Browsing by Author "Quee, Dan David"

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    Differential responses of two cowpea (Virgina unguiculata L.Walp.) genotypes to pre-emergence herbicides in the savannah woodland and rainforest agroclimatic regions of Sierra Leone
    (GSC Online Press, 2021-04-30) Quee, Dan David
    Field trials were conducted in savannah woodland (Njala) and rainforest (Serabu) agroclimatic regions of Sierra Leone during 2016 second cropping season to assess different preemergence herbicides techniques that is efficient, cost effective and environmentally safe in cowpea production. The experiment consisted of 20 treatments which included 2 cowpea genotypes (slipea 4 and slipea 5) and 10 different weed control techniques viz: butachlor 50% emulsifiable concentrate (EC), double force®, power force® applied as preemergence herbicides at 2, 4 and 6 L ha-1, respectively and weedy check. The treatments were laid out in a strip-plot design arranged in a factorial system with three replications. The results of this study revealed that the application of power force® at 6 L ha-1 recorded the highest phytotoxic effect, lowest weed dry weight, number of pods per plant and grain yield, highest total variable cost, lowest gross and net returns. Furthermore, butachlor 50% EC at 2 L ha-1 closely followed by double force® at 6 L ha-1 resulted in maximum grain yield, gross and net returns compared to the rest of the other weed control techniques. Thus, it is concluded that butachlor 50% EC at 2 L ha-1 was more economical, profitable and beneficial than other control treatments in the production of cowpea genotypes in the savannah woodland and rainforest agroclimatic regions of Sierra Leone. Conclusively, the relationship between phytotoxicity and grain yield indicates that the higher the grain yield the lower the phytotoxic effects of the chemicals.
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    Orange-fleshed potato cultivars’ responsiveness to herbicides and weed species interruption in Njala, Moyamba District, Southern Sierra Leone.
    (GSC Online Press, 2023-09-30) Quee, Dan David
    The 2019 and 2020 field experiments were established to evaluate pre-emergence herbicides and weed interruption on orange-fleshed potato cultivars’ productivity. The experiment was executed at the Crop Protection Department trial site, Njala University Campus using a strip-plot design in three replications. Results indicated that Button (Diodia scandens) and Rushfoil (Croton hirtus) broadleaved weed species arose as the utmost predominant weed types that showed 58.52% and 25.68% relative density, respectively. Notwithstanding, Mathuthu orange-fleshed cultivar exhibited maximum weed competitive ability (5.14). The application of Prometraine (5 L ha-1) and hand weeding at 4 weeks after planting, revealed maximum herbicide efficiency index (20.65), yield (7.04 t ha-1), net field benefit (SLL 2,564.64), total variable cost (SLL 2,300.00) as well as profitability (113.48%). Therefore, application of Prometraine (5 L ha-1) and supplementary hand weeding at 4 weeks after planting may be acknowledged to farmers as an efficient and cost-effective weed management strategy in orange-fleshed potato cultivars’ productivity.