is rife notwithstanding the high level of unemployment and poverty. The antidote to these challenges would be a rapid entrepreneurship drive among people most affected that would cause them to mind their own business” and become “masters of their own destinies. Given the complexity and massiveness of the challenges, the conclusion shows that a pragmatic solution is required. Therefore, the emancipation of entrepreneurship development in South Africa townships needs attention. The recommended solution is a pragmatic and innovative strategy based on the acronyms NEEDS HELP which stand for Neighbourhood Enhancement and Environmental Development Strategy and Holistic Entrepreneurial Lifestyle Programme. , Thesis (PhD) -- Faculty of Management and Commerce, 2015
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Date Issued: 2015

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A description of gametogenesis in the panga Pterogymnus laniarius (Pisces: Sparidae) with comments on changes in maturity patterns over the past two decades

- Booth, Anthony J, Hecht, Thomas

Authors: Booth, Anthony J , Hecht, Thomas
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/123542 , vital:35452 , https://doi.org/10.1080/02541858.1997.11448428
Description: A description of gametogenesis in the panga Pferogymnus laniarius, a common endemic seabream species inhabiting the Agulhas Bank, South Africa, is presented. After sexual maturity, oogenesis and spermatogenesis continued throughout the year and were found to be similar to these processes in other seabream species and teleosts in general. Analysis of maturity data over the past two decades revealed a significant change in both age and size-at-maturity, a response to fishing pressure.
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Date Issued: 2015

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A narrative-discursive analysis of abortion decision making in Zimbabwe:

- Chiweshe, Malvern T, Macleod, Catriona I

Authors: Chiweshe, Malvern T , Macleod, Catriona I
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/143882 , vital:38291 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
Description: The available research on abortion-decision-making tends to focus on the ‘factors’ or ‘influences’ that are seen to affect abortion decision-making. This approach is rarely able to account for the complex, multi-faceted nature of abortion decision-making, and is often not located within a framework that can unpick the complex array of power relations that underpin the ‘process’ of abortion decision-making. Data reported on in this paper were collected from three sites in Zimbabwe. Narrative interviews were conducted with 18 women who had terminated pregnancies (six at each site) and semi-structured interviews were conducted with six service providers. The women employed discursive resources around stigma, religion, health and culture in telling stories around abortion shame, abortion as justified and the fearful, secretive act of abortion. Comparisons of the way women positioned themselves and how they were positioned by health service providers point to the availability and embeddedness of social discourses and power relations that work to enable/constrain reproductive justice.
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Date Issued: 2015

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A quantitative analysis of microplastic pollution along the south-eastern coastline of South Africa

- Nel, Holly A, Froneman, P William

Authors: Nel, Holly A , Froneman, P William
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/68032 , vital:29187 , https://doi.org/10.1016/j.marpolbul.2015.09.043
Description: Publisher version , The extent of microplastic pollution (< 5 mm) in the southern hemisphere, particularly southern Africa, is largely unknown. This study aimed to evaluate microplastic pollution along the south-eastern coastline of South Africa, looking at whether bays are characterised by higher microplastic densities than open stretches of coastline in both beach sediment and surf-zone water. Microplastic (mean ± standard error) densities in the beach sediment ranged between 688.9 ± 348.2 and 3308 ± 1449 particles·m− 2, while those in the water column varied between 257.9 ± 53.36 and 1215 ± 276.7 particles·m− 3. With few exceptions there were no significant spatial patterns in either the sediment or water column microplastic densities; with little differences in density between bays and the open coast (P > 0.05). These data indicate that the presence of microplastics were not associated with proximity to land-based sources or population density, but rather is governed by water circulation.
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Date Issued: 2015

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A re-examination of the type material of Entomoneis paludosa (W Smith) Reimer and its morphology and distribution in African waters

- Richoux, Nicole B, Taylor, J C, Dalu, Tatenda, Froneman, P William

Authors: Richoux, Nicole B , Taylor, J C , Dalu, Tatenda , Froneman, P William
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/69179 , vital:29440 , https://doi.org/10.5507/fot.2015.002
Description: The current study aims to enhance the understanding of the distribution and morphology of the diatom Entomoneis paludosa W Smith 1853 in African waters. The type material of Entomoneis paludosa (W Smith) Reimer was examined using light and scanning electron microscopy and the morphological characters were compared with new specimens sampled from a temperate river in South Africa. The wider distribution of this taxon on the African continent is discussed, and its relationship to water quality variables.
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Date Issued: 2015

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A review of current DNS TTL practices

