Efficacy of Event MON 87460 in drought-tolerant maize hybrids under optimal and managed drought-stress in eastern and southern africa.

Background: Frequent drought events due to climate change have become a major threat to maize (Zea mays L.) production and food security in Africa. Genetic engineering is one of the ways of improving drought tolerance through gene introgression to reduce the impact of drought stress in maize production.

Performance of Bt maize event MON810 in controlling maize stem borers and in Uganda.

Stem borers are major insect pests of maize in Uganda. A study was conducted in 2014-2016 to assess the performance of Bt hybrids expressing Cry1Ab (event MON810) against the two major stem borer species in Uganda - the African stem borer () and the spotted stem borer () - under artificial infestation. The study comprised 14 non-commercialized hybrids, including seven pairs of Bt and non-Bt hybrids (isolines), three non-Bt commercial hybrids and a conventional stem borer resistant check.

Evaluation of early-generation tropical maize testcrosses for grain-yield potential and weevil ( Motschulsky) resistance.

Smallholder maize farmers in Africa experience pre- and post-harvest production stresses either individually or in combination at different stages of the crop cycle. The maize weevil is among the major post-harvest storage pests. A strategy to address this problem is to develop and promote high yielding maize germplasm with resistance to multiple stresses.

Grain-yield stability among tropical maize hybrids derived from doubled-haploid inbred lines under random drought stress and optimum moisture conditions.

Drought is a devastating environmental stress in agriculture and hence a common target of plant breeding. A review of breeding progress on drought tolerance shows that, to a certain extent, selection for high yield in stress-free conditions indirectly improves yield in water-limiting conditions. The objectives of this study were to () assess the genotype × environment (GE) interaction for grain yield (GY) and other agronomic traits for maize ( L.

Combining ability and testcross performance of drought-tolerant maize inbred lines under stress and non-stress environments in Kenya.

Drought and poor soil fertility are among the major abiotic stresses affecting maize productivity in sub-Saharan Africa. Maize breeding efforts at the International Maize and Wheat Improvement Center (CIMMYT) have focused on incorporating drought stress tolerance and nitrogen-use efficiency (NUE) into tropical maize germplasm. The objectives of this study were to estimate the general combining ability (GCA) and specific combining ability (SCA) of selected maize inbred lines under drought stress (DS), low-nitrogen (LN) and optimum moisture and nitrogen (optimum) conditions, and to assess the yield potential and stability of experimental hybrids under these management conditions.

Genetic analysis of tropical maize inbred lines for resistance to maize lethal necrosis disease.

Maize lethal necrosis (MLN) disease is a recent outbreak in eastern Africa and has emerged as a significant threat to maize production in the region. The disease is caused by the co-infection of Maize chlorotic mottle virus and any member of potyviridae family. A total of 28 maize inbred lines with varying levels of tolerance to MLN were crossed in a half-diallel mating design, and the resulting 340 F crosses and four commercial checks were evaluated under MLN artificial inoculation at Naivasha, Kenya in 2015 and 2016 using an alpha lattice design with two replications.

Resistance of -maize (MON810) against the stem borers (Fuller) and (Swinhoe) and its yield performance in Kenya.

A study was conducted to assess the performance of maize hybrids with event MON810 (-hybrids) against the maize stem borer (Fuller) in a biosafety greenhouse (BGH) and against the spotted stem borer (Swinhoe) under confined field trials (CFT) in Kenya for three seasons during 2013-2014. The study comprised 14 non-commercialized hybrids (seven pairs of near-isogenic and non- hybrids) and four non-Bt commercial hybrids. Each plant was artificially infested twice with 10 first instar larvae.

Performance and grain yield stability of maize populations developed using marker-assisted recurrent selection and pedigree selection procedures.

A marker-assisted recurrent selection (MARS) program was undertaken in sub-Saharan Africa to improve grain yield under drought-stress in 10 biparental tropical maize populations. The objectives of the present study were to evaluate the performance of CS-derived hybrids obtained after three MARS cycles (one cycle of recombination (C), followed by two generations of selfing (S), and to study yield stability under both drought-stress (DS) and well-watered (WW) conditions. For each of the 10 populations, we evaluated hybrids developed by crossing 47-74 CS lines advanced through MARS, the best five S lines developed through pedigree selection, and the founder parents with a single-cross tester from a complementary heterotic group.

Regulatory challenges for GM crops in developing economies: the African experience.

Globally, transgenic or genetically modified (GM) crops are considered regulated products that are subject to regulatory oversight during trans-boundary movement, testing and environmental release. In Africa, regulations for transgenic crops are based on the outcomes of the historic Earth Summit Conference held in Rio, Brazil two decades ago, namely, the adoption of the Convention on Biological Diversity (CBD) and the subsequent adoption of the Cartagena Protocol on Biosafety. To exploit the potential benefits of transgenic crops while safeguarding the potential risks on human health and environment, most African countries have signed and ratified the CBD and the Cartagena Protocol on Biosafety.

Assessment of concentrations of iron and zinc and bioavailable iron in grains of early-maturing tropical maize varieties.

Twenty elite early-maturing (75-90 days) tropical maize varieties grown in three diverse agroecologies in West Africa were evaluated to identify varieties with high kernel-Fe and -Zn and bioavailable Fe levels. Bioavailable iron was assessed using an in vitro digestion/Caco-2 cell model. Significant (P < 0.