The influence of citrus orchard age on the ecology of entomopathogenic fungi and nematodes
- Authors: Albertyn ,Sonnica , Moore, Sean D , Marsberg, Tamryn , Coombes, Candice A , Hill, Martin P
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417545 , vital:71462 , xlink:href="https://hdl.handle.net/10520/ejc-cristal-v10-n1-a7"
- Description: A three-year survey of the ecology of entomopathogenic nematodes (EPN) and entomopathogenic fungi (EPF) was undertaken on soils from citrus orchards of different ages to determine the influence of orchard age on the ecology of entomopathogenic fungi and nematodes. The influence of mulch and irrigation method on the occurrence of EPN and EPF was also determined. Most of the isolates recovered (n = 810) were Beauveria sp. (87.88% of all isolates), followed by Metarhizium sp. (11.87% of all isolates). Only 0.24% of soil samples collected during this study tested positive for EPN. All EPN isolates recovered were Heterorhabditis bacteriophora. No significant differences in EPF occurrence were recorded between orchards under drip and micro-sprinkler irrigation. EPF occurrence was significantly lower (P = 0.016) in orchards covered by mulch (31.85% ± 2.07% occurrence) than in orchards with no covering (38.57% ± 1.57% occurrence). EPF occurrence of 40.33 ± 2.13% was highest in non-bearing orchards, followed by mature orchards (nine years or older) (36.76 ± 2.05% of samples) with the lowest EPF occurrence of 25.30 ± 2.02% reported in juvenile orchards (four to eight years old). Juvenile orchards sustain significantly less EPF than mature and non-bearing orchards because of the combined negative impact of less favourable environmental conditions (lower shade density) and fungicide applications.
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The Unintended Consequences of Using Direct Incentives to Drive the Complex Task of Research Dissemination
- Authors: Muthama, Evelyn , McKenna, Sioux
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187116 , vital:44569 , xlink:href="https://doi.org/10.25159/1947-9417/6688"
- Description: Universities have used an array of incentives to increase academic publications, which are highly rewarded in the South African higher education funding formula. While all universities use indirect incentives, such as linking promotion and probation to publication, the mechanisms used in some institutions have taken a very direct form, whereby authors are paid to publish. This process has paralleled a large rise in publication outputs alongside increased concerns about quality. Significantly, there are ethical questions to be asked when knowledge dissemination is so explicitly linked to financial reward through the payment of commission to academics. Based on an analysis of institutional policies and data from an online survey and interviews with academics from seven South African universities, we argue that when money is the main means used to encourage academics to contribute to knowledge, numerous unintended consequences may emerge. These include a focus on quantity rather than the quality of research, a rise in predatory publishing, and resentment among academics. We argue that incentives, in particular direct payment for publications, undermine the academic project by positioning publications in terms of exchange-value rather than their use-value as a contribution to knowledge building.
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