- Van Zyl, Ignus, Rudman, Lauren, Irwin, Barry V W

Authors: Van Zyl, Ignus , Rudman, Lauren , Irwin, Barry V W
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/427813 , vital:72464 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622760_A_review_of_current_DNS_TTL_practices/links/5b9a16e292851c4ba8181b7f/A-review-of-current-DNS-TTL-practices.pdf
Description: This paper provides insight into legitimate DNS domain Time to Live (TTL) activity captured over two live caching servers from the period January to June 2014. DNS TTL practices are identified and compared between frequently queried domains, with respect to the caching servers. A breakdown of TTL practices by Resource Record type is also given, as well as an analysis on the TTL choices of the most frequent Top Level Domains. An analysis of anomalous TTL values with respect to the gathered data is also presented.
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Date Issued: 2015

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A review of three generations of critical theory: Towards conceptualising critical HESD research

- Lotz-Sisitka, Heila

Authors: Lotz-Sisitka, Heila
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/437136 , vital:73345 , ISBN 9781315852249 , https://www.taylorfrancis.com/chapters/edit/10.4324/9781315852249-17/review-three-generations-critical-theory-heila-lotz-sisitka
Description: To begin a review of the purpose(s) of ESD research, we must first ask the basic question of the purpose of research generally. Definitions of research normally centre on it comprising sys-tematic investigation which contributes to knowledge or under-standing of phenomena or a problem. A distinction is common-ly drawn between pure or basic research which focuses on understanding phenomena and issues, and applied research where the primary emphasis is on research which contributes to the solution of problems or some systemic improvement ra-ther than knowledge for its own sake. Some commentators see action research as a third category as it is predicated on the researcher being part of the research process which itself is committed to personal or social change. ESD research as an area of interest is perhaps unusual because it accommodates and crosses these categories. It also engages in philosophic research regarding cultural, worldview and ethical dimensions of sustainability education – critically important dimensions of ESD research, but not within the scope of this chapter. Re-search on – say – the relative effect of different pedagogies, or how a learning environ-ment affects learning, may be thought of as basic research, but at another level, ESD research is often purposeful beyond the accumulation of understanding about educational processes.
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Date Issued: 2015

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A sandbox-based approach to the deobfuscation and dissection of php-based malware

- Wrench, Peter M, Irwin, Barry V W

Authors: Wrench, Peter M , Irwin, Barry V W
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/429258 , vital:72571 , 10.23919/SAIEE.2015.8531886
Description: The creation and proliferation of PHP-based Remote Access Trojans (or web shells) used in both the compromise and post exploitation of web platforms has fuelled research into automated methods of dissecting and analysing these shells. Current malware tools disguise themselves by making use of obfuscation techniques designed to frustrate any efforts to dissect or reverse engineer the code. Advanced code engineering can even cause malware to behave differently if it detects that it is not running on the system for which it was originally targeted. To combat these defensive techniques, this paper presents a sandbox-based environment that aims to accurately mimic a vulnerable host and is capable of semi-automatic semantic dissection and syntactic deobfuscation of PHP code.
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Date Issued: 2015

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Absenting absence: Expanding zones of proximal development in environmental learning processes

- Lotz-Sisitka, Heila

Authors: Lotz-Sisitka, Heila
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/436939 , vital:73318 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
Description: In this chapter I demonstrate that indigenous knowledge practice is com mensurate with critical realist scientific practice. Critical realism under labours for Western scien-tific knowledge, helping to bring its practice in line with its theory. In this paper I similarly underlabour for indigenous knowledge. I use examples from the Eastern Coast of Tan-zania to suggest that the kind of knowledge that is gener-ated through indigenous pro cesses is based on retroduc-tive and retrodictive reasoning (as well as induc tive and deductive reasoning) and is thus grounded in the theory development principles of DREI(C)/RRREI(C) which, ac-cording to Bhaskar (1993), is the basis for all scientific knowledge. The chapter therefore creates a basis for indi-viduals, groups, organiza tions, and institutions that are involved in the field of environment and sustainability edu-cation and have an indigenous knowledge component, to use the DREI(C)/RRREI(C) for learning and research pur-poses. In this way, they can assume the commensurablity of both Western scientific knowledge and indigenous knowledge. This work substantiates the signifi cance of indigenous knowledge as science in its own right, which pursues specified scientific principles and procedures to inform practice or praxis in the coastal learning environ-ment in a manner that may enhance social learning. There already exists a body of literature that regards indigenous knowledge as ‘local science’ (Sillitoe, 2007). However, I hope to expand this view by more closely aligning this ‘lo-cal science’ with the same prac tices used by science in general, where this science is defined according to critical realist principles.
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Date Issued: 2015

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Absenting the absence of parallel learning pathways for intermediate skills: The ‘missing middle' in the environmental sector in South Africa

