Abstract: Captive multi-mammate mice, Mastomys natalensis, were paired and kept on one of three treatment diets (low, medium and high protein) in order to assess differential maternal investment in the sexes, and sex-specific resource allocation of offspring. The influence of maternal dietary protein content on maternal reproductive performance, sex-specific body composition of pups and pup growth from birth to weaning was determined. Mothers on the high protein diet were larger than those o...
Abstract: The present study arrived at investigating the influence of supplementary food on a developing rodent community on the coastal dune forests north of Richards Bay, South Africa. Four sites were selected for the field experiment. Each of these study sites comprised a treatment and control grid. Sunflower seeds were provided on the treatment grids and the response thereof on rodent population and community variables were measured. Each of the grids were trapped on a monthly bases as t...
Abstract: Please read the abstract in the section 00front of this document
Abstract: Avermectins and milbemycins are commonly used in agro-ecosystems for the control of parasites in domestic livestock. As integral members of agro-ecosystems with importance in maintaining pasture health through dung burial behaviour, dung beetles are an excellent, non-target, bio-indicator taxon for examining potential detrimental effects of pesticide application. The current study uses the dung beetle species, Euoniticellus intermedius (Reiche), as a bio-indicator to test the relat...
Abstract: Four grids, each 3,42 ha (4 morgen) in size, were live trapped from April 1967 through May 1969 in two soil and vegetation types (black turf~ Acacia nigrescens community, and brown reddish soil: Acacia tortilis community) at Pongola, northern Zululand, to determine the effect of dieldrin coverspraying, at a dosage of 87,4 g/hectare (2,64 oz/morgen), on rodents. Low population numbers before and especially at the time of spraying made clear-cut conclusions impossible to reach. Roden...
Abstract: Gonipterus scutellatus species complex is a cryptic species that feeds on Eucalyptus leaves. Both the adult and larval stages cause high levels of defoliation. Gonipterus sp. n. 2 is the species present in South Africa and Anaphes nitens was released as a biological control agent. However, Gonipterus spp. populations have continued to cause economic damage and various countries continue to seek additional biological control agents. This dissertation focused on understanding how nat...
Abstract: Common bean is an essential crop for food security, nutrition, and country economy mainly for Sub-Saharan African’s smallholder farmers. However, the production and productivity of common bean is mainly constrained by post-harvest loss induced by Mexican bean beetle. Thus, the objectives of this study were to evaluate the effectiveness of Plant seed powders (neem, Hochst and wild marigold), leaf powders (sweet fennel and broad-leaved croton), plant essential oils (neem and Hochst...
Abstract: The fall armyworm (FAW) (Spodoptera frugiperda) is a devastating pest of maize which has recently invaded the African continent. Since its first reports in Africa in 2016, it has spread rapidly in Zambia and it is causing extensive damage to maize and other cereal crops. The efficacy of the integration of botanical pesticides with entomopathogenic fungi and synthetic pesticide, on FAW were tested under field conditions. The experiment was laid out in a randomized complete block des...
Abstract: The study was conducted in Oromia Region, Eastern Hararghe zone,Grawa districtand in Haramaya University 2019/2020. The objectives were to assess beekeeping practices in Grawa district and the effect of different comb cuttingon the number and size of sealed queen cell cups in Haramaya University apiary to generate baseline information for further research and development. From Grawa district, six potential kebeleswere selected kebeles (two from three agro ecologies) and from those ...
Abstract: Lepidopteran stemborers are key destructive insect pests of cereal crops in sub-Saharan Africa with the indigenous noctuids Busseola fusca (Fuller) and Sesamia calamistis Hampson and the exotic crambid Chilo partellus Swinhoe accounting for ~5-75% of potential cereal crop yield losses. The main larval endoparasitoids comprising, indigenous Cotesia sesamiae and exotic Cotesia flavipes Cameron contribute to a significant extent in managing these economic herbivorous insect pests. How...
Abstract: Plastic adjustments of physiological tolerance to a particular stressor can result in fitness benefits for resistance that might manifest not only in that same environment, but might also be advantageous when faced with alternative environmental stressors, a phenomenon termed cross-tolerance. The nature and magnitude of cross-tolerance responses can provide important insights into the underlying genetic architecture, potential constraints on, or versatility of, an organism’s stre...
Abstract: Global insect pest invasions have dramatically increased over the past decades, posing significant biosecurity threats to natural and managed ecosystems. As such, the mechanisms of spread and rapid establishment of invasive species have been a key issue for agricultural stakeholders. Similarly, while availability of suitable plant hosts is key to establishment, the eco-physiological mechanisms facilitating invasion amongst most invasive species are unclear. The South American ...
Abstract: Pheromone trap catches were used to study the spatial distribution of Diamondback moth (DBM), Plutella xylostella L., at both single field and regional levels. At the field level, the DBM population tended to remain within the cabbage field. At the regional level, DBM captures were highly influenced by geographic location and cropping systems. In highland areas, daily maximum temperatures positively influenced the aggregation index, whereas in the lowland areas, rainfall had a nega...
Abstract: The reproductive compatibility between four different species/populations of the tephritid parasitoid Psyttalia (Walker) species from Kenya and individuals of the morphologically identical Psyttalia concolor (Sze´pligeti) (Hymenoptera: Braconidae) from a laboratory culture in Italy used in augmentative biological control of olive fly, Bactrocera oleae (Gmelin) (Diptera: Tephritidae) was assessed through cross mating tests using single-pair and group mating methods. Reciprocal cros...
Abstract: Plant and surrogate stems exhibiting specific combinations of physical cues were used to determine which plant-related stimuli influence the oviposition of Busseola fusca (Fuller) (Lepidoptera: Noctuidae). The number of eggs and egg batches laid per female increased with an increase in diameter of both natural and artificial stems. Direct observations of the oviposition behaviour (walking, antennating, and sweeping with the ovipositor) indicated that the female moths preferred ovip...