Abstract: The fruit fly species, Ceratitis rosa sensu stricto and Ceratitis quilicii, are sibling species restricted to the lowland and highland regions, respectively. Until recently, these sibling species were considered as allopatric populations of C. rosa with distinct bionomics. We used deep Next Generation Sequencing (NGS) technology on intact guts of individuals from the two sibling species to compare their transcriptional profiles and simultaneously understand gut microbiome and host ...
Abstract: Intra- and interspecific interactions within communities of species that utilize the same resources are characterized by competition or facilitation. The noctuid stemborers, Busseola fusca and Sesamia calamistis, and the crambid stemborer, Chilo partellus were the most important pests of maize in sub-Saharan Africa before the recent “invasion” of fall armyworm (FAW), Spodoptera frugiperda, which currently seriously limits maize yields in Africa. This new pest is interacting wit...
Abstract: Whitefly-transmitted cassava mosaic begomoviruses (CMBs; family Geminiviridae; genus Begomovirus) are viruses with bipartite genomes (components referred to as DNA-A and DNA-B) containing a conserved (between the two components) non-coding sequence known as the common region (CR) required for DNA replication and transcription (Fondong,2013). CMBs cause cassava mosaic disease (CMD), a major limitation to cassava production in sub-Saharan Africa. In Kenya, CMD is associated with the ...
Abstract: The mealybug Phenacoccus solenopsis Tinsley (Sternorrhyncha: Pseudococcidae) is a highly polyphagous pest of fruits, vegetables, crops and ornamentals in Pakistan. Biological control approach by using Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae) has been developed recently to control this pest. However, the efficiency of this parasitoid is variable according to the locality and the plants on which P.solenopsis is feeding. In this context, this experiment investigated under f...
Abstract: Cultivation of drought-tolerant (DT) maize seed reduces drought risk in sub-Saharan Africa. Data from eastern Uganda reveal gender gaps in awareness and adoption of DT maize. Among surveyed male household heads, 67.6 percent had awareness of DT maize varieties and 29.2 percent grew them. Corresponding figures for female household heads were 43.3 percent (awareness) and 5.3 percent (adoption) and those for wives in spousal couple households were 51.0 percent and 11.1 percent. Propen...
Abstract: BACKGROUND: Tetranychus evansi (Te) is an exotic pest of solanaceous crops in Africa. The predatory mite Phytoseiulus longipes (Pl) and the fungus Metarhizium anisopliae (Ma) are potential biocontrol agents of Te. The present study investigated the efficacy of fungus-treated foam placed above or below the third Te-infested tomato leaf. The persistence of fungus-treated foam and the performance of Pl with and without fungus-treated foam were evaluated. RESULTS: The fungus-treated fo...
Abstract: Evaluation of two microbial agents, Trichoderma asperellum and Bacillus subtilis and fungicide Linkimil 72 WP against rice blast disease, Pyricularia oryzae were done in a laboratory and pot experiment. Dual inoculation of T. asperellum, B. subtilis and Linkimil 72 WP caused significant inhibition of radial growth of P. oryzae. Both T. asperellum and B. subtilis showed over 75% inhibition of radial growth (PIRG) compared to Linkimil 72 WP with PIRG range of 21-23 % and control with...
Abstract: Maize (Zea mays L.) production in Africa is constrained by several biotic and abiotic factors. The recent occurrence of fall armyworm (FAW), Spodoptera frugiperda (JE Smith) a new invasive pest in Africa, has escalated the problem. Push–pull technology (PPT), proven to be effective for stemborers (Chilo partellus Swinhoe and Busseola fusca Fuller) and the parasitic weed striga (Striga hermontica Delile) management in Africa has been shown to provide good control of FAW. This stud...
Abstract: The objective of this paper was to investigate farmers’ knowledge and management of rice blast disease in Tanzania. Farmers’ household survey was conducted in five districts namely Mvomero, Morogoro rural, Ulanga, Korogwe and Muheza in April and May 2017. Data were collected through face-to-face interviews using semi-structured questionnaire and observations made through transect walks across selected villages. Farmers observed symptoms of rice blast disease for the first time ...
Abstract: We estimate the impacts of a bundle of integrated pest management (IPM) practices on mango yield, mango net income, insecticide use, human health and the environment, using recent household survey data of mango growers in Kenya. We employ a multinomial endogenous switching treatment regression model with an ordered probit selection rule to establish counterfactual outcomes. Our results indicate that IPM-adopting farmers have higher mango yields and mango net income,and also use low...
Abstract: Fall armyworm, Spodoptera frugiperda (J E Smith), an economically important pest native to tropical and subtropical America has recently invaded Africa, causing substantial damage to maize and other crops. We evaluated functionality of a companion cropping system, ‘climate-adapted push-pull’, developed for control of cereal stemborers in drier agro-ecologies, as an added tool for the management of fall armyworm. The technology comprises intercropping maize with drought-tolerant...
Abstract: This paper documents a positive relationship between maize productivity in western Kenya and women’s empowerment in agriculture, measured using indicators derived from the abbreviated version of the Women’s Empowerment in Agriculture Index. Applying a cross-sectional instrumental-variable regression method to a data set of 707 maize farm households from western Kenya, we find that women’s empowerment in agriculture significantly increases maize productivity. Although all indi...
Abstract: Sub-Saharan Africa (SSA) is a region beset with challenges, not least its ability to feed itself. Low agricultural productivity, exploding populations, and escalating urbanization have led to declining per capita food availability. In order to reverse this trend, crop production systems must intensify, which brings with it an elevated threat from pests and diseases, including plant-parasitic nematodes. A holistic systems approach to pest management recognizes disciplinary integrati...
Abstract: In this study, we tested whether GLS field symptoms on maize can be detected using hyperspectral data re-sampled to WorldView-2, Quickbird, RapidEye and Sentinel-2 resolutions. To achieve this objective, Random Forest algorithm was used to classify the 2013 re-sampled spectra to represent the three identified disease severity categories. Results showed that Sentinel-2, with 13 spectral bands, achieved the highest overall accuracy and kappa value of 84% and 0.76, respectively, while...
Abstract: The aim of this study was to determine the effect of sealing methods, grain volume and lighting candle in metal silo for the control of Prostephanus truncatus in stored maize. Metal silos with 100 kilograms holding capacity were loaded with 90 kilograms of grain, in-let and out-let were covered with lids and sealed either with rubber band, grease, rubber band combined with grease and lid without sealing (control). The control suffered highest grain damage of 6.6% and weight loss of...