Abstract: The relationship between beetles and flowers is often mutually beneficial. Flowers provide not only edible rewards and favourable micro-environments, but may also be sites for mating and egg-laying activities. Even though beetles consume various parts of flowers, including pollen, and can sometimes cause considerable damage, they are in fact important pollinators of many flowers. Pollen was once considered indigestible but is actually a highly nutritious food source for many animal...
Abstract: Scarabaeus (Pachysoma) consists of 13 flightless dung beetle species endemic to the arid west coast of southern Africa. Scarabaeus (Pachysoma) are unique in their feeding and foraging habits, in that they randomly search for dry dung/detritus which, when found, is dragged forwards, and buried in a pre-constructed holding chamber, as opposed to the convention of rolling it backwards. This action is repeated to provision the chamber after which the nest is expanded to below the moist...
Abstract: Please read the abstract in the section 00front of this document
Abstract: Please read the abstract in the section, 00front, of this document
Abstract: Please read the abstract in the section front of this document
Abstract: Human appropriation of natural resources, and the consequent loss of habitats, means that ecological restoration may in the future become a vital conservation tool. For this to happen, we have to understand the processes and factors that govern community assembly, and their management. Here I analyze data on community structure (richness, evenness, diversity, composition) of assemblages (millipedes, spiders, dung beetles, plants, birds, rodents), and on soil chemical and physical p...
Abstract: Rastrococcus iceryoides Green (Hemiptera: Pseudococcidae), an alien invasive mealybug pest of Asian origin was first detected in Tanzania in 1989. This pest rapidly spread by the mid-1990s and was soon present in Coastal Kenya and Northern Malawi, where it has been regarded and remains a major pest of mango. Because of its novelty status, there was no information on its biology, ecology and its natural enemies that could aid development of management efforts. This study, therefore,...
Abstract: There are many examples of associations between insects and fungi. Where the fungi involved are pathogens, such associations may be of economic importance. Insects of no economic concern alone can also become important pests because of their association with fungal pathogens. Insects may assist in the spread of pathogens by carrying them on or in their bodies. Insects may also predispose plants to infection by creating wounds during feeding, oviposition or other behavioural activit...
Abstract: Please read the abstract in the section 00front of this document
Abstract: Please read the section 21chapter20, (Summary and conclusions), of this document
Abstract: Mealybugs (Hemiptera: Pseudococcidae) cause severe damage to many commercial crops, including grapevine. This is largely because of their ability to transmit various grapevine viral diseases, in particular grapevine leafroll-associated viruses (GLRaVs). Grapevine leafroll is one of the most wide-spread grapevine diseases worldwide. Managing the field-spread of grapevine leafroll disease requires, amongst others, stringent mealybug control. Mealybug monitoring and control methods re...
Abstract: Earthworms have an important role to play in turfgrass. They aerify and enrich the soil, enhance water infiltration and break down thatch. Turfgrass managers are advised to select pesticides non-hazardous to earthworms to maintain the long-term stability of a healthy turf An artificial soil test was used to assess the toxicity of five insecticides, used for turf grass pest management, on the Pheretima group (Megascolecidae). The recommended application rates of carbaryl, chlorpyrif...
Abstract: Morphological variation was examined in 58 species of Canthon and 18 species of other genera of the subtribe Canthonina (Anisocanthon, Canthonella, Cryptocanthon, Deltochilum, Hansreia, Holocanthon, Malagoniella, Melam canthon, Scybalocanthon, and Sylvicanthon). A total of 667 specimens was used for examination of morphological characters. Variation in head structures such as clypeus, eyes, labium, gula, and epipharynx is described. Thoracic structures examined include the pronotum...
Abstract: In South Africa the genus, Eucalyptus plays an important role as a major economic component in the forest and mining sector. Unfortunately, this genus has problems due to damage by pests. The Eucalyptus snout beetle, Gonipterus scutellatus, feeds and defoliates the leaves of eucalypts. Plants produce secondary metabolites, which protects them against defoliation by insects and herbivores. This study focuses on the variations of total soluble phenolic content of nine Eucalyptus spec...
Abstract: In South Africa, the genus Eucalyptus plays an important role as a plantation tree and hence forms a major economic component in the forest sector. An insect pest of these Eucalyptus species, Gonipterus scutellatus, causes periodic defoliation in the plantations. Plants have extraordinary array of chemicals (secondary metabolites), which defend them from herbivores. This study reports on the seasonal variation of the tannin concentration and carbohydrate content of the leaves of ni...