Articles de revues : « Agricultural pests – South Africa »

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Gambiza. « Permaculture : Challenges and benefits in improving rural livelihoods in South Africa and Zimbabwe ». Sustainability 11, n^o 8 (12 avril 2019) : 2219. http://dx.doi.org/10.3390/su11082219.

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Feeding a growing global population using conventional agricultural practices is leading toadverse environmental impacts. There is a call for alternative forms of agriculture that address social,economic, and environmental aspects of sustainability. Permaculture is a holistic design frameworkthat incorporates sustainable agricultural practices, potentially improving livelihoods. This studylooked at the challenges and benefits of permaculture in improving rural livelihoods in Zimbabweand South Africa. We used semi-structured interviews to collect data. Permaculture contributed over40% to total income for participants in both countries. However, permaculture was not the dominantsource of income and periodically straddled multiple livelihood strategies. The main benefits ofpermaculture were identified as improved human health, increased resilience to environmentalchanges, and reduction of input costs. The key challenges included high labour input, infestationof pests and diseases, and lack of knowledge on permaculture practices. Although permaculturepresents significant challenges, its integration with other forms of sustainable agricultural practicescan contribute to improved rural livelihoods.

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Timm, A. E., H. Geertsema et L. Warnich. « Population genetic structure of economically important Tortricidae (Lepidoptera) in South Africa : a comparative analysis ». Bulletin of Entomological Research 100, n^o 4 (27 novembre 2009) : 421–31. http://dx.doi.org/10.1017/s0007485309990435.

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AbstractComparative studies of the population genetic structures of agricultural pests can elucidate the factors by which their population levels are affected, which is useful for designing pest management programs. This approach was used to provide insight into the six Tortricidae of major economic importance in South Africa. The population genetic structure of the carnation wormE. acerbellaand the false codling mothT. leucotreta, analyzed using amplified fragment length polymorphism (AFLP) analysis, is presented here for the first time. These results were compared with those obtained previously for the codling mothCydia pomonella, the oriental fruit mothGrapholita molesta, the litchi mothCryptophlebia peltasticaand the macadamia nut borerT. batrachopa. Locally adapted populations were detected over local geographic areas for all species. No significant differences were found among population genetic structures as result of population history (whether native or introduced) although host range (whether oligophagous or polyphagous) had a small but significant effect. It is concluded that factors such as dispersal ability and agricultural practices have the most important effects on genetically structuring populations of the economically important Tortricidae in South Africa.

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Swartz, Alison, Susan Levine, Hanna-Andrea Rother et Fritha Langerman. « Toxic layering through three disciplinary lenses : childhood poisoning and street pesticide use in Cape Town, South Africa ». Medical Humanities 44, n^o 4 (20 octobre 2018) : 247–52. http://dx.doi.org/10.1136/medhum-2018-011488.

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This article focuses on the devastating hidden perils of agricultural pesticides repurposed by informal sellers in urban South African townships to kill rats and other unwanted pests. Drawing on collaborative research techniques, we investigate the causal relationship between child poisoning episodes and the household use of illegal street pesticides. Such pesticides are used to safeguard homes from pests in an attempt to protect children from the harmful consequences of rodent bites and vectorborne diseases. Here, we consider the social injustice and economic inequality of episodes of child pesticide poisoning in the Western Cape from three disciplinary perspectives: public health, medical anthropology and fine art. We ultimately seek to demonstrate the complex relationship between the political economy of sanitation, waste removal and insecure housing, and the proliferation of rodents and other pests in urban townships. As a contribution to the medical humanities, the paper leans into different disciplines to highlight the toxic layering at play in a child pesticide poisoning event. The public health perspective focuses on the circulation of illegal street pesticides, the anthropologists focus on the experiences of the children and caregivers who are victims of poisoning, and the fine artist centres the rat within a broader environmental context. While non-toxic methods to eliminate rats and household pests are critical, longer term structural changes, through environmental and human rights activism, are necessary to ameliorate the suffering caused by poisoning. The medical and health humanities is well poised to highlight creative ways to draw public attention to these challenges, as well as to bridge the divide between science and the humanities through collaborative research efforts. With this paper we set the stage for discussing and balancing perspectives when addressing pest control in poor urban communities.

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Peebles, Jamie, Ephraim Gwebu, Opeoluwa Oyedeji, Sarah Nanyonga, Nokuthula Kunene, David Jackson, William Setzer et Adebola Oyedeji. « Composition and Biological Potential of Essential Oil from Thelechitonia trilobata Growing in South Africa ». Natural Product Communications 6, n^o 12 (décembre 2011) : 1934578X1100601. http://dx.doi.org/10.1177/1934578x1100601238.

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Thelechitonia trilobata is regarded as a troublesome weed that grows to form a dense blanket over the soil preventing the growth of other crops in farmland. Although the plant is regarded as a notorious, invasive plant, its chemical composition and biological potential have not been reported. The essential oil was isolated from the fresh leaves of T. trilobata using hydrodistillation. α-Pinene (21.6%), α-phellendrene (21.0%), limonene (12.8%) and germacrene D (7.5%) were the major constituents of the oil. The essential oil was screened against agricultural pests. The anti-tick properties were tested on Ripicephalus e. ervertsi found on sheep, while repellency, fumigation, and contact toxicity tests were carried out with maize weevils. Except for the contact toxicity test, all other bioassays gave positive results.

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LIAO, JHIH-RONG, CHYI-CHEN HO et CHIUN-CHENG KO. « Predatory mites (Acari : Mesostigmata : Phytoseiidae) intercepted from samples imported to Taiwan, with description of a new species ». Zootaxa 4927, n^o 3 (15 février 2021) : 301–30. http://dx.doi.org/10.11646/zootaxa.4927.3.1.

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Global trade has increased the invasion risk of exotic organisms and damaged agricultural and natural ecosystems. The Bureau of Animal and Plant Health Inspection and Quarantine (BAPHIQ) handles quarantine services of animal- and plant-associated pests and diseases in Taiwan. The predatory mite family Phytoseiidae (Acari: Mesostigmata) is a well-known group due to the potential use of certain species as biocontrol agents for small phytophagous pests. Some species are available in commercial markets and frequently used in biological control in many agricultural systems, especially in greenhouse crops. However, exotic biological control agents may interfere with natural or naturalised populations of predatory mites and they may threaten indigenous populations via intraguild predation. The present study aims to provide a checklist of phytoseiid mite species found in plant quarantine from 2006–2013. Twenty-five species belonging to two subfamilies and eight genera were found in samples imported to Taiwan from twelve countries, including one new species Typhlodromus (Anthoseius) ueckermanni sp. nov. from South Africa. The checklist provides distribution, remarks, and also an identification key for all species.

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Sourabie, Soumaïla, Patrice Zerbo, Djibril Yonli et Joseph I. Boussim. « Connaissances traditionnelles des plantes locales utilisées contre les bio-agresseurs des cultures et produits agricoles chez le peuple Turka au Burkina Faso ». International Journal of Biological and Chemical Sciences 14, n^o 4 (17 août 2020) : 1390–404. http://dx.doi.org/10.4314/ijbcs.v14i4.18.

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La présente étude a pour objectif de faire l’état des connaissances traditionnelles endogènes relatives aux plantes locales utilisées contre les bio-agresseurs des cultures et des produits agricoles. A travers une série d’enquêtes ethnobotaniques réalisée de 2018 à 2019 dans la région des Cascades au Burkina Faso, 150 personnes appartenant à l’ethnie Turka ont été interviewées. Les informations recherchées en utilisant des entretiens semi-directifs, ont concerné les noms locaux des plantes, les parties utilisées, les domaines d’utilisation et leurs modes d'utilisation. Les données collectées ont permis de recenser 33 espèces de plantes réparties en 30 genres et 19 familles utilisées traditionnellement contre les bio-agresseurs agricoles. Ces plantes interviennent sélectivement dans trois domaines : la répulsion des insectes, l’inhibition des herbes envahissantes et la construction des greniers. Les espèces sont utilisées soit directement ou transformées en poudre ou en cendre. Les feuilles sont plus utilisées que les autres organes. Cassia nigricans est l’espèce la plus utilisée pour son effet répulsif et Parkia biglobosa pour son effet inhibiteur. Des études approfondies sur les propriétés chimiques des potentielles espèces permettront de réduire l’impact des produits chimiques en agriculture contre les bio-agresseurs.Mots clés : Ethnobotanique, diversité végétale, ennemi agricole, secteur sud-soudanien, Afrique de l’ouest English Title:Traditional knowledge of local plants used against pests of crops and agricultural products among the Turka poeple in Burkina Faso The objective of this study is to provide an overview of endogenous traditional knowledge relating to local plants used against pests of crops and agricultural products. Through an ethnobotanical’s surveys carried out from 2018 to 2019 in the Cascades area in Burkina, 150 Turka ethnic group people were interviewed. Through semi-structured interviews, information looking for were concerned plants local names, their parts used, the domains and the modes of use. Data collected allowed to identify 33 plants’ species belonged to 30 genera and 19 families, used traditionally against agricultural pests. These plants are selectively involved in three domains: repelling insects, inhibiting invasive weeds and building lofts. Species are used either directly or processed into powder or ash. The leaves are used more than other organs. Cassia nigricans is the most used species for its repellent effect and Parkia biglobosa for its inhibitory effect. In-depth studies on the chemical properties of potential species will reduce the impact of chemicals in agricultural against pests.Keywords: Ethnobotany, plant diversity, agricultural pest, South Sudanese sector, West Africa

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Mkenda, Prisila A., Patrick A. Ndakidemi, Ernest Mbega, Philip C. Stevenson, Sarah E. J. Arnold, Geoff M. Gurr et Steven R. Belmain. « Multiple ecosystem services from field margin vegetation for ecological sustainability in agriculture : scientific evidence and knowledge gaps ». PeerJ 7 (28 novembre 2019) : e8091. http://dx.doi.org/10.7717/peerj.8091.

