CABI Africa

Nairobi, Kenya

CABI Africa

Nairobi, Kenya
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Wilson J.R.U.,South African National Biodiversity Institute | Wilson J.R.U.,Stellenbosch University | Gairifo C.,Stellenbosch University | Gairifo C.,University of Lisbon | And 20 more authors.
Diversity and Distributions | Year: 2011

Aim Many Australian Acacia species have been planted around the world, some are highly valued, some are invasive, and some are both highly valued and invasive. We review global efforts to minimize the risk and limit the impact of invasions in this widely used plant group. Location Global. Methods Using information from literature sources, knowledge and experience of the authors, and the responses from a questionnaire sent to experts around the world, we reviewed: (1) a generalized life cycle of Australian acacias and how to control each life stage, (2) different management approaches and (3) what is required to help limit or prevent invasions. Results Relatively few Australian acacias have been introduced in large numbers, but all species with a long and extensive history of planting have become invasive somewhere. Australian acacias, as a group, have a high risk of becoming invasive and causing significant impacts as determined by existing assessment schemes. Moreover, in most situations, long-lived seed banks mean it is very difficult to control established infestations. Control has focused almost exclusively on widespread invaders, and eradication has rarely been attempted. Classical biological control is being used in South Africa with increasing success. Main conclusions A greater emphasis on pro-active rather than reactive management is required given the difficulties managing established invasions of Australian acacias. Adverse effects of proposed new introductions can be minimized by conducting detailed risk assessments in advance, planning for on-going monitoring and management, and ensuring resources are in place for long-term mitigation. Benign alternatives (e.g. sterile hybrids) could be developed to replace existing utilized taxa. Eradication should be set as a management goal more often to reduce the invasion debt. Introducing classical biological control agents that have a successful track-record in South Africa to other regions and identifying new agents (notably vegetative feeders) can help mitigate existing widespread invasions. Trans-boundary sharing of information will assist efforts to limit future invasions, in particular, management strategies need to be better evaluated, monitored, published and publicised so that global best-practice procedures can be developed. © 2011 Blackwell Publishing Ltd.

Wright H.J.,CABI Inc | Ochilo W.,CABI Africa | Pearson A.,Rothamsted Research | Pearson A.,Lancaster University | And 6 more authors.
Journal of Agricultural and Food Information | Year: 2016

Plant pests cause crop losses of 30–40%, contributing significantly to global food insecurity. The Plantwise program works alongside national agricultural extension services, who advise smallholder farmers on plant health issues and collect data on problems they face. In a 1-year pilot, Plantwise tested the use of information and communication technologies (ICT)—tablets and short message service (SMS)—with 60 Kenyan extension workers. They were able to assist more farmers with better advice, had significantly improved access to plant health information, valued being able to ask their peers for advice, and dramatically improved the quality and speed of the data they collected. © 2016 The Author(s). Published with license by Taylor & Francis.

Flood J.,CABI E UK | Day R.,CABI Africa
Food Security | Year: 2016

Up to 80 % of global commodity production comes from smallholdings of less than 0.5 ha. Yet commodity crops may be a substantial proportion of a country’s exports, and feed into global supply networks. Pest risks thus have consequences at local, national and global levels. We consider three categories of risk in global commodity networks: introduction of pests to new areas, upsurges of established pests and the risks arising from management efforts. In each category we provide case studies and examples, and consider policy options. Increased travel, trade and transport increase the risks of introduction. Commodity specific biosecurity plans are required for preventing introductions, including analysis of the specific risks (pest pathways) and preparation of emergency responses. Regional and international cooperation is essential. Upsurges can be caused by crop management, evolution of new strains, and environment change. National systems must be responsive to detect problems and address them quickly. Capacity building for surveillance and diagnostics, and the development and dissemination of integrated pest management methods are needed. Investment in research and extension for the agricultural sector is vital. Risks linked with management efforts, specifically, the risk from agrochemicals are considered. Concerns in developed countries over food safety and environmental damage can place constraints on pest management. Failure to comply leads to loss of markets and buyer confidence. Policies that favour lower-risk pest management methods are needed, but are often lacking. © 2015, The Author(s).

