Kwadwo Ofori

Bio: Kwadwo Ofori is an academic researcher from University of Ghana. The author has contributed to research in topics: Population & Sorghum. The author has an hindex of 13, co-authored 78 publications receiving 582 citations.

Diversity in 113 cowpea [Vigna unguiculata (L) Walp] accessions assessed with 458 SNP markers

Abstract: Single Nucleotide Polymorphism (SNP) markers were used in characterization of 113 cowpea accessions comprising of 108 from Ghana and 5 from abroad. Leaf tissues from plants cultivated at the University of Ghana were genotyped at KBioscience in the United Kingdom. Data was generated for 477 SNPs, out of which 458 revealed polymorphism. The results were used to analyze genetic dissimilarity among the accessions using Darwin 5 software. The markers discriminated among all of the cowpea accessions and the dissimilarity values which ranged from 0.006 to 0.63 were used for factorial plot. Unexpected high levels of heterozygosity were observed on some of the accessions. Accessions known to be closely related clustered together in a dendrogram drawn with WPGMA method. A maximum length sub-tree which comprised of 48 core accessions was constructed. The software package structure was used to separate accessions into three groups, and the programme correctly identified varieties that were known hybrids. The hybrids were those accessions with numerous heterozygous loci. The structure plot showed closely related accessions with similar genome patterns. The SNP markers were more efficient in discriminating among the cowpea germplasm than morphological, seed protein polymorphism and simple sequence repeat studies reported earlier on the same collection.

Adaptive capacity and coping strategies in the face of climate change: A comparative study of communities around two protected areas in the coastal savanna and transitional zones of Ghana

Abstract: Modern productivity-enhancing strategies (MPES) are considered to be some of the best adaptation options available to communities in the face of changing climatic conditions. The adaptive capacity of communities living around two protected areas (Kogyae Strict Nature Reserve and Muni-Pomadze Ramsar Site) in Ghana were assessed in relation to MPES by investigating household accessibility to human, social, natural, financial and physical capital. Information was collected from 249 and 250 respondents in Kogyae and Muni respectively. A logit model was used to find out whether adaptive capacity affected adoption of MPES. In both study areas, indigenous coping strategies such as use of simple farm tools, processing of root/tubers and grains and social grouping were practiced. The MPES practiced included application of fertilizers and other agrochemicals, use of high technology machinery and bunding in rice fields. The mean level of adaptive capacity of farm households was low in both areas; 0.30 and 0.27 in Kogyae and Muni respectively. The adoption of MPES was influenced positively by the level of human and physical capacities and farm size and location of protected area, and negatively by farmers’ participation in off-farm activities. Farmers located in Kogyae were more likely to adopt productivity-enhancing strategies than their counterparts in Muni. Considering that access to the resources within the protected areas is restricted and not legally available to support livelihoods of the fringe communities, we conclude that enhancing access to both human and physical capitals is the way forward for climate change adaptation for these two communities.

Pigeonpea [(Cajanus cajan (L.) Millsp.)] production system, farmers’ preferred traits and implications for variety development and introduction in Benin

Abstract: The success of crop varieties introduction is tightly linked to the uses, biophysical conditions, the cropping systems in which the crop is integrated and farmers’ and consumers’ preferences. In Benin, however, pigeonpea production systems including the cropping systems, marketing, utilizations and preferences have received little attention. This study aimed at analyzing farmers’ practices and constraints related to pigeonpea production as well as identifying farmers’ preferred traits in pigeonpea. The study was conducted in three pigeonpea-growing agroecological zones in Benin. Participatory rural appraisal tools including individual interview (n = 302) and group discussion were used to collect information on production system, constraints and preferred traits. Fisher’s exact test was used to assess the relationship between crop associated with pigeonpea and the growing areas. Based on preferred traits, villages were clustered using UPGMA. Pigeonpea is predominantly grown by men. Approximately 98% of the pigeonpea growers associated pigeonpea with other crops, while 2% of them grew the crop in pure stand. Pigeonpea grown in association with maize (48.7%) was the most encountered cropping system. The type of crops associated with pigeonpea depended on the growing area (P < 0.001), and a high diversity in crops combination was observed in the Department of Couffo. Lack of improved varieties, low productivity and lack of quality seed were major factors constraining pigeonpea production. The pigeonpea seed system was essentially informal with self-saved seed (79%), purchase from fellow farmers or from local markets (12%) and gift/exchange (9%) as seeds sources. Farmers’ preferences traits varied across pigeonpea-growing area, but overall, high yielding, early maturing, and resistance to pod borers were the main reported preferred traits. Our results confirm the importance of pigeonpea both in the cropping systems and in contributing to ensure food security in the growing areas in Benin. Farmers’ varietal preferences were identified. This information is important for designing appropriate strategies for sustainable pigeonpea production. Insight gained into farmers’ preferred traits in pigeonpea varieties will also help in the choice of varieties or advanced breeding materials to be integrated into participatory varietal selection programs in order to improve productivity of the crop in Benin.

Human biochemical genetics

Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Genetic Data Analysis

Abstract: LEARNING The objectives of BIOS 781 are to present: OBJECTIVES: 1. basic population and quantitative genetic principles, including classical genetics, chromosomal theory of inheritance, and meiotic recombination 2. an exposure to QTL mapping methods of complex quantitative traits and linkage methods to detect co-segregation with disease 3. methods for assessing marker-disease linkage disequilibrium, including case-control approaches 4. methods for genome-wide association and stratification control.

An Introduction to Genetic Statistics

Abstract: A reviewer for the Journal of the Royal Statistical Society of England comments \"This is the first book covering in one volume all important topics in genetical statistics.\" Written to provide basic probability ideas in terms of genetic situations, since the theory of genetics is a probability theory; to give a definitive treatment of applications of these ideas to genetic theory; and to describe statistical methods appropriate to the data models that are developed.