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Background Field margin and non-crop vegetation in agricultural systems are potential ecosystem services providers because they offer semi-natural habitats for both below and above ground animal groups such as soil organisms, small mammals, birds and arthropods that are service supplying units. They are considered as a target area for enhancing farm biodiversity. Methodology To explore the multiple potential benefits of these semi-natural habitats and to identify research trends and knowledge gaps globally, a review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 235 publications from the year 2000 to 2016 in the Scopus and Web of Science databases were reviewed. Results The literature showed an increasing trend in the number of published articles over time with European studies leading in the proportion of studies conducted, followed by North America, Asia, South America, Africa and Australia. Several functional groups of organisms were studied from field margin and non-crop vegetation around agricultural lands including natural enemies (37%), insect pests (22%), birds (17%), pollinators (16%), soil macro fauna (4%) and small mammals (4%). Ecosystem services derived from the field margin included natural pest regulation, pollination, nutrient cycling and reduced offsite erosion. Some field margin plants were reported to host detrimental crop pests, a major ecosystem dis-service, potentially leading to increased pest infestation in the field. Conclusion The majority of studies revealed the importance of field margin and non-crop vegetation around arable fields in enhancing ecosystem biodiversity. Promotion of field margin plants that selectively enhance the population of beneficial organisms would support sustainable food security rather than simply boosting plant diversity. Our analyses also highlight that agro-ecological studies remain largely overlooked in some regions.

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Yusuf, Shehu Folaranmi Gbolahan, Oluwabunmi Oluwaseun Popoola, Lindokhule Gwala et Thinandavha Nesengani. « Promoting University–Community Alliances in the Experiential Learning Activities of Agricultural Extension Postgraduate Students at the University of Fort Hare, South Africa ». Sustainability 13, n^o 18 (18 septembre 2021) : 10411. http://dx.doi.org/10.3390/su131810411.

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This study examines the university–community alliance with regard to experiential learning activities that may be used to enhance the competencies of agricultural extension postgraduate students (AEPS). Through research and alliance, university education provides agricultural extension students with ideal learning spaces to explore cause-related social, economic, and sustainability aspects of agriculture. The objectives of the study were for the AEPS to work on community farms for between six to eight weeks, to identify production challenges, and to attempt to solve problems using a participatory action research (PAR) approach. Students collected data daily, using parameters that included types of agro-enterprise, agricultural practices, observation and control of pests and diseases, identification, and control of weed infestation types, control of predators, and management of various security challenges. Social media were also used to share posts (pictures and videos) of the various project activities with the public for discussion and knowledge sharing. Findings show that there was an improved relationship between the students and their community collaborators. All participants mutually benefited from the programme; students gained indigenous farming knowledge from the farmers, while farmers benefited from the scientific approaches to solving common farming problems employed by the students—mostly improvised technologies with local content. Both the students and the farmers learned from the knowledge shared by various followers on Facebook, who gave suggestions to address some of the challenges posted on social media. The programme advocates the need to shift from a mostly rigid, conventional curriculum to a more dynamic, interactive one, which embraces active experimentation with theoretical knowledge. It underscores the significance of experiential learning for developing students’ technical competencies. The success of the programme could influence curriculum development and re-design to accommodate more experience-based modules.

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Wightman, John A. « Can lessons learned 30 years ago contribute to reducing the impact of the fall army worm Spodoptera frugiperda in Africa and India ? » Outlook on Agriculture 47, n^o 4 (décembre 2018) : 259–69. http://dx.doi.org/10.1177/0030727018814849.

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The rapid spread of the fall army worm ( Spodoptera frugiperda) across sub-Saharan Africa, and now South Asia, has created surprise and distress to the smallholder farmers of both regions who face hunger and economic stress because of this pest. There has been high-quality support from the international agricultural information sector, but there has also been advice that may not be applicable to the farming systems of smallholder farmers. That comment arises from lessons learned from involvement with a similar pest outbreak of a related pest species in India starting in the mid-80s. Post-rainy season groundnut (peanut) Arachis hypogaea is a high-value crop in the coastal region of Andhra Pradesh. Changes in the management of tobacco crops to the North of the groundnut belt resulted in invasions of Spodoptera litura. The groundnut farmers responded by applying a wide range of insecticides that did nothing to protect their crops from further defoliation. Scientists from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) initiated research that enriched the knowledge of this crop–pest relationship. For instance, they showed that groundnut plants could withstand close to complete defoliation with little loss in yield. Farmers also learned that the cessation of their insecticide regime allowed natural enemies of the caterpillars to take over the management of the pests. They were showed how to enhance the populations of the coccinellids and the birds that were the key predators. ‘Citizen Scientists’ led this process. Non- and quasi-governmental organizations took over the extension process. They were provided with ongoing personal and technical support, for instance, the provision of definitive facts about the high levels of insecticide resistance, encouraging cultural control techniques, and of exploiting natural enemies, including entomopathogens. The involvement of the ICRISAT team later extended into the groundnut fields of South East Asia.

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Albert, Reece, et Jurie Moolman. « Protecting Ecosystems by way of Biological Control : Cursory Reflections on the Main Regulatory Instruments for Biological Control Agents, Present and Future ». Potchefstroom Electronic Law Journal/Potchefstroomse Elektroniese Regsblad 16, n^o 2 (3 mai 2017) : 184. http://dx.doi.org/10.17159/1727-3781/2013/v16i2a2347.

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Although there are numerous threats to ecosystems and the resultant ecosystem services, alien and invasive plants (AIP) have been identified as being one of the major causes of ecosystem destruction. In addressing the threat of alien and invasive plants through the use of various mechanisms, the regulatory framework imposed by legislation is key in ensuring that that controlling AIPs does in fact not do more harm than good. One such control mechanism, which has the potential to do wonders or wreak havoc if not adroitly implemented, is that of using biological control agents. This contribution provides a brief overview on the three main regulatory instruments used to control biological control agents in South Africa, namely the Conservation of Agricultural Resources Act 43 of 1983, the Agricultural Pests Act 36 of 1983 and the National Environmental Management: Biodiversity Act 10 of 2004. It also considers possible future developments on the regulation of biological control agents.

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Rivers-Moore, N. A., R. W. Palmer et H. F. Dallas. « Assessing the relative culpability of Simulium (Diptera : Simuliidae) species in recent black fly outbreaks along the middle Orange River, South Africa ». Canadian Journal of Zoology 92, n^o 6 (juin 2014) : 505–13. http://dx.doi.org/10.1139/cjz-2014-0008.

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Black fly along the Orange River are major pests of livestock and labour-intensive agriculture, causing annual estimated industry losses in excess of US$30 million. The problem is attributed to winter high flows, with the main pest species being Simulium chutteri Lewis, 1965, although Simulium damnosum Theobald, 1903 and Simulium impukane de Meillon, 1936 may also be periodically problematic. During 2011, black fly outbreaks along the middle Orange River were perceived by farmers to have worsened and attributed to S. impukane. Here, we investigate the likelihood of this being the case, using a weight-of-evidence approach incorporating ecohydrological data. Results showed that it is unlikely that the 2011 outbreaks were caused by S. impukane, and more likely that the main outbreak cause remains S. chutteri. Sustained high flows and turbidity levels favour S. chutteri species over the other species of black fly, while flow conditions for a species such as S. impukane were favourable for 1% of the time only. However, during periods of lower flow and lower turbidity, other species of black fly may be favoured and contribute towards periodic outbreaks. We conclude that black fly control should focus on management issues around the control programme.

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Venter, Gert J., Karien Labuschagne, I. Hermanides, D. Majatladi, S. Boikanyo et I. Wright. « Foyers récents de peste équine africaine en Afrique du Sud ». Revue d’élevage et de médecine vétérinaire des pays tropicaux 62, n^o 2-4 (1 février 2009) : 104. http://dx.doi.org/10.19182/remvt.10020.

