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Rice is an important staple food crop that feeds over half of the global population and has become the cereal that provides a major source of calories for the urban and rural poor in Africa. This work aimed to evaluate the morphological of rice (Oryza sativa and Oryza glaberrima) germplasm. In the present study, 14 quantitative traits were used across 48 accessions or genotypes obtained from Central Agricultural Research Institute (CARI), Liberia and Plant Genetic Resources Research Institute (PGRRI), Ghana. In this research, Completely Randomized Design was conducted to study the genetic variability among the 48 genotypes or accessions obtained from CARI, Liberia and PGRRI, Ghana. Field data taken included 14 quantitative traits scored using the IRRI descriptor list. Analysis of variance revealed highly significant difference (P≤ 0.01) among the accessions for all quantitative traits studied. Four significant principal components analysis were identified and accounted for 55.3%. PC1 had Eigen-value of 18.5%, whereas PC2 accounted for Eigen-value of 14.5%. PC3 contributed 12.2% whereas PC4 had 10.1%. Correlation analysis indicated the length of ligule was highly significant and positive leaf width blade. Similar observation was made with grain length and length of ligule. Some accessions in the biplot showed longer vector distances, while shorter vector distances were observed referencing PC1; Gh1578 recorded the longest vector distances while Gh1526 and LAC 23-1, recorded the moderate distances from the vector origin at the similarity coefficients at 90%. The highly distant genetic diversity was found between ACSS37 and ACSS1 from Ghana and Liberia. Cluster X was the largest of all the clusters while Clusters VII and VIII were the second largest clusters with seven accessions each. The outcome of this study should be useful for the management of the germplasm conservation and future rice genetic improvement. However, all the accessions may be cultivated over time at different locations on the field to ascertain their stability and purity. Key words: Correlation, morphological, quantitative, qualitative, accessions.

Rice is an important staple food crop that feeds over half of the global population and it has become the cereal that provides a major source of calories for the urban and rural poor in Africa. This research aimed to use simple sequence repeat (SSR) markers to evaluate the genetic diversity in rice (Oryza sativa and Oryza glaberrima) germplasm as breeding method. In the present study, 16 SSR markers were used across 48 genotypes or accessions obtained from Central Agricultural Research Institute (CARI), Suakoko, Liberia and Plant Genetic Resources Research Institute (PGRRI), Bunso, Ghana. DNA was extracted from 48 plants per accession without bulking to check the purity of the accession using the 16 SSR markers. Sixteen primers were acquired out of 20 primers which showed DNA amplification and polymorphism among the 48 rice accessions. The numbers of alleles detected by these 16 primers ranged from 1 to 16 with a mean of 5.25, while polymorphism information content (PIC) ranged from 0.06 to 0.66 with a mean of 0.35. The SSR markers were highly informative as generated by the power marker V3.25 software. The unweight pair group method with arithmetic averages (UPGMA) cluster dendrogram generated based on the 16 SSR markers grouped the accessions into 11 main clusters. At the similarity coefficients of 90%, the highly distance genetic diversity was found between 2 accessions; ACSS37 and ACSS1. Cluster X was the largest of all the clusters, while clusters VII and VIII were the second largest clusters with 7 accessions each. The outcome of this study should be useful to manage the gremplasm conservation and future rice genetic improvement. Key words: Germplasm, genetic diversity, molecular markers, polymorphism, sequence repeat.

This experiment was carried out to determine the genotypic variation among rice (Oryza sativa) accessions using simple sequence repeats (SSR) markers. In the present study, a total of 12 SSR markers were used across 87 rice accessions from six countries. NTSYS-pc and PowerMarker software were used for data analysis. Six primers out of these 12 primers showed DNA amplification and polymorphism among the 87 rice accessions. The number of alleles detected by these six primers ranged from 2 to 9 with an average of 6.83 while polymorphism information content (PIC) ranged from 0.34 to 0.79 with an average of 0.55. The unweighted pair group method with arithmetic averages (UPGMA) cluster dendrogram generated based on the six SSR markers grouped the accessions into 4 clusters with 41% similarity coefficient. Accessions from these four clusters have late maturity, green basal leaf sheath colour, no awn and fewer tillers, respectively. This experiment has proven that even a small number of SSR markers are effective in assessing genetic diversity in rice. The genetic diversity revealed by the SSR markers in this study would be very important to select potentially good genotypes for future rice improvement programmes. Key words: Dendrogram, genetic diversity, molecular markers, rice.