Maize (Zea mays L.) is a food security crop in sub‐Saharan Africa (SSA). Incidence of northern corn leaf blight (NCLB), caused by Exserohilum turcicum, in lowlands of SSA during the past decade has caused 30–70% reduction in maize yield. This study (a) examined the combining abilities of extra‐early maize (EEM) inbreds and classified them into heterotic groups; (b) elucidated gene action controlling resistance to NCLB; (c) assessed grain yield (GYLD) and yield stability of EEM hybrids under NCLB infection; and (d) identified testers. One hundred and fifty EEM hybrids, obtained by crossing 15 inbreds each of white‐ and yellow‐endosperm maize using the North Carolina Design II, plus six checks, were evaluated in nine environments, six of which were inoculated with an isolate of E. turcicum and three of which were non‐inoculated in 2018 and 2019. The white and yellow inbreds were placed in three heterotic groups using the heterotic grouping based on general combining ability (GCA) of multiple traits and stability of GYLD using the genotype plus genotype × environment (GGE) biplot analysis. The GCA, specific combining ability (SCA) and genotype × environment (G×E) interactions were significant for GYLD, disease severity, and other measured traits. The GCA effects were more important than the SCA effects for GYLD and NCLB severity scores across environments, implying that recurrent selection could facilitate improvement for GYLD and NCLB resistance. Three inbred testers and four single‐cross testers were identified for developing high‐yielding NCLB‐resistant hybrids. Four white and five yellow single‐cross hybrids were identified for on‐farm testing and possible commercialization.

Various quality grades of high-quality cassava flour (HQCF) are found in markets due to the rapid increase in its utilization for product development. Therefore, this study assessed the chemical, functional and pasting properties and the microbial and aflatoxin content of HQCF being sold in Lusaka markets. Nine samples of HQCF (coded CM 01 to 09) were collected from supermarkets, one major open market, and one cassava processing centre. The samples were analyzed for chemical, functional and pasting properties and the microbial and aflatoxin content using standard laboratory methods. Samples CM 01, CM 08, and CM 09 had starch content above 60%, while CM 02 to CM 07 had starch slightly above 40%. The mean value of bulk density (BD) was 0.51 ± 25.49 g ml −1 , dispersibility 68 ± 2.63%, swelling power (SP) 7.84 ± 0.76%, solubility index 135.80 ± 18.8%, and water absorption capacity (WAC) 6.28 ± 32.49%. The mean value for the peak viscosity was 437.46 ± 94.12 RVU, trough viscosity 217.55 ± 27.41 RVU, breakdown viscosity ABOUT THE AUTHORS