There is little information on farmers’ knowledge about cassava (Manihot esculenta Crantz) brown streak disease (CBSD), despite extensive studies on incidences and severities. The objective of this study was to assess farmers’ knowledge of CBSD diagnosis and management. The study was conducted in three districts of Malawi by administering semi-structured interviews in combination with disease incidence and severity surveys. Farmers’ knowledge of disease diagnosis and management was associated with CBSD incidence and severity. High levels of knowledge about CBSD were observed in areas with high disease incidence. Only 10.1% of the farmers were capable of identifying the foliar symptoms of the disease. On average, 75.0% and 71.7% of the farms had leaf and storage root incidences, respectively. At harvest, 88.3% of the farmers’ fields exhibited storage root necrosis. CBSD leaf and storage root severities differed significantly (P < 0.001) from one district to the other and between varieties. Most farmers were found to lack a source of clean planting material. High needs for extension services on cassava cultivation methods and pest management were identified, but few farmers received such services. The lack of new improved varieties was reported as the most important constraint of cassava production, beyond CBSD. Education of farmers on the efficient management of this viral disease through selection of clean planting material should be provided. Additionally, the development of early root bulking cultivars as a long-term solution in avoiding CBSD impact should be supported.

Introduction: This study focuses on cowpea, a vital crop for smallholder farmers in sub-Saharan Africa, particularly in Malawi. The research aimed to understand the genetic diversity and population structure of cowpea and to perform genome-wide association studies (GWAS) to identify marker-trait associations (MTAs) for yield and related traits. These insights are intended to support varietal development and address agricultural challenges in Malawi.Methods: A total of 306 cowpea genotypes were characterized using single nucleotide polymorphism (SNP) markers and morphological traits. The study assessed the effects of genotype, location, and their interactions on morphological traits. The Fixed and Random Model Circulating Probability Unification (FarmCPU) algorithm was used to identify significant MTAs.Results: The morphological traits showed significant genotype, location, and interaction effects. Genotypes MWcp24, MWcp47, MWcp2232, and TVu-3524 yielded the highest values. Grain yield was positively correlated with peduncle length, seeds per pod, and pods per plant. Three distinct clusters were identified based on morphological traits. Genetic diversity analysis revealed an average minor allele frequency of 0.31, observed heterozygosity of 0.06, and gene diversity of 0.33. The average inbreeding coefficient was 0.82, indicating a high level of inbreeding. Most of the genetic variation (73.1%) was found among genotypes within populations. Nine groups and ancestral populations were identified, which did not entirely overlap with geographic origins. Sixteen significant MTAs were linked to six morphological traits.Discussion: The validation of these identified MTAs, along with the observed genetic diversity, offers valuable opportunities for cowpea improvement through marker-assisted selection, to addresses the challenges faced by Malawian farmers. The identification of thirty cowpea lines as key founder lines for breeding programs in Malawi, Mozambique, and Tanzania is a significant outcome. These efforts aim to develop more productive cowpea lines for the region, enhancing food security and agricultural sustainability.

Introduction: Cowpea is an important food and nutrition security crop in Malawi, Mozambique and Tanzania and it is mainly produced by women farmers mainly on a subsistence scale. The majority of these farmers use local varieties despite the availability of improved varieties in the region. Low acceptability and adoption of improved varieties have also hampered cowpea breeding efforts. The low adoption, especially among women farmers, has been attributed to the failure by breeding programs to involve farmers in the process of designing and developing improved varieties with a view to meeting their priorities and preferences. Despite women constituting the majority of cowpea farmers in these countries, no comprehensive gender analysis on cowpea value chain had been instituted to understand the traits that are gender and youth responsive and how to incorporate them in the product profiling so that the developed varieties benefit men, women and youth. The main objective of the gender study was, therefore, to identify preferred traits by different gender groups within the whole cowpea value chain to inform cowpea breeding programs in the three countries.Methods: The study employed quantitative and qualitative methods to elucidate preferences, including value chain mapping, a quantitative survey of farmers, focus group discussions and key informant interviews targeting farmers/consumers, traders, policymakers and processors.Results and discussion: Results showed that the top-ranking traits in order of importance across the countries and gender were; (1) high grain yield, (2) good grain taste, (3) early maturity time, (4) large grain size, (5) good leaf taste and (6) short cooking time. It was further noted that different gender groups preferred almost similar traits though minor variations were noted in terms of prioritization of these traits. These results have had two major influences on our cowpea breeding program: firstly, the breeding program changed the way it prioritizes traits to include ones that reflect the needs of men, women and the youth in the cowpea value chain. Secondly, our breeding objectives are closely aligned to gender differences in the target population of farmers and other users, by incorporating key priority traits that address the needs of both men and women, including the youth. That is to say, product targets and specific product profiles are more gender sensitive. Since the breeding work is ongoing, the expectation is that the development of improved varieties resulting from this gender sensitive process will translate into higher adoption levels of these varieties (compared with previous releases), which might have ripple effects on food, nutrition and income security in the region.

The need to develop new improved varieties resistant to cassava green mite (CGM) and cassava mealy bug (CMB) as well as high yielding varieties requires knowledge on the mode of gene action controlling the expression of resistant traits to these pests. Therefore, a study was carried out to determine combining abilities and mode of gene action for resistance to CGM and CMB by crossing cassava genotypes in a 7 × 7 diallel mating design. The F1 progenies were evaluated in a seedling trial laid in randomised complete block design (RCBD) with two replicates. Results indicated highly significant (P<0.001) general combining ability (GCA) and specific combining ability (SCA) mean squares for CGM, CMB, average root number per plant and fresh root weight (kg per plant) which signified preponderance of significant variability existing in breeding material attributable to additive and non-additive gene effects. GCA variances for all the traits studied were lower than SCA variances which suggested that non-additive gene action was more important than additive gene action in influencing the traits. Mulola was the overall best general combiner for all the traits, followed by TMS4 (2)1425 and 01/1316. The best ranking hybrids were Mulola × 01/1313, Silira × TMS4(2)1425, Depwete × Silira, Mulola × Silira, Depwete × Maunjiri and 01/1316 × TMS4(2)1425. Overall, the results suggested that when designing breeding programs breeders should exploit both additive and non additive types of gene action. Key words: Cassava green mite, cassava mealy bug, general combining ability, gene action, specific combining ability.

Grain quality, cooking quality, and nutritional quality traits are some of the major attributes that enhance the uptake and utilization of improved cowpea varieties. Therefore, there is a need for a better understanding of the genetic variation and inter-relationships among these quality traits in cowpeas to integrate them into cowpea breeding programs. This study was conducted to determine genetic variability among 306 cowpea genotypes for grain quality, cooking quality, and nutritional quality traits and to understand the interrelationships among these traits for exploitation in breeding programs. The results showed highly significant differences (p < 0.001) among genotypes for grain quality, cooking quality, and nutritional quality traits. The mean performance for these quality traits was also very variable. These results suggest that genetic variability exists in the cowpea genotypes studied, which can be exploited in breeding programs aimed at developing high-performing varieties for the said traits. Significant (p < 0.001) positive correlations were detected for protein content with iron and zinc. On the other hand, nutritional quality traits did not exhibit any association with grain quality or cooking quality traits. Cooking quality traits were also shown to be significantly and positively correlated with grain quality traits. This study has identified several genotypes with desirable quality-related traits that could be used in crossing programs to generate improved varieties with consumer-preferred traits to improve the food, income, and nutritional status of many smallholder farmers that largely depend on cowpeas.