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Based on diagnostic samples received at the Agricultural Research Council – Onderstepoort Veterinary Institute (ARC-OVI), a reference centre for African horse sickness (AHS) and bluetongue (BT) for the World Organisation for Animal Health (OIE), the traditional picture on the presence and occurrence of AHS seems to have changed dramatically in South Africa. Outbreaks of AHS virus (AHSV) have increased in this country over the last three to eight years. Outbreaks tend to occur earlier in the season than normally expected. Unpredicted outbreaks of AHS during the past five years in the declared AHS-free area in the South-Western Cape has led to the temporary closure of the quarantine station in Cape Town and the ban on horse exports from South Africa with significant losses to the horse industry as a whole. In January and February 2006, outbreaks of AHSV serotype 9 have also occurred in the George/Knysna area in the Western Cape. Outbreaks in this area occurred over a relatively long period and continued into the colder months of the year. This seems to indicate that AHSV has overwintered in this frost-free area, and that it could have occurred in cycling hosts (donkeys and zebras) and/or in adult Culicoides species. Since 2001, AHS has occurred annually in the Eastern Cape, South Africa, with at least four serotypes in circulation today. In an outbreak in April 2008 in Port Elisabeth, Eastern Cape, C. bolitinos was the dominant species in the coastal areas, whereas C. imicola was the dominant one in the inland area. In the outbreak in February and March 2008 in Robertson and in Kimberley, Northern Cape, C. imicola was the dominant species. Pools of midges have been tested for virus detection during each outbreak. From the outbreak in Robertson, 13 pools were positive for equine encephalosis virus (EEV) and two for BTV. From the outbreak in Kimberley, EEV was isolated from one pool of C. tuttifrutti. The role of C. tuttifrutti as a vector is still poorly understood.

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Powell, Chante, Virgilio Caleca, Martina Sinno, Michaela van Staden, Simon van Noort, Clint Rhode, Elleunorah Allsopp et Barbara van Asch. « Barcoding of parasitoid wasps (Braconidae and Chalcidoidea) associated with wild and cultivated olives in the Western Cape of South Africa ». Genome 62, n^o 3 (mars 2019) : 183–99. http://dx.doi.org/10.1139/gen-2018-0068.

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Wild and cultivated olives harbor and share a diversity of insects, some of which are considered agricultural pests, such as the olive fruit fly. The assemblage of olive-associated parasitoids and seed wasps is rich and specialized in sub-Saharan Africa, with native species possibly coevolving with their hosts. Although historical entomological surveys reported on the diversity of olive wasp species in the Western Cape Province of South Africa, no comprehensive study has been performed in the region in the molecular era. In this study, a dual approach combining morphological and DNA-based methods was used for the identification of adult specimens reared from olive fruits. Four species of Braconidae and six species of Chalcidoidea were identified, and DNA barcoding methodologies were used to investigate conspecificity among individuals, based on randomly selected representative specimens. Morphological identifications were congruent with DNA data, as NJ and ML trees correctly placed the sequences for each species either at the genus or species level, depending on the available taxa coverage, and genetic distances strongly supported conspecificity. No clear evidence of cryptic diversity was found. Overall seed infestation and parasitism rates were higher in wild olives compared to cultivated olives, and highest for Eupelmus spermophilus and Utetes africanus. These results can be used for early DNA-based detection of wasp larvae in olives and to further investigate the biology and ecology of these species.

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Mansour, Sameeh A. « Persistent organic pollutants (POPs) in Africa : Egyptian scenario ». Human & ; Experimental Toxicology 28, n^o 9 (septembre 2009) : 531–66. http://dx.doi.org/10.1177/0960327109347048.

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Persistent organic pollutants (POPs) are organic (carbon-based) compounds that include synthesized substances (pesticides and polychlorinated biphenyls [PCBs]) and other by-product substances generated as a result of human and natural activity (dioxins and furans). Extensive scientific studies have shown that POPs are some of the most dangerous pollutants released into the environment by humans. Great efforts have been made since the early 1960s to enhance chemical management and safety issues. Various conventions have been adopted for this purpose: the Stockholm Convention (SC) is one of the well-known meetings in this context. The SC on POPs (May 2001) focuses on reducing and eliminating releases of 12 POPs coined the ‘Dirty Dozen’ by the United Nations Environment Program (UNEP). Persistence of such chemicals in soils, air, and water, together with natural processes such as evaporation to the atmosphere and washout by rain and flood, give rise to their ubiquitous distribution in the environment and eventual penetration into food chains and bio-accumulation in humans. Public concern about contamination by POPs increased recently because several of these compounds are identified as hormone disruptors, which can alter normal function of endocrine and reproductive systems in humans and wildlife. African countries are using pesticides, such as dichlorodiphenyltrichloroethane (DDT), lindane, toxaphene, endrin, dieldrin, heptachlor, since more than 50 years for combating agricultural pests and controlling disease vectors, especially malaria. The way in which pesticides are used in Africa caused serious environmental and health problems much more than elsewhere. These problems are represented by accumulation of organochlorine pesticide (OCP) residues in different environmental samples and hosting of at least 50,000 tons of obsolete pesticides, as well as tens of thousands of tons of contaminated soil. Within the framework of the Africa Stockpiles Program (ASP), huge quantities of pesticidal POPs have been completely or partially destroyed in a number of African countries (e.g. Egypt, Namibia, Niger, Senegal, Seychelles, South Africa, Sudan, Tanzania, Uganda, Zambia). At regional level (i.e. African Countries), a strategic plan for monitoring and getting rid of POPs in the continent should be set up and implemented through coordination between all governments. Among issues of top priorities are to find alternative non-combustion technologies for disposing obsolete pesticides, and to use alternative control measures for mosquitoes’ management and other vector-borne diseases.

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Laznik, Žiga, et Stanislav Trdan. « Možnosti okoljsko sprejemljivega zatiranja gospodarsko škodljivih polžev s poudarkom na rezultatih domačih raziskav zatiranja lazarjev (Arionidae) ». Acta agriculturae Slovenica 107, n^o 2 (26 octobre 2016) : 531. http://dx.doi.org/10.14720/aas.2016.107.2.23.

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Slugs from the Arionidae and Limacidae families are classified as an important economic agricultural pests. They are omnivorous animals. Slugs are sensitive to drying out, so they are active at night and in cloudy, rainy weather. They cause economic damage to the vegetables, crops, fruit trees, shrubs, grasses, herbs and ornamental plants. First reports of slugs control are dating from the early 20<sup>th</sup> century. This was followed by an important discovery in the year 1934 when in South Africa metaldehyde was discovered. This discovery has brought significant progress in the protection of plants against slugs. The next major step in the development of molluscicides was achieved with the discovery of carbamates. Due to the proven non-target effect of metaldehyde and other substances with molluscicidal activity researchers are looking for alternative solutions in the protection of plants against slugs. In this paper we present a variety of environmentally acceptable methods of slugs control, such as proper soil cultivation, beer trapping, barriers and the use of so-called electrical fences against slugs.

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KANTOR, Mihail, et Amnon LEVI. « Utilizing Genetic Resources and Precision Agriculture to Enhance Resistance to Biotic and Abiotic Stress in Watermelon ». Notulae Scientia Biologicae 10, n^o 1 (27 mars 2018) : 1–7. http://dx.doi.org/10.15835/nsb10110242.

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Originally from Africa, watermelon is a staple crop in South Carolina and rich source of important phytochemicals that promote human health. As a result of many years of domestication and selection for desired fruit quality, modern watermelon cultivars are susceptible to biotic and abiotic stress. The present review discusses how genetic selection and breeding combined with geospatial technologies (precision agriculture) may help enhance watermelon varieties for resistance to biotic and abiotic stress. Gene loci identified and selected in undomesticated watermelon accessions are responsible for resistance to diseases, pests and abiotic stress. Vegetable breeding programs use traditional breeding methodologies and genomic tools to introduce gene loci conferring biotic or abiotic resistance into the genome background of elite watermelon cultivars. This continuous approach of collecting, evaluating and identifying useful genetic material is valuable for enhancing genetic diversity and tolerance and combined with precision agriculture could increase food security in the Southeast.

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Martoni, Francesco, et Mark J. Blacket. « Description of an Australian endemic species of Trioza (Hemiptera : Triozidae) pest of the endemic tea tree, Melaleuca alternifolia (Myrtaceae) ». PLOS ONE 16, n^o 9 (22 septembre 2021) : e0257031. http://dx.doi.org/10.1371/journal.pone.0257031.

