This experiment was conducted at theInternational Institute of Tropical Agriculture (IITA), Ibadan. The objective of the study was to contribute to the understanding of Dioscorea rotundata maintained in vitro and field to observe if there could be any variability in their genetic material due to their different storage conditions by genotyping 43 accessions from in vitro and field populations using 11 microsatellite markers and 25 morphological descriptors to access variability within and between field accessions. Diversity structure was assessed through Principal Component Analysis, Clustering Analysis by Unweighted pair group Arithmetic mean average (UPGMA) and Analysis of molecular variance. This provided a unique opportunity where genetic integrity of Dioscorea rotundata clonal collection maintained in vitro for the past years was confirmed by a side-by-side comparison of the same accessions from the field. The results confirmed that some plantlets within the same accessions maintained in the field showed phenotypic variability. However, molecular comparison proved that duplicate and unique plantlets within the same accession to be genetically the same and further revealed that of the 43 accessions of Dioscorea rotundata investigated, 33 were true-to-type on the basis of band patterns across the primers and genetic distance, while 10 accessions were off-type. This could be as a result of somaclonal variation.

My profound gratitude goes to my institution supervisor Dr. E.A.Okon, for his scientific and constructive criticism throughout this research period. My inestimable and forever grateful thanks go to Dr. David Dekeoyer my International Institute of Tropical Agriculture (IITA) supervisor, who provided the funds for this research and also redesigned the topic to meet farmers demands. My profound thanks to Dr. R. Bhattacharjee for her training, technical support, guidance, constructive criticism during ...

Agronomy; Genetic Improvement; Plant Breeding; Plant Genetic Resources; Plant Production; Tissue Culture; Yam

yams; dioscorea rotundata; genotypes; storage; nigeria; genetic variation; tissue culture

Africa; West Africa

Nigeria

Headquarters and Western Africa Hub