A field experiment was conducted to evaluate efficacy of pre-emergence herbicides against major weeds in maize at Bako during the main rainy season of 2016/17. The trial was laid out in randomized complete block design (RCBD) with three replication, and consisted of five treatments including pre-emergence application of Lunar 537.5 SE at 3L/ha, Venus 500 SC at 6L/ha and Prima gram dual Gold 660sc at 3 L/ha, and two times hand weeding at 25 and 40 DAS and weedy check for comparison. Application treatments boosted maize grain yield over weedy check plots there by reducing weed infestation. Analysis of variance showed statistically significance difference (P < 0.01) for total weed density (m -2 ) and dry weight (gm.-2 ). Significantly the minimum density (8.5 m -2 ) was observed in plots treated two times hand weeding which was statistically similar with evaluated herbicides. In contrary, the highest (39.1 m -2 ) was observed in weedy check plots. All the herbicide treatments provided significant control of weeds causing significant reduction in density of target weed flora and also significantly improved the grain yield in comparison with the weedy check. However, no crop injury was observed in any of the herbicide treatments. The maximum grain yield (57.57 qt ha -1 ) was obtained from Lunar 537.5 SE at 3L/ha followed by two times hand weeding (57.08 qt ha ) was from weedy check plots. In general application preemergence herbicides effectively control weeds in maize and reduce yield losses. Thus, the newly tested pre-emergence herbicides (Lunar 537.5 SE at 3L/ha and Venus 500 SC at 6L/ha) alone could be option to major weeds and increase maize grain yield.

The fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) is among the invasive insect pests that damages maize and sorghum, the high-priority crops in newly colonized agro-ecologies, including African contexts. Owing to the increasing infestation of the pest and the limitations of current conventional methods for its management, there is a call for discovering advanced pest management approaches. RNA interference (RNAi) is an emerging molecular tool showing flexible potential for the management of S. frugiperda. We conducted a search of the recent application of RNAi literature using Google Scholar and Mendeley to find advanced papers on S. frugiperda management using RNAi molecular tools that led to growth inhibition, developmental aberrations, reduced fecundity, and mortality, mainly by disruption of normal biological processes of the pest. Although efforts have been made to accelerate the utility of RNAi, many factors limit the efficiency of RNAi to achieve successful control over S. frugiperda. Owing to RNAi’s potential bioactivity and economic and ecological acceptability, continued research efforts should focus on improving its broad applicability, including field conditions. Screening and identification of key target genes should be a priority task to achieve effective and sustainable management of this insect via RNAi. In addition, a clear understanding of the present status of RNAi utilization in S. frugiperda management is of paramount importance to improve its efficiency. Therefore, in this review, we highlight the biology of S. frugiperda and the RNAi mechanism as a foundation for the molecular management of the pest. Then, we discuss the current knowledge of the RNAi approach in S. frugiperda management and the factors affecting the efficiency of RNAi application. Finally, the prospects for RNAi-based insect pest management are highlighted for future research to achieve effective management of S. frugiperda.

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Two separate experiments were done for seedling and adult resistance in rice varieties against blast. Each experiment consists of 20 varieties and is evaluated under artificial inoculation with blast. The result of the study confirmed that NERICA varieties have shown low disease infection at the seedling stage whereas the varieties Chewaka and Edget have shown adult plant resistance. Severe yield reduction and highly diseased grain were obtained from Superica-1, which is highly susceptible at adult plant stage. In contrast, the maximum grain yield was obtained from the Chewaka and Edget varieties, these having a high level of adult resistance. Therefore, Chewaka and Edget are promising candidates for utilization in yield and blast resistance in rice improvement.