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Psyllids, also known as jumping plant lice, are phloem feeding Hemiptera that often show a strict species-specific relationship with their host plants. When psyllid-plant associations involve economically important crops, this may lead to the recognition of a psyllid species as an agricultural or horticultural pest. The Australian endemic tea tree, Melaleuca alternifolia (Maiden & Betche) Cheel., has been used for more than a century to extract essential oils and, long before that, as a traditional medicine by Indigenous Australian people. Recently, a triozid species has been found to damage the new growth of tea trees both in Queensland and New South Wales, raising interest around this previously undocumented pest. Furthermore, adults of the same species were also collected from Citrus plantations, leading to potential false-positive records of the exotic pest Trioza erytreae (Del Guercio 1918), the African Citrus psyllid. Here we describe for the first time Trioza melaleucae Martoni sp. nov. providing information on its distribution, host plant associations and phylogenetic relationships to other Trioza species. This work enables both morphological and molecular identification of this new species, allowing it to be recognized and distinguished for the first time from exotic pests as well as other Australian native psyllids. Furthermore, the haplotype network analysis presented here suggests a close relationship between Trioza melaleucae and the other Myrtaceae-feeding Trioza spp. from Australia, New Zealand, and Taiwan.

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Kleynhans, E., M. G. Barton, D. E. Conlong et J. S. Terblanche. « Population dynamics of Eldana saccharina Walker (Lepidoptera : Pyralidae) : application of a biophysical model to understand phenological variation in an agricultural pest ». Bulletin of Entomological Research 108, n^o 3 (8 août 2017) : 283–94. http://dx.doi.org/10.1017/s0007485317000712.

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AbstractUnderstanding pest population dynamics and seasonal phenology is a critical component of modern integrated pest-management programs. Accurate forecasting allows timely, cost-effective interventions, including maximum efficacy of, for example, biological control and/or sterile insect technique. Due to the variation in life stage-related sensitivity toward climate, insect pest population abundance models are often not easily interpreted or lack direct relevance to management strategies in the field. Here we apply a process-based (biophysical) model that incorporates climate data with life stage-dependent physiology and life history to attempt to predict Eldana saccharina life stage and generation turnover in sugarcane fields. Fitness traits are modelled at two agricultural locations in South Africa that differ in average temperature (hereafter a cold and a warm site). We test whether the life stage population structures in the field entering winter and local climate during winter directly affect development rates, and therefore interact to determine the population dynamics and phenological responses of E. saccharina in subsequent spring and summer seasons. The model predicts that: (1) E. saccharina can cycle through more generations at the warm site where fewer hours of cold and heat stress are endured, and (2) at the cold site, overwintering as pupae (rather than larvae) confer higher relative fitness and fecundity in the subsequent summer adult moths. The model predictions were compared with a large dataset of field observations from scouting records. Model predictions for larval presence (or absence) generally overlapped well with positive (or negative) scout records. These results are important for integrated pest management strategies by providing a useful foundation for future population dynamics models, and are applicable to a variety of agricultural landscapes, but especially the sugarcane industry of South Africa.

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Tembrock, Luke R., Alicia E. Timm, Frida A. Zink et Todd M. Gilligan. « Phylogeography of the Recent Expansion of Helicoverpa armigera (Lepidoptera : Noctuidae) in South America and the Caribbean Basin ». Annals of the Entomological Society of America 112, n^o 4 (17 avril 2019) : 388–401. http://dx.doi.org/10.1093/aesa/saz019.

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Abstract The Old World bollworm, Helicoverpa armigera (Hübner), is one of the most destructive agricultural pests worldwide. It was first recorded in Brazil in 2013, yet despite this recent introduction, H. armigera has spread throughout much of Latin America. Where H. armigera has become established, it is displacing or hybridizing with the congeneric New World pest Helicoverpa zea. In addition to the adaptive qualities that make H. armigera a megapest, such as broad range pesticide resistance, the spread of H. armigera in the New World may have been hastened by multiple introductions into South America and/or the Caribbean. The recent expansion of the range of H. armigera into the New World is analyzed herein using mtDNA of samples from South America, the Caribbean Basin, and the Florida Peninsula. Phylogeographic analyses reveal that several haplotypes are nearly ubiquitous throughout the New World and native range of H. armigera, but several haplotypes have limited geographic distribution from which a secondary introduction with Euro-African origins into the New World is inferred. In addition, host–haplotype correlations were analyzed to see whether haplotypes might be restricted to certain crops. No specialization was found; however, some haplotypes had a broader host range than others. These results suggest that the dispersal of H. armigera in the New World is occurring from both natural migration and human-mediated introductions. As such, both means of introduction should be monitored to prevent the spread of H. armigera into areas such as the United States, Mexico, and Canada, where it is not yet established.

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McLeod, A., et S. Coertze. « First Report of Phytophthora infestans on Petunia × hybrida in South Africa ». Plant Disease 90, n^o 12 (décembre 2006) : 1550. http://dx.doi.org/10.1094/pd-90-1550b.

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Phytophthora infestans is known worldwide as the destructive, late blight pathogen of potatoes and tomatoes. However, erratic reports dating back to 1856 also have shown it to be pathogenic on petunia (Petunia × hybrida), although it has not been regarded as an important pathogen on this host (4). Recently, reports from North America showed that P. infestans is of commercial importance in greenhouse-grown petunias (2), and that late blight-infected petunias may serve as inoculum to tomatoes growing in the same greenhouse (1,2). In the Western Cape Province of South Africa, two petunia samples were received at the Stellenbosch University Plant Disease Clinic in 2005 that showed symptoms resembling P. infestans infections. The two samples were from nurseries where petunias were either grown under shading nets or in a greenhouse. In the greenhouse-grown petunias, the presumptive late blight infections resulted in substantial losses to the grower. Symptoms included gray, slightly sunken leaf lesions with white sporulation mainly on the adaxial side of the leaves. Leaflets of the petunias were incubated in moist chambers, and sporangia sporulating from lesions were identified morphologically as being P. infestans (3). Subsequently, one isolate was cultured onto synthetic media by carefully transferring sporangia from a lesion with the tip of a bended glass rod onto wheat medium (120 g/L of crushed wheat seeds, blended, boiled and filtered through cheesecloth, plus 15 g of sucrose and agar). The identity of the culture was further confirmed through sequence analyses of the internal transcribed spacer regions (GenBank Accession No. DQ479409). The isolated P. infestans strain (STE-U 6134) has been submitted to the Stellenbosch University culture collection. Inoculum for the pathogenicity tests was produced by first flooding 14-day-old cultures with sterile distilled water to obtain a 2 × 104/ml sporangial suspension, followed by zoospore induction at 4°C. A mixture of petunia cultivars (n = 24) were spray inoculated to runoff with the zoospore induced sporangial suspension. Control plants were sprayed with sterile distilled water. Inoculated plants were incubated at 22 to 25°C and high relative humidity (≥93%) within perspex humidity chambers (60 × 30 × 60 cm) lined with a wet sheet of chromatography paper. The experiment was repeated twice. The first late blight symptoms similar to those of the submitted samples appeared 5 to 7 days after inoculation, with some lesions containing profuse white mycelia and sporangiophores typical for P. infestans. The pathogen was reisolated from the leaf lesions, completing Koch's postulate. To our knowledge, this is the first report of P. infestans causing damage on petunias in South Africa. Future studies should be aimed at investigating whether late blight-infected petunias provide an important source of inoculum for potatoes and tomatoes, which are widely grown in the Western Cape Province of South Africa. References: (1) M. C. Becktell et al. Plant Dis. 89:1000, 2005. (2) K. L. Deahl and D. K. Farel. Plant Dis. 87:1004, 2003. (3) D. C. Erwin and O. K. Ribeiro, Phytophthora Diseases Worldwide. The American Phytopathological Society St. Paul, MN, 1996. (4) J. M. Hirst and W. C. Moore. Phytophthora infestans on petunia and datura. Page 76 in: Plant Pathology-A Record of Current Work on Plant Diseases and Pests. Vol. 6. Ministry of Agriculture, Fisheries and Food Plant Pathology Laboratory, Harpenden, England, 1957.

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Botiabane, Moswane Precious, L. Zhou, I. B. Oluwatayo, Fakunle Olufemi Oyedokun et Akeem Adewale Oyelana. « Socioeconomic Analysis and Technical Efficiency among Smallholder Sorghum Farmers in GaMasemola Township of Limpopo Province, South Africa ». Journal of Economics and Behavioral Studies 9, n^o 6 (15 janvier 2018) : 17–25. http://dx.doi.org/10.22610/jebs.v9i6.2001.

