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We report antimicrobial potential of extracts of roots of Triclisia subcordata and whole plant of Heinsia crinita used as components of various herbal portions in ethnomedine in South West Nigeria to treat acute urinogenital infections and infertility. Methanol and hexane extracts of each plant were obtained by maceration and tested for antimicrobial activity using agar diffusion and microbroth dilution techniques. The extracts were tested against strains of Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and fungi including four species of Candida. The study showed that extracts of H. crinita and T. subcordata exhibited profound antibacterial activity against the typed and clinical isolates obtained from patients with STD and meningitis. High antifungal activity, particularly against the Candida species was noted as Candida species are implicated in candidiasis and vaginal thrush. Generally, the methanol extract was more effective than the hexane extracts on the test micro-organisms. The study justifies the ethnopharmacological uses of these medicinal plants for treatment of microbial infections.

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Parkia biglobosa (Jacq.) is an important leguminous tree crop in the African Savannahs useful to the natives where it is found, for domestic use. Previous diversity studies on this tree crop had been majorly on morphological and biochemical analysis. In order to capture the maximum diversity not obtained by previous research, the study aimed at evaluating the genetic diversity of accessions of this crop in the different agroecological zones in Nigeria using RAPD markers. A total of 81 scorable bands with an average of 8.1 bands per primer were amplified among the accessions studied. Intrazonal genetic diversity analysis showed a percentage polymorphism with a range of 11.11% to 65.43% among the agroecological zones studied. Although, gene diversity was highest within Humid forest agroecological zone, a low genetic distance and high genetic similarity between the agroecological zones were observed. Cluster analysis indicated six main groups of which four groups had single accessions while the two groups clustered the remaining accessions, indicating a narrowed genetic base from the 23 accessions studied.

An increase in the average global temperature and drought is anticipated in sub-Saharan Africa (SSA) as a result of climate change. Therefore, early white quality protein maize (QPM) hybrids with tolerance to combined drought and heat stress (CDHS) as well as low soil nitrogen (low-nitrogen) have the potential to mitigate the adverse effects of climate change. Ninety-six early QPM hybrids and four checks were evaluated in Nigeria for two years under CDHS, low-nitrogen, and in optimal environments. The objectives of this study were to determine the gene action conditioning grain yield, assess the performance of the early QPM inbred lines and identify high yielding and stable QPM hybrids under CDHS, low-nitrogen and optimal environment conditions. There was preponderance of the non-additive gene action over the additive in the inheritance of grain yield under CDHS environment conditions, while additive gene action was more important for grain yield in a low-nitrogen environment. TZEQI 6 was confirmed as an inbred tester under low N while TZEQI 113 × TZEQI 6 was identified as a single-cross tester under low-nitrogen environments. Plant and ear aspects were the primary contributors to grain yield under CDHS and low-nitrogen environments. TZEQI 6 × TZEQI 228 and the check TZEQI 39 × TZEQI 44 were the highest yielding under each stress environment and across environments. Hybrid TZEQI 210 × TZEQI 188 was the most stable across environments and should be tested on-farm and commercialized in SSA.

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Maize production in the savannas of sub-Saharan Africa (SSA) is constrained by the low nitrogen in the soils. The identification of quantitative trait loci (QTL) conferring tolerance to low soil nitrogen (low-N) is crucial for the successful breeding of high-yielding QPM maize genotypes under low-N conditions. The objective of this study was to identify QTLs significantly associated with grain yield and other low-N tolerance-related traits under low-N. The phenotypic data of 140 early-maturing white quality protein maize (QPM) inbred lines were evaluated under low-N. The inbred lines were genotyped using 49,185 DArTseq markers, from which 7599 markers were filtered for population structure analysis and genome-wide association study (GWAS). The inbred lines were grouped into two major clusters based on the population structure analysis. The GWAS identified 24, 3, 10, and 3 significant SNPs respectively associated with grain yield, stay-green characteristic, and plant and ear aspects, under low-N. Sixteen SNP markers were physically located in proximity to 32 putative genes associated with grain yield, stay-green characteristic, and plant and ear aspects. The putative genes GRMZM2G127139, GRMZM5G848945, GRMZM2G031331, GRMZM2G003493, GRMZM2G067964, GRMZM2G180254, on chromosomes 1, 2, 8, and 10 were involved in cellular nitrogen assimilation and biosynthesis, normal plant growth and development, nitrogen assimilation, and disease resistance. Following the validation of the markers, the putative candidate genes and SNPs could be used as genomic markers for marker-assisted selection, to facilitate genetic gains for low-N tolerance in maize production.

The cultivation of fonio in the Western Africa has been greatly hindered by the low amount of rainfall. Crop failure due to drought has been widely reported in Nigeria, which has led to research on different crops with paucity of information on fonio. The present study evaluated six drought genotypes of fonio to determine their physiological and biochemical responses under drought stress conditions. Fonio seeds were planted for a period of 3 weeks and subjected to drought. WUE decreased under drought stress particularly in the P21 genotype, while the RSR significantly increased for all evaluated genotypes. Drought stress seems to enhance the lipid peroxidation and free amino acid activities in the 6 evaluated genotypes, whereas it reduced the proline activities in 4 out of the 6 genotypes. At the early and the late stage, the highest lipid peroxidation was recorded in P25 and P21 respectively. The SOD activities varied at the early and the late stage under drought stress conditions, particularly for the P25, which showed higher level of SOD activities (= 10 folds higher than the control group at the late stage). The activities of CAT and GR for all genotypes studied were not affected by these stressful conditions. However, the APX activity was preferentially reduced in some genotypes, while the remaining ones were unchanged. In conclusion, difference in the physiochemical responses to drought reflects the differences in the ability of the genotypes to withstand varying degrees of drought. The increase in SOD activities might be a frontline defence to counter the increase observed in lipid peroxidation content caused by the reduction in CAT activities under droughtconditionsn.