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Mount Darwin, Zimbabwe

Tibugari H.,Womens University in Africa | Jowah P.,University of Zimbabwe
Archives of Phytopathology and Plant Protection | Year: 2014

The African bollworm, Helicoverpa armigera (Hübner), and the cotton red spider mite, Tetranychus spp., are important pests of cotton in Zimbabwe. A study to assess H. armigera resistance to fenvalerate 20 EC (Cyano (3-phenoxyphenyl) methyl 4-chloro-α-(1-methylethyl)benzene acetate) and Tetranychus spp. resistance to amitraz 20 EC (n'-(2,4-dimethylphenyl)-n-[[(2,4-dimethylphenyl)imino]methyl]-n-) was conducted at the Cotton Research Institute (CRI) during the 2005/06 cotton-growing season. Field populations of H. armigera and Tetranychus spp. were collected from some of Zimbabwe's major cotton-growing areas of Sanyati, Umguza, Chisumbanje, Chinhoyi and the CRI in Kadoma and exposed to bioassays. The African bollworm leaf disc technique and the red spider mite attached leaf-dipping technique were used to assess responses of the African bollworm and red spider mite to the pesticides. Susceptible laboratory populations served as the standard populations and their responses were compared with those of the field populations. The graphical method and MSTAT-C probit analysis computer program were used to calculate LC50 values. Although the CRI field population, used as a reference population for the registration of H. armigera insecticides, had the highest LC50 value (graphical = 0.000100000; MSTAT-C = 0.000088195) compared with all the other field populations, overall log-dose probit bioassays on all field-collected strains of the bollworm showed no resistance to the pyrethroid (RFs = 0.04-0.54-fold). Tetranychus spp. showed very low levels of resistance (RFs = 1.26-2.00-fold). Continuous monitoring of major cotton pests, especially H. armigera and Tetranychus spp., from all cotton districts of Zimbabwe is vital for early detection of resistance development. © 2013 Taylor & Francis. Source

Mudita I.I.,Mulungushi University | Chipfiko T.,Womens University in Africa | Mapfumo P.,University of Zimbabwe | Tigere T.A.,University of South Africa
Journal of Agronomy | Year: 2014

Improvement of yield and quality of green mealies is paramount in green mealies production to guarantee high income for farmers and nourishment for consumers. A study was conducted to determine the effects of rate and time of application of multi-nutrient foliar fertilizer (OmniBoost) on cob length, kernel weight and crude protein content of green mealies in order to enhance income and nourishment from horticultural products. Evaluation was done on potential role of multi-nutrient foliar fertilizers on yield and nutritional quality of green mealies. OmniBoost was applied as a supplementary fertilizer at 4, 6 and 10 Weeks After Crop Emergence (WACE) using 0, 2, 4, 6 and 8 kg ha-1. Time of application had no significant effect on cob length, kernel weight and crude protein content. Rate of application had a significant effect (p<0.05) with 4 and 6 kg ha-1 giving the highest values for all attributes considered. Timexrate of application interaction was not significant (p>0.05). The optimum rate of application was established to be 4 kg ha-1. Increment of 2 kg ha-1 and doubling this rate resulted in no significant increase in attributes considered and it is not economic. Farmers may not apply beyond 4 kg ha-1 Om niB oost under similar crop production conditions in order to optimise yield, quality and income. Application of multi-nutrient foliar fertilizer may therefore be a practical consideration to enhance yield, quality and income from horticultural products. © 2014 Asian Network for Scientific Information. Source

Tibugari H.,Womens University in Africa | Mandumbu R.,Bindura University of Science Education | Jowah P.,University of Zimbabwe | Karavina C.,Bindura University of Science Education
Archives of Phytopathology and Plant Protection | Year: 2012