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Sorghum farming group in South Africa is divided into the smallholder and business ranchers attributable to the distinctions in cultivar sizes, utility creation and production strategies. Sorghum is utilized primarily for sustenance and refreshments in Ga-Masemola (GM) town. Smallholder sorghum farmers in the town utilize some portion of their wage for recreation, goat and cows' compost are utilized as manures to enhance soil fruitfulness and increment sorghum yield, they rely upon precipitation water for the water system and they have no entrance to expansion administrations. The study distinguish and depict the socioeconomic characteristics of smallholder sorghum farmers in Ga-Masemola town; it looks at the causes of technical efficiency among smallholder sorghum ranchers in the town, and it recognizes and portrays difficulties confronted by smallholder sorghum farmers in the town. Essential information was gathered utilizing organized surveys and an example size of 48 smallholder sorghum farmers in the town was chosen. Cobb Douglas model was utilized to analyze the information or data gotten.The socioeconomic characteristics of smallholder sorghum farmers were:farming experience, age, sexual orientation, instructive level and family unit measure. The study indicates that the determinants of technical efficiency among smallholder sorghum farmers in Ga-Masemola town that were observed to be huge are the measure of land dedicated and the amount of seeds utilized. Farmers are confronting difficulties, for example, sicknesses, low capital, pests, separation to the homestead, absence of water and atmosphere (i.e. climate) changes.The study suggested and recommended that smallholder sorghum farmers in Ga-Masemola (GM) town require arable land to expand their production; they additionally require agriculture extension officers for training and spreading or disseminating information about inputs allocation. Besides, the smallholder farmers should be encouraged to utilize enhanced seeds varieties in order to expand their technical efficiency.

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Adom, M., K. O. Fening, M. K. Billah, D. D. Wilson, W. Hevi, V. A. Clottey, F. Ansah-Amprofi et A. Y. Bruce. « Pest status, bio-ecology and management of the false codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera : Tortricidae) and its implication for international trade ». Bulletin of Entomological Research 111, n^o 1 (17 juin 2020) : 17–30. http://dx.doi.org/10.1017/s0007485320000358.

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AbstractThe false codling moth (FCM), Thaumatotibia leucotreta (Lepidoptera: Tortricidae) is an insect pest which represents an important threat to the production and marketing of a wide range of agricultural crops in the African-Caribbean-Pacific (ACP) countries. The FCM reduces not only the yield and quality of the crop but also as a quarantine insect pest, restricts the trade of susceptible agricultural produce on the international market. In addition, little research has been conducted in the ACP countries on the bio-ecology and sustainable management of this pest, especially on vegetables for export. Thus, action-oriented research aimed at understanding the bio-ecology of this important pest is essential to achieve effective management. Various management interventions against this pest have been used in some parts of the world, especially in South Africa on citrus. Currently, farm sanitation is regarded as the key management strategy. Exploring and improving on other interventions such as Sterile Insect Technique, monitoring and mass trapping of male moths, augmentative biological control, use of bio-pesticides, protected cultivation and cold treatment may help to mitigate the expansion of FCM into other countries, especially in the European and Mediterranean Plant Protection Organization region where it has become a regulated insect pest since 2014. This review discussed the bio-ecology of FCM and highlighted some of the challenges and opportunities for its effective management and its implication for international trade, especially the export of chillies from the ACP countries into the European Union market which requires strict phytosanitary regulations.

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Karsten, Minette, Bettine Jansen van Vuuren, Adeline Barnaud et John S. Terblanche. « Population Genetics of Ceratitis capitata in South Africa : Implications for Dispersal and Pest Management ». PLoS ONE 8, n^o 1 (16 janvier 2013) : e54281. http://dx.doi.org/10.1371/journal.pone.0054281.

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Prinsloo, G. L. « A Complete Guide to Vegetable Pests in South AfricaA Complete Guide to Vegetable Pests in South Africaby D. Visser , Agricultural Research Council, Roodeplaat Vegetable and Ornamental Plant Institute, Pretoria. 2009. 316 pp. Price ; R320.00 ISBN 978-1-86849-445-3. » African Entomology 18, n^o 1 (mars 2010) : 217–19. http://dx.doi.org/10.4001/003.018.0123.

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Eimanifar, Amin, Johanna T. Pieplow, Alireza Asem et James D. Ellis. « Genetic diversity and population structure of two subspecies of western honey bees (Apis mellifera L.) in the Republic of South Africa as revealed by microsatellite genotyping ». PeerJ 8 (3 janvier 2020) : e8280. http://dx.doi.org/10.7717/peerj.8280.

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Apis mellifera scutellata and Apis mellifera capensis, two native subspecies of western honey bees in the Republic of South Africa (RSA), are important to beekeepers in their native region because beekeepers use these bees for honey production and pollination purposes. Additionally, both bees are important invasive pests outside of their native ranges. Recently, whole mitogenome sequencing and single nucleotide polymorphisms were used to study their genetic diversity. To add to our knowledge of the molecular ecology of both bees, we tested the ability of microsatellites to be used as a tool to discriminate between A.m. capensis and A.m. scutellata. We analyzed the genetic variability and overall population structure of both bee subspecies and hybrids of the two by genotyping individuals collected from RSA (N = 813 bees from 75 apiaries) at 19 microsatellite DNA loci. Overall, populations averaged between 9.2 and 11.3 alleles per locus, with unbiased heterozygosity values ranging from 0.81 to 0.86 per population. Bayesian clustering analyses revealed two distinct evolutionary units, though the results did not match those of earlier morphometric and molecular analyses. This suggests that the microsatellites we tested were not sufficient for subspecies identification purposes, especially for Cape and hybrid bees. Nevertheless, the microsatellite data highlight the considerable genetic diversity within both populations and a larger-than-expected hybridization zone between the natural distributions of A.m. capensis and A.m. scutellata.

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Russo, V., A. E. Strever et H. J. Ponstein. « Exploring sustainability potentials in vineyards through LCA ? Evidence from farming practices in South Africa ». International Journal of Life Cycle Assessment 26, n^o 7 (28 avril 2021) : 1374–90. http://dx.doi.org/10.1007/s11367-021-01911-3.

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Abstract Purpose Following the urgency to curb environmental impacts across all sectors globally, this is the first life cycle assessment of different wine grape farming practices suitable for commercial conventional production in South Africa, aiming at better understanding the potentials to reduce adverse effects on the environment and on human health. Methods An attributional life cycle assessment was conducted on eight different scenarios that reduce the inputs of herbicides and insecticides compared against a business as usual (BAU) scenario. We assess several impact categories based on ReCiPe, namely global warming potential, terrestrial acidification, freshwater eutrophication, terrestrial toxicity, freshwater toxicity, marine toxicity, human carcinogenic toxicity and human non-carcinogenic toxicity, human health and ecosystems. A water footprint assessment based on the AWARE method accounts for potential impacts within the watershed. Results and discussion Results show that in our impact assessment, more sustainable farming practices do not always outperform the BAU scenario, which relies on synthetic fertiliser and agrochemicals. As a main trend, most of the impact categories were dominated by energy requirements of wine grape production in an irrigated vineyard, namely the usage of electricity for irrigation pumps and diesel for agricultural machinery. The most favourable scenario across the impact categories provided a low diesel usage, strongly reduced herbicides and the absence of insecticides as it applied cover crops and an integrated pest management. Pesticides and heavy metals contained in agrochemicals are the main contributors to emissions to soil that affected the toxicity categories and impose a risk on human health, which is particularly relevant for the manual labour-intensive South African wine sector. However, we suggest that impacts of agrochemicals on human health and the environment are undervalued in the assessment. The 70% reduction of toxic agrochemicals such as Glyphosate and Paraquat and the 100% reduction of Chlorpyriphos in vineyards hardly affected the model results for human and ecotoxicity. Our concerns are magnified by the fact that manual labour plays a substantial role in South African vineyards, increasing the exposure of humans to these toxic chemicals at their workplace. Conclusions A more sustainable wine grape production is possible when shifting to integrated grape production practices that reduce the inputs of agrochemicals. Further, improved water and related electricity management through drip irrigation, deficit irrigation and photovoltaic-powered irrigation is recommendable, relieving stress on local water bodies, enhancing drought-preparedness planning and curbing CO2 emissions embodied in products.

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Misaka, Beatrice C., Everlyne N. Wosula, Philip W. Marchelo-d’Ragga, Trine Hvoslef-Eide et James P. Legg. « Genetic Diversity of Bemisia tabaci (Gennadius) (Hemiptera : Aleyrodidae) Colonizing Sweet Potato and Cassava in South Sudan ». Insects 11, n^o 1 (17 janvier 2020) : 58. http://dx.doi.org/10.3390/insects11010058.

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Bemisia tabaci (Gennadius) is a polyphagous, highly destructive pest that is capable of vectoring viruses in most agricultural crops. Currently, information regarding the distribution and genetic diversity of B. tabaci in South Sudan is not available. The objectives of this study were to investigate the genetic variability of B. tabaci infesting sweet potato and cassava in South Sudan. Field surveys were conducted between August 2017 and July and August 2018 in 10 locations in Juba County, Central Equatoria State, South Sudan. The sequences of mitochondrial DNA cytochrome oxidase I (mtCOI) were used to determine the phylogenetic relationships between sampled B. tabaci. Six distinct genetic groups of B. tabaci were identified, including three non-cassava haplotypes (Mediterranean (MED), Indian Ocean (IO), and Uganda) and three cassava haplotypes (Sub-Saharan Africa 1 sub-group 1 (SSA1-SG1), SSA1-SG3, and SSA2). MED predominated on sweet potato and SSA2 on cassava in all of the sampled locations. The Uganda haplotype was also widespread, occurring in five of the sampled locations. This study provides important information on the diversity of B. tabaci species in South Sudan. A comprehensive assessment of the genetic diversity, geographical distribution, population dynamics, and host range of B. tabaci species in South Sudan is vital for its effective management.

