African Entomology - Volume 22, Issue 2, 2014
Volumes & issues
Volume 22, Issue 2, 2014
Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) : a new threat to tomato production in sub-Saharan Africa : short communicationsSource: African Entomology 22, pp 441 –444 (2014)More Less
In sub-SaharanAfrica, vegetable crops are an essential component of sustainable development, with a significant contribution to food security and nutritional balance, but also an important source of income for resource-poor growers, especially in urban and peri-urban areas (FAO 2012). However, a major constraint to growing field horticultural crops is the reduction in yield and quality caused by insect pests by direct feeding or as plant disease vectors (James et al. 2010; Ekesi et al. 2011). Chemical control is the main control strategy implemented by growers to cope with insect pests (Ngowi et al. 2007; Grzywacz et al. 2010). Extensive and sometimes inappropriate use of chemical insecticides to control insect pests increases production costs and negatively impacts food safety (residues), human health and environment, especially biodiversity and beneficial arthropods (Desneux et al. 2007; Biondi et al. 2012). The implementation of effective and ecologically-sound integrated pest management (IPM) strategies is needed to develop sustainable vegetable production.
Source: African Entomology 22, pp 445 –447 (2014)More Less
Bactrocera invadens Drew, Tsuruta & White, 2005 (Diptera: Tephritidae) is an invasive fruit fly pest of Asian origin that was detected for the first time on the African continent in 2003 (Drew et al. 2005; Lux et al. 2003). The pest has spread rapidly since and is now established in several sub-Saharan countries (De Meyer et al. 2012). B. invadens responds to the male lure methyl eugenol (ME), (Lux et al. 2003) which is used for monitoring and control of the pest. Attraction of B. invadens to ME has to date not been quantified, although such information has been previously documented for Bactrocera dorsalis (Hendel), a close relative of B. invadens (Metcalf et al. 1975; Shelly et al. 2010). The objectives of the study were therefore to quantify the sensitivity of B. invadens to ME using mark-release-recapture techniques.
Source: African Entomology 22, pp 448 –453 (2014)More Less
Ants are almost ubiquitous, exhibit high species diversity and are functionally important insects. Thanks to these traits and the large numbers easily collected by pitfall trapping, ants have been frequently used in biodiversity and conservation studies (e.g. Samways 2005; Schoeman & Foord 2012) and as indicator species in rehabilitation projects (Majer & De Kock 1992; Andersen & Majer 2004; van Hamburg et al. 2004; Netshilaphala et al. 2005). Nevertheless, as with any indicator taxon, knowledge of distributions, patterns of seasonal activity and abundance is essential to make insightful inferences from differences in trap catches. Since the ant fauna of the arid regions of South Africa has not been well documented, and there have been few studies of the biology and ecology of dominant or important species, the use of ants as indicators is severely hampered by this lack of knowledge. In a country impacted heavily by various kinds of anthropogenic disturbance (e.g. land clearing, exotic livestock grazing and locust control operations), it is vital that the limited knowledge base concerning the composition and habitat requirements of the endemic ant fauna be improved so they can be used more effectively as indicators of ecosystem health and disturbance.
The herbivorous arthropods associated with the invasive alien plant, Arundo donax, and the native analogous plant, Phragmites australis, in the Free State Province, South Africa : short communicationsSource: African Entomology 22, pp 454 –459 (2014)More Less
The Enemy Release Hypothesis (ERH) predicts that when plant species are introduced outside their native range there is a release from natural enemies resulting in the plants becoming problematic invasive alien species (Lake & Leishman 2004; Puliafico et al. 2008). The release from natural enemies may benefit alien plants more than simply reducing herbivory because, according to the Evolution of Increased Competitive Ability (EICA) hypothesis, without pressure from herbivores more resources that were previously allocated to defence can be allocated to reproduction (Blossey & Notzold 1995). Alien invasive plants are therefore expected to have simpler herbivore communities with fewer specialist herbivores (Frenzel & Brandl 2003; Heleno et al. 2008; Heger & Jeschke 2014).
Author J.M. MidgleySource: African Entomology 22 (2014)More Less
Whitney Cranshaw has a reputation for public outreach related to entomology, and so it is not surprising that he has co-authored a text book such as this one. The book is designed as an introductory text, and the detail provided is appropriate for this task. It is aimed at students who are not necessarily intending to major in entomology, though entomology majors will also benefit from this book as an introduction. The focus is on diversity, as many texts of this type are, but does also cover some morphology and physiology.