Coffee plays an important role in the global economy, human health and society. It is one of the major cash crops constituting the backbone of the Nigerian economy before the emergence and re-emergence of petroleum oil. Molecular markers are reliable and valuable tool for analyzing polymorphism, screening and selection of desirable genotypes in breeding programs. The study aimed at determining the genetic diversity among coffee genotypes. Fifty genotypes of coffee (Coffea spp) collected from Cocoa Research Institute of Nigeria (CRIN) germplasm were assessed using 12 simple sequence repeat (SSR) markers. The findings revealed that polymorphic information content (PIC) ranged between 0.311 and 0.882 with an average of 0.545. The gene diversity (0.602) was high and the Unweighted Pair Group Method of Analysis using arithmetic averages (UPGMA) dendrogram grouped the genotypes into four major clusters with subclusters. The results revealed high levels of polymorphism indicating genetic diversity and confirm uniqueness among the coffee genotypes.

The analysis of yield data of eighteen accessions of "egusi" melon across four environments was determined. Genotype main effects and genotype x environment interaction (GGE biplot) method has been described as a very efficient tool for the analyses of multi-environment yield trial of crop varieties, especially where there exists a genotype x environment interaction. Thus, eighteen accessions of "egusi" melon (Citrullus lanatus) were evaluated in four environments in Southwest Nigeria. Strong genotype x environment interaction was confirmed. Among the accessions, DL99/75, DL 99/76 and DD98/506 performed best in Abeokuta 2 environment while L1, DD98/4, DD98/3, 131DA and L4 performed best in Abeokuta 1, Ilaro 1 and Ilaro 2. Accession DD98/550, DD98/7, DD98/533, DD98/511, DD95/549, L3, DL99/71, V2, L2 and L6 did not perform well in all the environments. GGE biplot also ranked the accessions in their order of greater value. Accession DL99/75 was ranked first followed by DD98/506 and the least performed accession was DD98/511.

Cacao (Theobroma cacao L.) is an important commodity tree crop which produces the cocoa bean, a major source of income for most West African countries and many smallholder farmers. Declining yield of cacao is a major limitation to cocoa production in Nigeria. This study aimed at determining the correlations of the phenotypic traits that were related in the yield of the cacao genotypes. Nine cacao hybrids produced from some high-yielding parents in the research farm of Cocoa Research Institute of Nigeria, Ibadan, Nigeria were evaluated from 2012 through 2017 in Owena (7°11’ N, 5°1’ E), Ondo state, Nigeria. Character Correlations and Path Coefficient Analysis were used in the description of the performance of the genotypes. The study concluded that significant genotypic and phenotypic correlations existed among many of the pairs of the fruit and bean characters with one another and with pod index, suggesting a complex contribution of these characters either positively or negatively to growth and yield in cacao, and that fruit and bean traits are determinants of yield in cacao.