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Hinojosa, Leonardo, Alex Leguizamo, Carlos Carpio, Diego Muñoz, Camilo Mestanza, José Ochoa, Carmen Castillo et al. « Quinoa in Ecuador : Recent Advances under Global Expansion ». Plants 10, n^o 2 (4 février 2021) : 298. http://dx.doi.org/10.3390/plants10020298.

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Quinoa is a highly diverse crop domesticated in the Andean region of South America with broad adaptation to a wide range of marginal environments. Quinoa has garnered interest worldwide due to its nutritional and health benefits. Over the last decade, quinoa production has expanded outside of the Andean region, prompting multiple studies investigating the potential for quinoa cultivation in novel environments. Currently, quinoa is grown in countries spanning five continents, including North America, Europe, Asia, Africa, and Oceania. Here, we update the advances of quinoa research in Ecuador across different topics, including (a) current quinoa production situation with a focus on breeding progress, (b) traditional seed production, and (c) the impact of the work of the nongovernment organization “European Committee for Training and Agriculture” with quinoa farmers in Chimborazo province. Additionally, we discuss genetic diversity, primary pests and diseases, actions for adapting quinoa to tropical areas, and recent innovations in quinoa processing in Ecuador. Finally, we report a case study describing a participatory breeding project between Washington State University and the Association of Andean Seed and Nutritional Food Producers Mushuk Yuyay in the province of Cañar.

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Zingore, Kumbirai M., George Sithole, Elfatih M. Abdel-Rahman, Samira A. Mohamed, Sunday Ekesi, Chrysantus M. Tanga et Mohammed E. E. Mahmoud. « Global risk of invasion by Bactrocera zonata : Implications on horticultural crop production under changing climatic conditions ». PLOS ONE 15, n^o 12 (23 décembre 2020) : e0243047. http://dx.doi.org/10.1371/journal.pone.0243047.

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The peach fruit fly Bactrocera zonata (Saunders) (Diptera: Tephritidae) is an important invasive species causing substantial losses to the horticulture industry worldwide. Despite the severe economic impact caused by this pest in its native and invaded range, information on its potential range expansion under changing climate remains largely unknown. In this study, we employed maximum entropy (MaxEnt) modeling approach to predict the global potential climatic suitability of B. zonata under current climate and four Representative Concentration Pathways (RCPs) for the year 2050. Outputs from MaxEnt were merged with Spatial Production Allocation Model. A natural dispersal model using Gaussian dispersal kernel was developed. The Areas Under Curves generated by MaxEnt were greater than 0.92 for both current and future climate change scenarios, indicating satisfactory performances of the models. Mean temperature of the coldest quarter, precipitation of driest month and temperature seasonality significantly influenced the potential establishment of B. zonata. The models indicated high climatic suitability in tropical and subtropical areas in Asia and Africa, where the species has already been recorded. Suitable areas were predicted in West, East and Central Africa and to a lesser extent in Central and South America. Future climatic scenarios models, RCP 4.5 and 8.5 show significant potential range expansion of B. zonata in Western Sahara, while RCP 4.5 highlighted expansion in Southern Africa. Contrarily, RCP 2.6 showed considerable decrease in B. zonata range expansion in Central, East and West Africa. There was increased climatic suitability of B. zonata in Egypt and Middle East under RCP 6.0. The dispersal model revealed that B. zonata could spread widely within its vicinity with decreasing infestation rates away from the source points. Our findings can help to guide biosecurity agencies in decision-making and serve as an early warning tool to safeguard against the pest invasion into unaffected areas.

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Wei, Jiufeng, Xiaozhou Li, Yunyun Lu, Ling Zhao, Hufang Zhang et Qing Zhao. « Modeling the Potential Global Distribution of Phenacoccus madeirensis Green under Various Climate Change Scenarios ». Forests 10, n^o 9 (6 septembre 2019) : 773. http://dx.doi.org/10.3390/f10090773.

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The Madeira mealybug, Phenacoccus madeirensis Green, is a serious invasive pest that does significant damage to more than 120 genera of host plants from 51 families in more than 81 countries. However, the potential distribution range of this pest is unclear, which could hamper control and eradication efforts. In the current study, MaxEnt models were developed to forecast the current and future distribution of the Madeira mealybug around the world. Moreover, the future potential distribution of this invasive species was projected for the 2050s and 2070s under three different climate change scenarios (HADGEM2-AO, GFDL-CM3, and MIROC5) and two representative concentration pathways (RCP-2.6 and RCP-8.5). The final model indicates that the Madeira mealybug has a highly suitable range for the continents of Asia, Europe, and Africa, as well as South America and North America, where this species has already been recorded. Potential expansions or reductions in distribution were also simulated under different future climatic conditions. Our study also suggested that the mean temperature of the driest quarter (Bio9) was the most important factor and explained 46.9% of the distribution model. The distribution model from the current and future predictions can enhance the strategic planning of agricultural and forestry organization by identifying regions that will need to develop integrated pest management programs to manage Madeira mealybug, especially for some highly suitable areas, such as South Asia and Europe. Moreover, the results of this research will help governments to optimize investment in the control and management of the Madeira mealybug by identifying regions that are or will become suitable for infestations.

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Nkwala, Alfiery Laurel Djomnang, Franklin Simo Talla, Charly Oumarou Ngoute, Sévilor Kekeunou, Alain Christel Wandji, Marcelle Mbajoun Nzike, Alain Simeu Noutchom et Mpoame Mbida. « Morphology, development, and reproduction of Eyprepocnemis plorans ibandana (Orthoptera : Acrididae) in South Cameroon rainforests ». Journal of Orthoptera Research 28, n^o 2 (3 septembre 2019) : 145–54. http://dx.doi.org/10.3897/jor.28.33370.

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Eyprepocnemis plorans ibandana is a very common grasshopper species in open environments and agricultural systems of tropical Africa. It is a pest that significantly benefits from forest degradation in southern Cameroon, hence the need to study the bioecology of this subspecies. We studied the reproduction as well as the morphological characteristics and development times of the post-embryonic instars of E. p. ibandana. Sixty-one adult pairs were obtained from sixth instar nymphs caught in grassy vegetation in the Nkolbisson area (Yaoundé) and bred in the laboratory. After hatching, the first instar nymphs were individually placed in cages and fed every two days using fresh leaves of Manihot esculenta. The postembryonic development of E. p. ibandana took six instars in the male and six to seven instars in the female. Mean nymphal development took 79.16 ± 0.51 days in males, 89.93 ± 0.58 days in 6 instar females and 94.96 ± 1.22 days in 7 instar females. The survival rate of the first instar was low (53%). However, from the second instar on the survival rate was very high (> 87%). Sexual dimorphism is distinct in adults, fifth and sixth nymphal instars. Adults of E. p. ibandana took on average 32.57 ± 3.88 days to start mating, and mating lasted 2.12 h on average (1–3 h). Oviposition took place on average 52.03 ± 5 days after first mating; each female deposited one to eleven oothecae with an average of 34.93 ± 2.37 eggs per ootheca. Our study provides important information for the control of this subspecies in southern Cameroon.

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LANGLEY, JETHRO, MORGAN CORNWALL, CHANTÉ POWELL, CARLO COSTA, ELLEUNORAH ALLSOPP, SIMON VAN NOORT, ERIC GUILBERT et BARBARA VAN ASCH. « First report of the lace bug Neoplerochila paliatseasi (Rodrigues, 1981) (Hemiptera : Tingidae) infesting cultivated olive trees in South Africa, and its complete mitochondrial sequence ». Zootaxa 4722, n^o 5 (16 janvier 2020) : 443–62. http://dx.doi.org/10.11646/zootaxa.4722.5.3.