Prasad V.L.,Indian International Crops Research Institute for the Semi Arid Tropics | Bezkorowajnyj P.G.,Indian International Crops Research Institute for the Semi Arid Tropics | Nigam S.N.,Indian International Crops Research Institute for the Semi Arid Tropics | Hanson J.,Forage Diversity at ILRI | Romney D.,CABI Africa
Outlook on Agriculture | Year: 2011

As part of a three-year project focusing on improving the livelihoods of poor livestock keepers by improving the availability of fodder, new groundnut varieties were tested, incorporating participatory rural appraisal (PRA), rapid rural appraisal (RRA), focus group discussions (FGDs) and field days as learning platforms. These approaches had limitations in addressing the complexity of the groundnut farming system and therefore constraints to the uptake of improved varieties continued to elude solution. The potential of a multi-stakeholder approach to gain a broader view of how novelty and innovation occur in a farming system was then recognized. Interactions among a range of actors including, among others, traders, oilseed merchants and private seed companies, were facilitated within a process of action and reflective learning. As a result, new constraints to innovation in groundnut varieties were identified and ways of overcoming them were noted. Documentation and analysis of the type and quality of linkages between the actors in the system helped to catalogue the process, and the platform thus created provided the actors with an opportunity to learn from each other. The lessons and implications are discussed.

Egonyu J.P.,National Coffee Research Institute | Baguma J.,National Coffee Research Institute | Ogari I.,National Coffee Research Institute | Ahumuza G.,National Coffee Research Institute | And 7 more authors.
Biological Control | Year: 2015

The coffee twig borer (Xylosandrus compactus Eichhoff) is an economically important pest of Robusta coffee in Uganda. In this study, a formicid ant, Plagiolepis sp., found in X. compactus galleries at the National Coffee Research Institute in 2014, was evaluated for potential to provide biological control of the twig borer. In a Petri dish feeding bioassay, Plagiolepis sp. preyed on all stages of X. compactus except adults within 24 h. In field bioassays where Plagiolepis sp. was caged over X. compactus-infested twigs for one month in muslin sleeves, the predator colonized pest galleries and eliminated all life stages of X. compactus as opposed to the untreated control. In a survey of Plagiolepis sp. in 11 districts of eastern, central and western Uganda, the ant was present in nine of the districts with highest levels of colonization (over 18%) of X. compactus galleries in Luwero district in the central Lake Victoria crescent agroecological zone. These results appear to confirm that Plagiolepis sp. is an indigenous predator of X. compactus which invades pest galleries and feeds on the pest in the field. For prospective utilization of Plagiolepis sp. as a biological control agent of X. compactus, studies on the biology of Plagiolepis sp., its mass rearing protocols and factors favoring its proliferation in the field are highly recommended. © 2015 Elsevier Inc.

McKay F.,South American Biological Control Laboratory | Gandolfo D.,South American Biological Control Laboratory | Witt A.B.R.,CABI Africa
African Entomology | Year: 2012

Invasive Prosopis species (Leguminosae) (mesquite) pose a significant threat to biodiversity, pasture production and water resources in South Africa. In an attempt to contain the spread of this noxious weed the South African authorities have supported the introduction of host-specific and damaging seed-feeding biocontrol agents. In order to increase seed losses caused by existing agents, surveys were undertaken in Argentina and a seed-feeding weevil Coelocephalapion gandolfoi Kissinger (Coleoptera: Brentidae: Apioninae) identified. Aspects of the biology and the host range of this seed-feeding weevil were studied in Argentina and South Africa to evaluate its potential as a biocontrol agent. The period from oviposition to adult emergence was c. 40 days. The duration of the stages was: 1120 days for eggs, 2540 days for larvae, and 616 days for pupae. Field surveys found that the beetle was responsible for 51 % of the seed damage on P. flexuosa. The host range of C. gandolfoi was restricted to Prosopis species in the section Algarobia. Oviposition and feeding preference for Prosopis species native to Argentina and P. glandulosa from North America was very high. We consider C. gandolfoi to be a good candidate for the biological control of invasive Prosopis species in South Africa.

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