Abstract: Despite the vast research on trichome-based resistance as well as plant chemical factors in plant-herbivore interactions in Solanaceous plants, little or no information is available on the association between Tetranychus evansi Baker and Pritchard and these mechanisms in African nightshades. The current study which was carried out from December, 2006 to March, 2009 focused on five African nightshade species viz. Solanum sarrachoides Sendter, S. villosum Mill, S. tarderemotum Bitter...
Abstract: The research described in this thesis focused on the characterization of some of the factors that influence disease assessment, development and expression of resistance in wheat cultivars to septoria tritici blotch. Earliness appeared to have a strong effect and tallness a small effect on disease severity (DS). A regression equation derived was used to correct the DS in the entries. Another method that gave good disease assessment was to group the cultivars according to their earli...
Abstract: Cereals particularly maize, are the most essential food and cash crops for majority of smallholder households in Sub-Saharan Africa (SSA). In maize production, small-sized producers are confronted with different constraints including stemborers, Striga and degraded soil leading to poor crop yields. In response to these challenges, the International Centre of Insect Physiology and Ecology (icipe) and collaborators came up with a habitat management approach; the Push-pull Technology ...
Abstract: Antestia bug Antestiopsis thunbergii (Gmelin) is a key insect pest of Arabica coffee associated with high losses in terms of quality, yield and export market of produce from the African region. Although the pest prefer feeding on unripe (mature) green berries than other coffee berry maturity stages or coffee parts, the cues that influence their host choice are unknown. In addition, A. thunbergii is gregarious in the field and produces a strong distinct smell while disturbed, which ...
Abstract: Agriculture is a fundamental source of sustainable livelihoods in sub-Saharan Africa and millions of people in the region rely solely on small-scale farming for their food security. However, the impacts of invasive alien species (IAS) on crop production are serious, and there is no sign of this abating. Among the recent IAS that have invaded Africa in the last decade, the South American tomato pinworm Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) has been one of the most damag...
Abstract: This study quantifies the effect of land cover change and seasonality on soil organic carbon and carbon dioxide emissivity. It takes to account the coupled inter-relationships with other ecological factors such as temperature and moisture. Next, the study assesses how topographic and ecological factors drive spatial soil nutrient stock variations and quantifies the observations required to discriminate stock detection in the mountain ecosystem. Thereafter, the study derives and eva...
Abstract: Studies were carried out to establish the role and significance of rice stem borers as pests of rice crop in irrigated low land rice ecosystems in Tanzania; and to evaluate the effectiveness of some management options against the pest. A survey by means of structured questionnaire was init ially used to assess the farmer’s perception on rice stem borers and their management practices in three wards of Kilombero district in Morogoro Region, namely, Mkula, Sanje and Signali. This w...
Abstract: The International Centre of Insect Physiology and Ecology (icipe), undertook a biological control (BC) programme for control of stemborers from 1993 to 2008, to reduce cereal yield losses due to stemborer attack in East and Southern Africa. The programme released four biological control agents—Cotesia flavipes, Cotesia sesamiae, Telenomus isis and Xanthopimpla stemmator—to control the economically important stemborer pests Busseola fusca, Chilo partellus and Sesamia calamistis....
Abstract: This study aimed to enhance effective rice blast disease management by the establishment of the current status of the disease, its effect on yield of selected upland rice genotypes and the use of environmentally friendly methods such as bio-agents and hot water seed treatment. Two surveys were conducted in 2017/2018 and 2018/2019 rice growing seasons to investigate farmers’ knowledge of rice blast disease and its management and to establish the incidence and severity of rice blas...
The experiment was conducted at the University of Port Harcourt Teaching and Research farm, Port Harcourt, Rivers State, Nigeria from April to August, 2019 on the effects of organic and inorganic fertilizers on the growth and yield of cucumber (Cucumis sativus L). The research was done in a randomized complete block design with four treatments and replicated four times. The treatments include control (no application), NPK 15:15:15, spent mushroom ...
Abstract: The study was carried out in two sites already with existing mulberry trees comprising three varieties, Kanva , Noi (Thailand), and Embu (local variety). The main objective of the study was to determine the effect of soil fertility and better mulberry varieties (grown locally) on cocoon and silk quality. The study compared the growth and yield performance of the three mulberry varieties being used by farrriers in silkworm rearing. It also involved comparisons of silk production usi...
Abstract: The objective of this study was to evaluate the efficacy of the pesticides commonly used by farmers in controlling the Tobacco spider mite Tetranychus evansi Baker & Pritchard. Laboratory and greenhouse experiments were carried out to determine the susceptibility of T. evansi to dicofol, bifenthrin, propargite, lambda-cyhalothrin, dimethoate and profenofos+cypermethrin using the manufacturer’s recommended rates. Ovicidal and adulticidal (contact and residual) assays were done in ...
Abstract: The Lepidopteran stemborer Chilo partellus is a key constraint to cereal production in most resource-poor farming systems as it causes damage to the crop, accruing up to 80%. When plants are damaged by herbivorous insects, they produce herbivore-induced plant volatiles (HIPVs) which can act as repellants for these insect pests and as attractants for organisms antagonistic to these pests (parasitic wasps and predators). Plants can also produce signals that warn other plants of impen...
Abstract: The Coffee Berry Borer, Hypothenemus hampei Ferrari is the most important pest of coffee worldwide. The predominant method for the pest control is application of broad spectrum pesticides, but they are often toxic to humans and pollute the environment, hence the need to search for safer alternatives. Spiroacetals represent a group of semiochemicals often used to manage various pests through manipulation of their behaviour. This study which was carried out between January 2013 and D...
Abstract: Lepidopteran stem borers are among field insect pests responsible for the low maize production in sub-Saharan Africa. In Kenya, Chilo partellus Swinhoe (Pyralidae), Busseola fusca Fuller (Noctuidae) and Sesamia calamistis Hampson (Noctuidae) constitute the major proportion of stemborer community. Concerted efforts to reduce stemborer populations in maize fields have been emphasized without a good understanding of potential losses associated with damage by respective stemborer speci...