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Olive lace bugs are small phytophagous Hemipteran insects known to cause agricultural losses in olive production in South Africa. Plerochila australis (Distant, 1904) has been reported as the species responsible for damage to olive trees; however, the diversity of olive lace bug species in the region has lacked attention. Adult olive lace bugs were collected incidentally from wild and cultivated olive trees in the Western Cape Province, and identified as P. australis and Neoplerochila paliatseasi (Rodrigues, 1981). The complete mitochondrial genome of a representative specimen of N. paliatseasi was sequenced, and used for comparative mitogenomics and phylogenetic reconstruction within the family. Furthermore, the value of DNA barcodes for species identification in Tingidae was assessed using genetic clustering and estimates of genetic divergence. The patterns of genetic clustering and genetic divergence of COI sequences supported the morphological identification of N. paliatseasi, and the utility of DNA barcoding methods in Tingidae. The complete mitogenome sequence had the typical Metazoan gene content and order, including 13 PCGs, 22 tRNAs, two rRNAs, and an AT-rich non-coding region. A+T content was high, as commonly found in Tingidae. The phylogenetic reconstruction recovered Agramma hupehanum (Drake & Maa 1954) as basal to Tingini, and as a sister species to N. paliatseasi. Stephanitis Stål 1873 and Corythucha Stål 1873 were monophyletic, but Metasalis populi (Takeya 1932) was not recovered as sister to Tingis cardui (Linnaeus 1746), as expected. The mitochondrial phylogeny of the family Tingidae has been recovered inconsistently across different studies, possibly due to sequence heterogeneity and high mutation rates. Species diversity of olive lace bugs in South Africa was previously underestimated. The presence of P. australis was confirmed in both wild and cultivated olives, and N. paliatseasi is reported in cultivated olives for the first time. These results warrant further investigation on the diversity and distribution of olive lace bugs in the Western Cape to inform pest control strategies.

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Gahatraj, S., S. Tiwari, S. Sharma et L. Kafle. « Fall Armyworm, Spodoptera frugiperda (Lepidoptera : Noctuidae) : A recent threat and future management strategy in Nepal ». Agricultural Science and Technology 12, n^o 2 (juin 2020) : 157–64. http://dx.doi.org/10.15547/ast.2020.02.027.

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Abstract. Fall Armyworm (FAW), Spodoptera frugiperda, is an invasive pest of maize including other cultivated crops such as rice, wheat, and many other vegetables. This invasive species was initially noticed in North-America and later reported in many countries of Africa in early 2016. In South Asia, this has been reported for the first time in India followed by Srilanka in 2018 and Bangladesh, China, Taiwan and Nepal in 2019. It is polyphagous in nature and damage has been reported in more than 80 plant species. The loss has to lead up to 50-80% in maize in severe situation. FAW is a distant flyer and can fly more than 100 km in a night and spread well in crop fields. As this pest is already invasive in many states of India and the likelihood of entry and spreading in Nepal is higher because of the open border between the countries and flexible government quarantine policy. The great socio-economic loss has been forecasted once this pest has received invasive status in Nepal. Recently, this crop has been confirmed by Nepal Agricultural Research Council (NARC) in Gaidakot area of Nawalpur district, Nepal and has been noticed in almost all parts of Nepal such as Sidhuli, Chitwan, Nawalparasi, Tanahun and Rupendehi districts. However, this information has not been endorsed by Nepal Plant Protection Office (NPPO), an official invasive species endorsing organization in Nepal. This species is spreading rapidly in maize growing areas and significant losses have been reported in maize crop by the farmers. The regular scouting, surveillance, and monitoring can be suggested to evaluate the pest status in the crop field. Habitat manipulation with the deployment of deterring crops ‘push’ such as desmodium (Desmodium uncinatum) and pest-attracting crop ‘pull’ such as Napier (Pennisetum purpureum) and Sudan grass (Sorghum vulgare sudanense) is suggested in a ‘push-pull strategy’, the most popular and successful method of FAW management in the maize field. Field sanitation, and conserving pest’s natural enemies are other integrated approaches. However, in a commercial maize field, a group of ‘soft’ and selective chemicals have been suggested for immediate control of this pest. This review compiled the recent informations available on FAW and is useful for farmers, researchers and policy makers to draw a roadmap for the future FAW management in Nepal.

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Grové, T., P. S. Schoeman et M. S. De Beer. « ARTHROPOD PESTS OF LITCHI IN SOUTH AFRICA ». Acta Horticulturae, n^o 1029 (avril 2014) : 409–16. http://dx.doi.org/10.17660/actahortic.2014.1029.52.

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Klein, Igor, Natascha Oppelt et Claudia Kuenzer. « Application of Remote Sensing Data for Locust Research and Management—A Review ». Insects 12, n^o 3 (9 mars 2021) : 233. http://dx.doi.org/10.3390/insects12030233.

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Recently, locust outbreaks around the world have destroyed agricultural and natural vegetation and caused massive damage endangering food security. Unusual heavy rainfalls in habitats of the desert locust (Schistocerca gregaria) and lack of monitoring due to political conflicts or inaccessibility of those habitats lead to massive desert locust outbreaks and swarms migrating over the Arabian Peninsula, East Africa, India and Pakistan. At the same time, swarms of the Moroccan locust (Dociostaurus maroccanus) in some Central Asian countries and swarms of the Italian locust (Calliptamus italicus) in Russia and China destroyed crops despite developed and ongoing monitoring and control measurements. These recent events underline that the risk and damage caused by locust pests is as present as ever and affects 100 million of human lives despite technical progress in locust monitoring, prediction and control approaches. Remote sensing has become one of the most important data sources in locust management. Since the 1980s, remote sensing data and applications have accompanied many locust management activities and contributed to an improved and more effective control of locust outbreaks and plagues. Recently, open-access remote sensing data archives as well as progress in cloud computing provide unprecedented opportunity for remote sensing-based locust management and research. Additionally, unmanned aerial vehicle (UAV) systems bring up new prospects for a more effective and faster locust control. Nevertheless, the full capacity of available remote sensing applications and possibilities have not been exploited yet. This review paper provides a comprehensive and quantitative overview of international research articles focusing on remote sensing application for locust management and research. We reviewed 110 articles published over the last four decades, and categorized them into different aspects and main research topics to summarize achievements and gaps for further research and application development. The results reveal a strong focus on three species—the desert locust, the migratory locust (Locusta migratoria), and the Australian plague locust (Chortoicetes terminifera)—and corresponding regions of interest. There is still a lack of international studies for other pest species such as the Italian locust, the Moroccan locust, the Central American locust (Schistocerca piceifrons), the South American locust (Schistocerca cancellata), the brown locust (Locustana pardalina) and the red locust (Nomadacris septemfasciata). In terms of applied sensors, most studies utilized Advanced Very-High-Resolution Radiometer (AVHRR), Satellite Pour l’Observation de la Terre VEGETATION (SPOT-VGT), Moderate-Resolution Imaging Spectroradiometer (MODIS) as well as Landsat data focusing mainly on vegetation monitoring or land cover mapping. Application of geomorphological metrics as well as radar-based soil moisture data is comparably rare despite previous acknowledgement of their importance for locust outbreaks. Despite great advance and usage of available remote sensing resources, we identify several gaps and potential for future research to further improve the understanding and capacities of the use of remote sensing in supporting locust outbreak- research and management.

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Pons Batugal. « International Coconut Genetic Resources Network (COGENT) : Its history and achievements ». CORD 21, n^o 02 (1 juin 2005) : 34. http://dx.doi.org/10.37833/cord.v21i02.408.

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The International Coconut Genetic Resources Network (COGENT) is a global research network organized by the International Plant Genetic Resources Institute (IPGRI) in 1992 with support from member countries, the Consultative Group on International Agricultural Research (CGIAR), partner institutions, donor agencies, and by regional and international development organizations. In the last 12 years, COGENT has been fully operational with 38 member coconut producing countries in five regions (South Asia; Southeast and East Asia; South Pacific; Africa and the Indian Ocean; and Latin America and the Caribbean). It has successfully developed and disseminated to coconut breeders and curators worldwide the International Coconut Genetic Resources Database (CGRD). The CGRD contains characterization data and some pictures of 1,416 accessions which are conserved by national programmes in 28 sites in 23 countries. To further secure conserved germplasm, a COGENT multi-site International Coconut Genebank has been established to conserve 200 important accessions in each region. Coconut varieties with multi-purpose uses are being identified, documented and promoted. The performance of promising 38 high-yielding hybrids are being evaluated in a multilocation trial involving four African and three Latin America/Caribbean countries to identify suitable varieties and hybrids for resource-poor farmers. Farmers’ varietal preferences in 15 countries are being evaluated. Diversity-linked income-generating activities are being used as a strategy to promote in situ and on-farm conservation and germplasm utilization have been initiated in 15 countries. Protocols for in vitro embryo culture, cryopreservation, morphometric and molecular marker-based methods for locating and characterizing diversity; pest risk assessment and germplasm health management are being developed, tested and upgraded. Strategies and techniques for farmer participatory research, collecting, characterization and ex situ and in situ conservation are being refined. To strengthen the coconut research capability of COGENT member countries, the COGENT Secretariat and IPGRI have organized 39 country need assessment missions and conducted 41 workshops and meetings involving 994 coconut researchers to share information and technologies, discuss issues and common problems and opportunities and how to address them; conducted 40 training courses involving 765 participants from 41 countries; supported 274 research and training/capacity building activities in 30 countries; and led the establishment of the Global Coconut Research for Development Programme (PROCORD). IPGRI and COGENT's current priority involves the further promotion of more effective conservation and use of coconut genetic resources, both regionally and globally.

