Genetic Diversity of Wild Rice (Oryza longistaminata) in Ghana

Oryza longistaminata is a wild rice taxon and an excellent source of genetic variation that remains largely unexploited. This study was conducted to understand the genetic diversity between and within O. longistaminata populations, collected from different geographic locations in Ghana. In this study, SSR markers were used to determine the intra-specific variability in O. longistaminata, and how the variation is partitioned within and between different populations. Analysis of molecular variance revealed high levels of polymorphism (95.9%) within the populations. The overall genetic diversity for all the loci in the six populations was high (Shannon's Information Index I = 0.579, Nei's unbiased expected heterozygosity, He = 0.405). Hierarchical partitioning also indicated a high genetic diversity between and within populations, with some level of relatedness between samples taken from the Savannah agroecological area. The high genetic diversity observed in this study offer a great opportunity for screening useful traits among the populations of O. longistaminata in Ghana for rice breeding programs

Effect of Gamma Irradiation on Chlorophyll Content in the Cowpea (Vigna unguiculata (L.) Walp)

The experiment was conducted to study the mutagenic effect of gamma rays on chlorophyll content at three different physiological stages in the cowpea: pre-flowering, flowering and post-flowering. Five sets of cowpea seeds were subjected to individual doses of gamma rays: 400 Gy, 450 Gy, 500 Gy, 600 Gy and 0 Gy. The seeds were sown to raise the M1 generation. The M1 generation seeds were collected and sown in the next season to raise the M2 generation. Leaf chlorophyll content was measured for M2 generation plants. Mean chlorophyll content for pre-flowering stage ranged between 38.9 ± 8.17 (control) and 64.2 ± 6.16 (400 Gy). Flowering stage mean chlorophyll content ranged from 48.3 ± 14.4 (600 Gy) to 99.4 ± 6.22 (450 Gy). Post-harvest chlorophyll mean content ranged between 13.1 ±0.98 (600 Gy) and 38.0 ±1.90 (400 Gy). There were significant differences in treatment effects for pre-flowering (P = 0.021), flowering (P = 0.005) and harvest (P = 0.000). At pre-flowering treatment, treatment 400 Gy scored a significant increase of 64 percent (P = 0.02) above the control. The optimum dose for useful induced mutation for increases in chlorophyll concentration in the cowpea was 400 Gy

SSR-Based Genetic Structure Study of Seventy-Eight Cowpea (Vigna unguiculata (L.) Walp) Genotypes

Seventy-eight cowpea accessions were studied using short sequence repeats (SSR) technique. Genetic structure of these accessions was studied using three SSR polymorphic primers, SSR-6206, SSR-6218 and SSR-6219. A total of eight loci were scored for the three primers with a total of ten alleles. Bayesian clustering method grouped the cowpea genotypes into 4 sub-populations. Ancestral allele frequencies ranged between 0.128 and 0.802, while allele frequencies within sub-populations ranged from 0.001 and 0.997. Allele frequency divergence among sub-populations ranged from 0.145 to 0.406. Expected heterozygosity between individuals in the same sub-population ranged from 0.084 and 0.26, Mean genetic differentiation among sub-populations ranged from 0.374 and 0.687, with a mean geneflow ranging from 0.228 and 0.837. There was relative uniformity within the sub-populations which can be accounted for by independent random genetic drift

Self-reported injuries and correlates among school-going adolescents in three countries in Western sub-Saharan Africa

Background Unintentional injuries among adolescents constitute a significant public health problem globally. Injured adolescents may face negative outcomes ranging from poor academic performance to short- and long-term physical and psychosocial health struggles, and even death. The aim of this study was to estimate the prevalence and describe the correlates and most frequent causes of injuries among school-going adolescents in three West African countries – Benin, Ghana, and Liberia. Methods We analysed self-reported data provided by 8,912 school-going adolescents who participated in the Global School-based Student Health Survey in Ghana (2012), Benin (2016), and Liberia (2017). Students responded to questions on sociodemographic factors, family involvement factors, mental health factors, school environment factors and injury behaviours. Results The overall 12-month prevalence estimate of serious injuries in adolescents was 40.9% (Benin = 27.3%; Ghana = 46.1%; Liberia = 49.2%). The most frequently reported injury type was a broken bone or dislocated joint (33% in Benin), cuts or stab wounds (31.7% in Ghana), and non-specified injuries (35.2% in Liberia). Prevalence of serious injuries was higher among males and increased with age. In the multivariable logistic regression analysis, interpersonal aggression outside the family context (bullying victimisation, engaging in physical fights, and having been physically attacked) emerged as key correlates of increased odds of serious injuries. Conclusion The relatively higher prevalence estimates of serious injury reported in this study underscore the need for the included countries to develop interventions aimed at reducing and preventing physical injuries among adolescents

Bulk genetic characterization of Ghanaian maize landraces using microsatellite markers

Maize (Zea mays L) was first introduced into Ghana over five centuries ago and remains the most important cereal staple, grown in all agro-ecologies across the country. Yield from farmers’ fields are low, which is attributed in part to farmer’s preferences and/or reliance on local landraces for cultivation. Efforts are underway to improve some of these landraces for improved productivity. Seeds of maize landraces cultivated in all agro-ecologies were col¬lected for genetic characterization using a bulked fingerprinting technique and 20 SSR markers. In all, 20 popula¬tions of 15 plants each from Ghana and 4 control populations from Latin America were characterized. The cluster analysis grouped the 20 landraces into two major groups corresponding to the vegetation/climatic conditions of the north and south of the country. Genotypes from Ashanti, which is centrally located, fell into both major clus¬ters, which suggest its importance in maize seed distribution in Ghana and also the diverse climate/vegetation. A Structure analyses grouped the genotypes into two major clusters similar to the UPGMA cluster, and populations were not fully distinct according to F statistics. The results suggest that breeders should make performance data available to seed dealers for better productivity