- Ramsarup, Presha

Authors: Ramsarup, Presha
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/436964 , vital:73320 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
Description: Environment and sustainable development are recognized for: their significance for the future of South Africa’s well-being; their complex, transversal nature; and their associated ‘new-ness’ within South African education and training systems. In a sector with relatively new occupations without clear learning pathways into jobs and where occupational contexts are rapid-ly changing with evolving skill needs, the chapter explores a critical realist dialectical view of learning pathways across sys-tems of work and learning. It highlights the need to develop more sophisticated understandings of learning pathways, and the way in which work, education and training systems inter-face to support the transitions needed for particular forms of work and learning. The chapter also explores how critical real-ist dialectics can help to explain more fully the absence of in-termediate pathways in the environment and sustainable de-velopment ‘sector’ in South Africa. It highlights the absences within the post-school provisioning system and through this analysis raises the patterns of emergence that characterize environmental learning pathways. This then advances an edu-cational critique that assists in the development of deeper knowledge of the object of the study (elements constituting learning pathways) in order to understand possibilities for change and to present opportunities for creating more seam-less environmental learning pathways into green jobs, enhanc-ing social justice potential and public good concerns.
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Date Issued: 2015

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Accommodation and job assignment for impaired workers:

- Pearson, Jessie

Authors: Pearson, Jessie
Date: 2015
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/143661 , vital:38271 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
Description: Some compensation systems do not encourage permanently restricted workers disabled due to work-related injuries, to return to work. However, appropriate job placement of impaired workers has been shown to result in feelings of independence, usefulness and responsibility, as well as financial security. Physically impaired employees in many workplaces have experienced job discrimination because colleagues and supervisors assume that their work performance will be affected by physical limitations resulting from their disability. This theoretical paper discusses the possibilities of assigning workers to appropriate jobs based on their specific capabilities and limitations. The option of providing certain job accommodations in the form of workplace restructuring is also discussed.
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Date Issued: 2015

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Addressing local level food insecurity amongst small-holder communities in transition

- Shackleton, Charlie M, Hamer, Nicholas G, Swallow, Brent M, Ncube, K

Authors: Shackleton, Charlie M , Hamer, Nicholas G , Swallow, Brent M , Ncube, K
Date: 2015
Subjects: Food security -- South Africa Economic development -- South Africa Rural development -- South Africa
Language: English
Type: text
Identifier: http://hdl.handle.net/10962/50090 , vital:25958
Description: Food insecurity affects as significant proportion of the world's population and hence it typically receives priority attention in global policies associated with poverty, equity and sustainable development. For example, it is the first of the Millennium Development Goals and the second of their successor, the Sustainable Development Goals. Access to sufficient and nutritious food is deemed a basic human right. The latest FAO analysis of the “State of Food Insecurity in the World 2014” reports that 805 million people (approximately 11-12% of the world's population) are chronically undernourished (i.e. do not have sufficient energy intake over a period of at least one year). In sub-Saharan Africa the prevalence remains stubbornly high at 24%, the highest in the world. Whilst most interpret food insecurity to mean an insufficient quantity of food (as measured by the number of calories consumed), the widely accepted FAO definition considers four dimensions of food security, namely quantity, quality or diversity, access and use. Provision of enough calories on a daily basis is not sufficient if the diet lacks diversity and appropriate balance to provide the full range of minerals and vitamins necessary for proper health, or if the food available is culturally unacceptable. Thus, there is a pressing need for more nuanced analyses of food security against all four of the dimensions embedded in the concept. Additionally, it is important that these be measured at more local or regional levels because national statistics can mask alarming regional discrepancies in food security, or amongst particular sectors of society, such as recent migrants, refugees, female- or child-headed households, those vulnerable to HIV/AIDS or the landless, to mention just a few. For example, at a national level South Africa is considered a food secure nation with respect to staple requirements, and access to sufficient food is enshrined in the Constitution (Section 27, subsection 1b), but nationally one in twenty (i.e. approx. 2.5 million people) go to bed hungry most nights, and 23% of children below the age of 15 are physically stunted, severely stunted or wasted, due to the long-term ill effects of insufficient food or of inadequate diversity and quality. At a subnational level, there are marked differences between rural and urban populations and even between geographic areas (for example, the prevalence of stunting amongst boys less than 15 years old is 23% in the Eastern Cape, compared to 12% in Gauteng). Once again, despite being a food secure nation, nationally 40% of the population have a dietary diversity score of four or less, which is a cut-off point signifying poor dietary diversity which makes people more vulnerable to malnutrition and ill health, and in Limpopo and Northwest provinces it is as high as 66% and 61%, respectively.
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Date Issued: 2015