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Nesamari, R., T. A. Coutinho et J. Roux. « Diseases and pests of Encephalartos species in South Africa ». South African Journal of Botany 98 (mai 2015) : 214. http://dx.doi.org/10.1016/j.sajb.2015.03.168.

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Weyl, Philip, Abdul Rehman et Kazam Ali. « The Host Range of the Stem-Boring Weevil, Listronotus setosipennis (Coleoptera : Curculionidae) Proposed for the Biological Control of Parthenium hysterophorus (Asteraceae) in Pakistan ». Insects 12, n^o 5 (17 mai 2021) : 463. http://dx.doi.org/10.3390/insects12050463.

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Parthenium, or Parthenium hysterophorus, has extended its range in Pakistan throughout Punjab and into Khyber Pakhtunkhwa, the Federally Administrated Tribal Areas, Azad Jammu and Kashmir, and Sindh Provinces. Without control measures against parthenium, the negative impacts of this weed will go unchecked having deleterious effects on native biodiversity, human and animal health, as well as crop productivity. The weevil Listronotus setosipennis was obtained and imported from the Plant Health and Protection of the Agricultural Research Council (ARC-PHP), in Cedara, South Africa, in April 2019. A total of 22 plant species or cultivars in the Asteraceae family were assessed during no-choice oviposition tests in Pakistan. During these tests, the only plant species accepted for oviposition were the 10 cultivars of Helianthus annuus that are grown in Pakistan. All cultivars were thus tested for development of L. setosipennis from egg to adult. Only three cultivars were able to support some larval development, but at such low levels that it is unlikely to be the basis of a viable population. To support this, a risk assessment was conducted to ascertain the probability of L. setosipennis being able to sustain viable populations in the field, the results of which concur with native (Argentina) and introduced (Australia) field host-range information where L. setosipennis has never been recorded as a pest of sunflowers. The results of laboratory-based host-range trials, together with host records from its native and introduced range, indicate that L. setosipennis is sufficiently specific to parthenium and is thus suitable for release in Pakistan.

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Whittles, Lilith K., et Xavier Didelot. « Epidemiological analysis of the Eyam plague outbreak of 1665–1666 ». Proceedings of the Royal Society B : Biological Sciences 283, n^o 1830 (11 mai 2016) : 20160618. http://dx.doi.org/10.1098/rspb.2016.0618.

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Plague, caused by the bacterium Yersinia pestis , is one of the deadliest infectious diseases in human history, and still causes worrying outbreaks in Africa and South America. Despite the historical and current importance of plague, several questions remain unanswered concerning its transmission routes and infection risk factors. The plague outbreak that started in September 1665 in the Derbyshire village of Eyam claimed 257 lives over 14 months, wiping out entire families. Since previous attempts at modelling the Eyam plague, new data have been unearthed from parish records revealing a much more complete record of the disease. Using a stochastic compartmental model and Bayesian analytical methods, we found that both rodent-to-human and human-to-human transmission played an important role in spreading the infection, and that they accounted, respectively, for a quarter and three-quarters of all infections, with a statistically significant seasonality effect. We also found that the force of infection was stronger for infectious individuals living in the same household compared with the rest of the village. Poverty significantly increased the risk of disease, whereas adulthood decreased the risk. These results on the Eyam outbreak contribute to the current debate on the relative importance of plague transmission routes.

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Grové, T., et M. S. De Beer. « Insect pests affecting the production of mango in South Africa ». Acta Horticulturae, n^o 1183 (novembre 2017) : 297–304. http://dx.doi.org/10.17660/actahortic.2017.1183.43.

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Wickins, Peter. « Agricultural revolution in South Africa ». South African Journal of Economic History 4, n^o 2 (septembre 1989) : 109–30. http://dx.doi.org/10.1080/20780389.1989.10417165.

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Lange, C. E., et D. A. Streett. « SUSCEPTIBILITY OF ARGENTINE MELANOPLINES (ORTHOPTERA : ACRIDIDAE) TO ENTOMOPOXVIRUSES (ENTOMOPOXVIRINAE) FROM NORTH AMERICAN AND AFRICAN GRASSHOPPERS ». Canadian Entomologist 125, n^o 6 (décembre 1993) : 1127–29. http://dx.doi.org/10.4039/ent1251127-6.

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Grasshoppers are responsible for considerable agricultural losses in different parts of Argentina (C.O.P.R. 1982). Most of the pest species in Argentina belong to the subfamily Melanoplinae. It is generally accepted that South American melanoplines are derived from a nearctic stock that crossed the Panamanian land bridge (Carbonell 1977). The genus Dichroplus Stål is one of the largest genera within the South American Melanoplinae (Ronderos and Cigliano 1990). Dichroplus contains several economically important species and is believed to be closely related to the nearctic genus Melanoplus Stål (Vickery 1989).

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L. STUBBINS, FRANCESCA, PAULA AGUDELO, FRANCIS P. F. REAY-JONES et JEREMY K. GREENE. « Agamermis (Nematoda : Mermithidae) Infection in South Carolina Agricultural Pests ». Journal of Nematology 48, n^o 4 (2016) : 290–96. http://dx.doi.org/10.21307/jofnem-2017-037.

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Mnguni, Simphiwe. « Seasonal Population Abundance of Bactrocera Dorsalis Hendel (Diptera : Tephritidae) in Selected Districts of Northern KwaZulu Natal, South Africa ». Journal of Environmental and Agricultural Studies 2, n^o 1 (7 juin 2021) : 79–84. http://dx.doi.org/10.32996/jeas.2021.2.1.8.

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The fruitfly Bactrocera dorsalis is an economically important pest that requires management for the sustainability of agriculture in South Africa. This pest has spread from the country's Northern parts within a decade, where it has completely established and spread to other neighbouring provinces. The pest spreads at various rates due to different factors given biotic and abiotic factors. Understanding factors that influence pest prevalence will assist with practical management strategies. Temperature is one of the factors that assist the invasive potential of B. dorsalis. KwaZulu Natal province is among the hotspot provinces in the country besides Limpopo and Mpumalanga. Trap catches in Northern KwaZulu Natal, uMkhanyakude and King Cetshwayo districts show that the seasonal populations of B. dorsalis are continuously present all year round, even with the application of management options to reduce pest populations. Host availability plays a significant role in the invasion and total outcompeting of other native fruitflies e.g. Ceratitis punctata.

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Williams, Miesha J. « Discounted Agricultural Growth in South Africa ». Review of Black Political Economy 44, n^o 3-4 (janvier 2017) : 353–62. http://dx.doi.org/10.1007/s12114-017-9262-0.

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Phophi, Mutondwa Masindi, Paramu Mafongoya et Shenelle Lottering. « Perceptions of Climate Change and Drivers of Insect Pest Outbreaks in Vegetable Crops in Limpopo Province of South Africa ». Climate 8, n^o 2 (6 février 2020) : 27. http://dx.doi.org/10.3390/cli8020027.

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Vegetable production is a source of income for smallholder farmers in Limpopo Province, South Africa. Vegetable production is constrained by the negative impacts of climate change and pests. This study assessed farmers’ awareness of climate change, farmers’ knowledge of insect pests and factors that influence insect pests’ prevalence. The data were collected using quantitative and qualitative methods. The data were subjected to descriptive and bivariate analysis. About 84.5% of smallholder farmers were aware of climate change. Late rainfall (24.4%), long dry spells (15%) and increased drought frequency (19.4%) were highlighted as dominant indicators of climate change by farmers. Aphids (22.2%), Bagrada hilaris (12.5%) and Spodoptera frugiperda (10.2%) were the most prevalent insect pests within the Vhembe District. Warmer winters, dry spells and high temperatures were perceived by farmers to influence insect pests’ prevalence within the district. It can be concluded that farmers are aware of climate change and climatic factors influencing pest prevalence within the district. Pest risk maps are needed to improve the preparedness of the government and farmers in controlling insect pests under changing climates.

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Chitiga, M., T. Kandiero et P. Ngwenya. « Agricultural trade policy reform in South Africa ». Agrekon 47, n^o 1 (mars 2008) : 76–101. http://dx.doi.org/10.1080/03031853.2008.9523791.

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Frank, Deon. « AGRICULTURAL COMMODITY FUTURES MARKETS IN SOUTH AFRICA ». Agrekon 31, n^o 4 (décembre 1992) : 313–20. http://dx.doi.org/10.1080/03031853.1992.9524706.

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Gandidzanwa, Colleta, Frikkie Liebenberg, Ferdi Meyer et Beatrice Conradie. « Quality adjusting agricultural machinery in South Africa ». Agrekon 58, n^o 1 (2 janvier 2019) : 42–52. http://dx.doi.org/10.1080/03031853.2018.1545682.

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Pauw, Kalie, Scott Mcdonald et Cecilia Punt. « Agricultural efficiency and welfare in South Africa ». Development Southern Africa 24, n^o 2 (juin 2007) : 309–33. http://dx.doi.org/10.1080/03768350701327236.

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