Abstract Many bacteria strains are now successfully used for plant-growth promotion (PGPR) and as biocontrol agents (BCA) against plant diseases. Mechanisms behind their action involve production of enzymes and antibiotics, which in high concentrations could also affect non-target organisms hence the biodiversity and processes in the soil. Despite these potential negative side effects, there is little research done on the subject to confirm whether they are significant. In three laboratory e...
Abstract Bacterial wilt disease caused by Ralstonia solanacearum is one of the major diseases affecting solanum species, including cultivated African nightshade (Solanum nigrum L). The bacterial wilt (BW) management in the african nightshade vegetable presents a great challenge to production due to high survival rate of the pathogen in soil. Use of chemical application to control the disease is not eco-friendly. There is increasing demand for the crop as a vegetable and medicinal plant. Farm...
Abstract In insect species characterized by inbreeding, limited dispersal, and a metapopulation structure, high genetic differentiation and reduced genetic diversity within local populations are expected. Using the model system Lysiphlebus hirticornis Mackauer, a specialist parasitoid of the tansy aphid, Metopeurum fuscoviride Stroyan (Hemiptera: Aphididae), we examined within-site temporal population dynamics and genetics, including molecular variation at the tansy plant level. Aphid-parasi...
Abstract: Protected savannas are essential reserves for biological diversity, including endangered arthropod species, however, extreme grazing by mammals has cascading impacts on the communities and disrupts the functioning of these ecosystems globally. The current study assessed the abundance, species richness and composition of arthropods at the long-term grazing exclosures of Kruger National Park, South Africa. Pitfall traps and active searches were used to sample arthropods at the ungraz...
Abstract: Parasitic plants, through a range of infestation strategies, can attack crop plants and thereby require management. Because such problems often occur in resource-poor farming systems, companion cropping to manage parasitic plants is an appropriate approach. Many examples of companion cropping for this purpose have been reported, but the use of cattle forage legumes in the genus Desmodium as intercrops has been shown to be particularly successful in controlling the parasitic witchwe...
Abstract: Anopheles gambiae Giles s.s. (Diptera: Culicidae) is known to feed on plant sugars, but this is the first experimental study to consider whether it discriminates between plant species. Thirteen perennial plant species were selected on the basis of their local availability within the vicinity of human dwellings and larval habitats of An . gambiae s.s. in western Kenya. Groups of 100 or 200 mosquitoes were released into cages either with a cutting of one plant type at a time (single-...
Abstract: Studies were conducted between May and June, 2006 to investigate the environmental factors affecting the distribution of An. arabiensis Patton and Culex quinquefasciatus Say in Mwea, Kenya. The sampling unit comprised all nonpaddy aquatic habitats and ten randomly selected paddies and canals located within a 200 m radius from the periphery of the study site. Thirteen physico-chemical variables were recorded for each sampling site in each sampling occasion and a sample of mosquito l...
Abstract: The root-burrowing nematode, Radopholus similis, is reputedly the most damaging nematode pest of banana and responsible for major production losses. In this study, the endophytic potential of 13 fungal isolates was assessed for the management of R. similis in East African Highland bananas (‘Ng’ombe’). All isolates successfully colonised tissue-cultured banana roots, with isolates from Trichoderma, Fusarium and Hypocrea producing the highest (⩾49.1%) and Beauveria isolates t...
Abstract: Optimization of plant regeneration protocol is a first critical step to facilitate techniques such as transgenesis, cisgenesis and genome editing. In this study, we assessed: i) influence of explant type on regeneration efficiency (RE); ii) RE of 33 sub-Saharan African sweetpotato cultivars; and iii) levels of endogenous zeatin riboside (ZR), indole-3-acetic acid (IAA) and their correlation to RE. Indirect organogenesis was conducted using a 2-step protocol: step-1, explants were c...
Abstract: Phlebotomine sand flies are vectors ofLeishmaniaparasites that causeleishmaniases. Both sexes of sand flies feed on plants primarily for sugars, althoughthe chemical cues that mediate attraction to host plants remain largely unknown.Previously, using coupled gas chromatography-mass spectrometry, the authors identifiedseveral volatile organic compounds (VOCs) common to preferred host plants forselected Afrotropical sand flies from the Fabaceae family. Of the identified volatiles,the...
Abstract: Background: Understanding the ecology and behaviour of disease vectors, including the olfactory cues used to orient and select hosts and egg-laying sites, are essential for the development of novel, insecticide-free control tools. Selected graminoid plants have been shown to release volatile chemicals attracting malaria vectors; however,whether the attraction is selective to individual plants or more general across genera and families is still unclear.Methods: To contribute to the ...
Abstract: The tomato leafminer, Tuta absoluta is a destructive invasive pest of cultivated tomato and other Solanaceae plants, with yield losses of 80-100%. Mirid predators are key natural enemies of T. absoluta, but they also feed on host plants in the absence of their prey. Management of T. absoluta is a challenge due to its high biotic potential, resistance to many insecticides and the absence of sufficiently adapted auxiliary fauna in its new dispersion zones. Olfaction plays an importan...
Abstract: The mechanism underlying the mediation of the behavior and fitness of non-vector herbivores by fungal pathogen-infected host plants is still unclear. In this study, we experimentally assessed the effects of tomato (Lycopersicon esculentum L.) plant infection status on non-vector herbivores using tomato powdery mildew disease fungus (Oidium lycopersici) and the greenhouse whitefly Trialeurodes vaporariorum as a model multitrophic plant-pathogen, non-vector herbivore interaction. In ...
Abstract: Temperature is an important factor determining the abundance, distribution and diversity of termite species. Thus, termites are affected by changing climate and have to adopt different means of surviving in order to avoid extinction. Using termite occurrence data, bioclimatic variables and vegetation cover, we modelled and predicted the current and future habitat suitability for mound-building termites in Nigeria. Of the 19 bioclimatic variables and the vegetation index (NDVI) test...
Abstract: The perception of airborne chemical signals by plants can trigger reconfigurations of their metabolism that alter their bioticinteractions. While plant-to-plant chemical communication has primarily been studied in the context of eliciting defenses toherbivores and pathogens, recent work suggests that it can also affect plants’ interactions with their rhizosphere microbiomes. Inthis perspective, we discuss the potential for integrating the fields of plant-to-plant communication an...