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Africa in global International relations: emerging approaches to theory and practice: an introduction

- Bischoff, Paul, 1954-, Aning, Kwesi, Acharya, Amitav

Authors: Bischoff, Paul, 1954- , Aning, Kwesi , Acharya, Amitav
Date: 2015
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/161662 , vital:40651 , ISBN 9781317437536
Description: This book investigates why Africa has been marginalised in IR discipline and theory and how this issue can be addressed in the context of the emerging Global IR paradigm. To have relevance for Africa, a new IR theory needs to be more inclusive, intellectually negotiated and holistically steeped in the African context. In this innovative volume, each author takes a critical look at existing IR paradigms and offers a unique perspective based on the African experience. Following on from Amitav Acharya and Barry Buzan’s work, Non-Western International Relations Theory, it develops and advances non-Western IR theory and the idea of Global IR.
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Date Issued: 2015

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Agathis bishopi (Hymenoptera: Braconidae) as a potential tool for detecting oranges infested with Thaumatotibia leucotreta (Lepidoptera: Tortricidae)

- Zimba, Kennedy J, Hill, Martin P, Moore, Sean D, Heshula, Unathi

Authors: Zimba, Kennedy J , Hill, Martin P , Moore, Sean D , Heshula, Unathi
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/423955 , vital:72108 , xlink:href="https://doi.org/10.1007/s10905-015-9526-0"
Description: In South Africa, Thaumatotibia leucotreta is a key pest of citrus impacting its production and trade. Detection of newly infested fruit by visual inspection is challenging and poses a risk of packing infested with healthy fruit for export. Agathis bishopi is a larval endoparasitoid of T. leucotreta, attacking early larval instars. Understanding how A. bishopi parasitoids locate fruit infested with their host is of interest for developing an efficient detector for T. leucotreta infested fruit. The response of female adult A. bishopi parasitoids to olfactory and visual cues associated with T. leucotreta infested fruit were evaluated using a Y-tube olfactometer and flight tunnel. Agathis bishopi parasitoids were strongly attracted to infested fruit over healthy fruit, either when only olfactory or combinations of visual and olfactory cues were offered. Among the four synthetic compounds tested, D-limonene and ocimene elicited a strong attraction to parasitoids with response rates of 92 % and 72 % respectively. A blend of four synthetic compounds simulating T. leucotreta infested fruit odour equally elicited strong attraction to parasitoids (84 % response rate). Attraction of parasitoids to infested fruit cues was heightened by prior experience, suggesting the occurrence of associative learning. Results from this study indicate that A. bishopi parasitoids mainly rely on olfactory cues in host habitat location and that D-limonene and ocimene are the major attractants in infested fruit volatiles. These findings and the potential for manipulating A. bishopi for detection of infested fruit in the packhouse are discussed.
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Date Issued: 2015

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Agathis bishopi, a larval parasitoid of false codling moth Thaumatotibia leucotreta: laboratory rearing and effect of adult food on parasitism and longevity

- Zimba, Kennedy J, Moore, Sean D, Heshula, Lelethu U P, Hill, Martin P

Authors: Zimba, Kennedy J , Moore, Sean D , Heshula, Lelethu U P , Hill, Martin P
Date: 2015
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/406985 , vital:70328 , xlink:href="https://hdl.handle.net/10520/EJC185849"
Description: Agathis bishopi (Nixon) (Hymenoptera: Braconidae) is a koinobiont larval endoparasitoid of false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), a pest of economic importance on citrus in South Africa. In the field Agathis bishopi was found to parasitise up to 34 % of FCM larvae in fruit, reflecting reasonable biocontrol potential. Improving the rearing of A. bishopi would therefore complement the existing biocontrol strategies for FCM. In several parasitic wasps, sugar concentration and feeding duration has been shown to influence parasitism and longevity. However, their effect on parasitism and longevity of A. bishopi is unknown. In the present study a rearing protocol for A. bishopi is described, including evaluation of the effects of honey concentration on parasitoid longevity. On average, 18.2%of FCM larvae in rearing containers were parasitised under the rearing protocol described. Cotton wool, instead of paper towelling, as honey carrier for feeding parasitoids in rearing containers significantly increased parasitism and yield of offspring. Furthermore, longevity significantly increased with higher concentrations of honey. Maximum lifespan duration for male and female parasitoids was achieved when parasitoids were fed on 36 % (w/v) honey. Results from this study indicate that A. bishopi requires a sufficient concentration of sugar, coupled with frequent and prolonged feeding on a cotton wool substrate, in order to achieve maximum parasitism and longevity. Such information provides a basis for optimising mass-rearing and longevity of A. bishopi and parasitism of FCM in orchards.
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Date Issued: 2015

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