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This paper describes the findings of a study that used a multi‐market model to assess the potential impact of improved maize technologies on the welfare of various types of rural and urban households in Kenya. The modelling results indicate that technologies developed for high potential regions are likely to have more profound aggregate impacts on maize production and lead to greater reductions in import demand (if prices are controlled) or maize prices (if maize prices are flexible). Technology adoption in high potential regions is likely to have substantially greater positive impacts on aggregate real incomes, but inferior income distributional outcomes compared to technology adoption in marginal regions.

Plant viral diseases are one of the major limitations in legume production within sub Saharan Africa (SSA), as they account for up to 100 % in production losses within smallholder farms. In this study, field surveys were conducted in the western highlands of Kenya with viral symptomatic leaf samples collected. Subsequently, next-generation sequencing was carried out. The main aim was to gain insights into the selection pressure and evolutionary relationships of Bean common mosaic necrosis virus (BCMNV) and Cowpea aphid-borne mosaic virus (CABMV), within symptomatic common beans and cowpeas. Eleven near complete genomes of BCMNV and two for CABMV sequences were obtained from SSA. Bayesian phylogenomic analysis and tests for differential selection pressure within sites and across tree branches of the viral genomes was carried out. Three distinct well-supported clades were identified across the whole genome tree, and were in agreement with individual gene trees. Selection pressure analysis within sites and across phylogenetic branches suggested both viruses were evolving independently, but under strong purifying selection, with a slow evolutionary rate. These findings provide valuable insights on the evolution of BCMNV and CABMV genomes and their relationship to other viral genomes globally. These results will contribute greatly to the knowledge gap surrounding the phylogenomic relationship of these viruses, particularly for CABMV, for which there are few genome sequences available, and support the current breeding efforts towards resistance for BCMNV and CABMV.

Sixteen progeny lines of common beans obtained from single crosses made between two parents, GLP2 and KAT B1, were grown in randomized complete block design in a rainout shelter at the Agricultural and Mechanization Research Institute, Machakos, Kenya. e experiment was conducted to study inheritance of traits associated with drought stress adaptation and to establish if significant variation for those traits was existing in order to carry out selection for drought tolerance. e calculated mean values were used to estimate heritability, genetic advance, and correlation study for each trait. Water stress had a significant (p ≤ 0.01) effect on the number of pods per plant, grains per plant, 100-seed weight, and yield per plant. e highest values for genotypic coefficient of variation (36.11%) and phenotypic coefficient of variation (36.70%) were recorded for pods plant -1 under stress condition. Highest broad-sense heritability estimates (96.54%, 94.97%, and 93.16%) coupled with high genetic advance as percent of the mean (22.32%, 34.97%, and 26.32%) were obtained for the number of pods plant − 1 , days to maturity, and yield plant − 1 , respectively, showing that selection of these traits together could lead to yield improvement under stressed conditions. Harvest index showed a significant and positive relationship with biomass aboveground (r � 0.86) and the number of pods plant − 1 (r � 0.86) indicating the possibility of identifying high performing lines of common beans for drought stress environment for further studies on these traits.

This paper describes the findings of a study that used a multi-market model to assess the potential impact of improved maize technologies on the welfare of various types of rural and urban households in Kenya. The modelling results indicate that technologies developed for high potential regions are likely to have more profound aggregate impacts on maize production and lead to greater reductions in import demand (if prices are controlled) or maize prices (if maize prices are flexible). Technology adoption in high potential regions is likely to have substantially greater positive impacts on aggregate real incomes, but inferior income distributional outcomes compared to technology adoption in marginal regions.

The outbreak of coronavirus was expected to adversely affect African countries more than any other region in the world. This assertion was based on the existing conditions in sub-Saharan Africa that exposed the region to the dire consequences of the pandemic. Previously existing underlying conditions that affected the food system include a high dependence on trade for inputs supply, the adverse effects of climate change, crop pests and diseases, poverty, low input use, weak institutions and ineffective poli¬cies, and insecurity and conflicts. We collected data from farmers, aggregators, bean research coordina¬tors, and urban and peri-urban consumers in five Eastern African countries in order to describe the immediate impacts of the pandemic on the bean value chain. Access to seed and labor appear to be the most critical impacts of the pandemic on bean production. There are observable differences in patterns and frequency of bean consumption in these regions, suggesting that the effect of the pandemic depends on the level of implementation of containment measures and pre–COVID-19 underlying conditions that affect the food systems. In the mid to long-term, the pandemic may disrupt food systems, resulting in hunger, malnutrition, and food insecurity. Thus, governments should support farmers and businesses in becoming resilient to exogenous shocks through increased efficiency in supply chains, capacity building, and the adoption of modern digital technology.

Plant viral diseases are one of the major limitations in legume production within sub-Saharan Africa (SSA), as they account for up to 100% in production losses within smallholder farms. In this study, field surveys were conducted in the western highlands of Kenya with viral symptomatic leaf samples collected. Subsequently, next-generation sequencing was carried out to gain insights into the molecular evolution and evolutionary relationships of Bean common mosaic necrosis virus (BCMNV) and Cowpea aphid-borne mosaic virus (CABMV) present within symptomatic common bean and cowpea. Eleven near-complete genomes of BCMNV and two for CABMV were obtained from western Kenya. Bayesian phylogenomic analysis and tests for differential selection pressure within sites and across tree branches of the viral genomes were carried out. Three well–supported clades in BCMNV and one supported clade for CABMNV were resolved and in agreement with individual gene trees. Selection pressure analysis within sites and across phylogenetic branches suggested both viruses were evolving independently, but under strong purifying selection, with a slow evolutionary rate. These findings provide valuable insights on the evolution of BCMNV and CABMV genomes and their relationship to other viral genomes globally. The results will contribute greatly to the knowledge gap involving the phylogenomic relationship of these viruses, particularly for CABMV, for which there are few genome sequences available, and inform the current breeding efforts towards resistance for BCMNV and CABMV.

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