Cotton is an important cash crop and a means of survival for Zimbabwe's smallholder farmers who are located in the semi-arid areas. However, it is plagued by a wide variety of pests. The cotton industry in Zimbabwe came up with sustainable pest management strategies which include within the season rotation of bollworm pesticides, a closed season and acaricide rotation scheme. The land reform programme brought new players in the cotton industry and it was critical to determine their knowledge on the pest management strategies. A survey was conducted to determine farmer knowledge, practice and perception on the resistance management strategy. Responses indicated that both communal and new farmers based their spray on egg counts. Communal farmers knew when to use pyrethroids compared to new farmers. Farmers observed the acaricide rotation scheme although they use some non acaricide pesticides. More than half of the new farmers could not say which acaricides were in the acaricide scheme. The majority of the farmers reported that they adhered to the closed season although field observation revealed otherwise. A significantly higher number of new farmers knew when to slash cotton compared to communal farmers. Knowledge of acaricides was not common among farmers. Use of pyrethroids was not limited to 1 February onwards as stipulated in the cotton pest resistance management strategy. The results suggest the need for training among the cotton farmers especially the new farmers or refresher courses among the communal farmers. © 2012 Copyright Taylor and Francis Group, LLC. Source

Tibugari H.,Womens University in Africa | Jowah P.,University of Zimbabwe | Mandumbu R.,Bindura University of Science Education | Karavina C.,Bindura University of Science Education
Archives of Phytopathology and Plant Protection | Year: 2012

The diamondback moth (DBM), Plutella xylostella (L.) is a destructive pest of brassicas globally. Control of the pest is dominated by insecticides. Studies have shown that in some African countries, there is a great reliance on broad spectrum insecticides such as pyrethroids, organophosphates and carbamates, that are applied weekly or twice per week. Use of unregistered insecticides has also been reported. The quality of insecticide application has also been reported to be poor or ineffective. It is therefore not surprising that DBM is fast developing resistance to the major insecticides used against it. Adopting an integrated pest management strategy may be a good arsenal to use against the pest. © 2012 Copyright Taylor and Francis Group, LLC. Source

Chibanda D.,University of Zimbabwe | Verhey R.,University of Zimbabwe | Gibson L.J.,London School of Hygiene and Tropical Medicine | Munetsi E.,University of Zimbabwe | And 6 more authors.
Journal of Affective Disorders | Year: 2016

Background In low income countries in Sub-Saharan Africa there are few validated tools to screen for common disabling mental disorders such as depression and general anxiety disorder (GAD). Objectives We validated three screening tools: the Shona Symptom Questionnaire for common mental disorders (SSQ-14), the Patient Health Questionnaire for depression (PHQ-9), and the Generalized Anxiety Disorder questionnaire (GAD-7). The study participants were attendees at a primary health care clinic in Harare, Zimbabwe. Methods Consecutive adults aged 18 and above attending the clinic were enrolled over a two-week period in September 2013. Trained research assistants administered the screening tools to eligible participants after obtaining written consent. Participants were then interviewed by one of four psychiatrists using the Structured Clinical Interview of the DSM-IV (SCID). Performance characteristics were calculated for each tool, against the SCID as the gold standard. Results A total of 264 participants were enrolled, of whom 52 (20%) met the SCID criteria for depression alone, 97 (37%) for mixed depression and anxiety and 9 (3%) for anxiety alone. Of the 237 where HIV status was known, 165 (70%) were HIV positive. With the optimal cutoff of ≥9, the sensitivity and specificity for the SSQ-14 against a diagnosis of either depression and/or general anxiety were 84% (95%CI:78–89%) and 73% (95%CI:63–81%) respectively. Internal reliability was high (Cronbach α=0.74). The optimal cutoff for PHQ-9 was ≥11, which provided a sensitivity of 85% (95%CI:78-90%) and specificity of 69% (95%CI:59–77%) against a SCID diagnosis of depression (Cronbach α=0.86). The GAD-7 (optimal cutoff ≥10) had sensitivity and specificity of 89% (95%CI:81–94%) and 73% (95%CI:65–80%) respectively against a SCID diagnosis of GAD (Cronbach α=0.87). Conclusion Screening tools for depression and GAD had good performance characteristics in a primary health care population in Zimbabwe with a high prevalence of HIV. These can be used for research and also in clinical care to screen patients who may benefit from treatment © 2016 Elsevier B.V. Source

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