| dc.description.abstract | 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. |
| cg.contributor.acknowledgements | 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 yam molecular diversity study using SSR markers and PAGE system. Because of her professional proficiency, this work is in its present shape. Also, am very much indebted to Dr. Agre Patterne, who supervised this work both the molecular and morphological characterization and most importantly guided me on the data analysis: I pray that God almighty continues to enrich you with more knowledge. My appreciation goes to Mrs. Ibukun Ogunleye for her assistance and support during
my laboratory work. My sincere thanks to Mr. Stanley Nwachukwu, for his assistance both financially and morally during my period in IITA. Also to Mrs. Mary Badejo, the Head of Capacity Development Office (CDO) of IITA, and thefamily of Mr. and Mrs. Dele Thomas, Mr. and Mrs.John Odey, Comfort Onigah for their encouragement, moral and materials support. My sincere thanks also go to Bioscience Center staff members and International Association of Research fellows and scholars (IARSAF), for providing me the platform to study and acquire research skills and knowledge to compete with my colleagues from other parts of the world in plant breeding and genetics. My thanks also go to Mr. Tunde Adeosun, Mr. Alex. O. of the yam breeding unit of IITA Ibadan, for providing me with field accessions and the entire team of the yam breeding unit. Also, Mr. Yemi who guided me and provided all the necessary assistance during my tissue culture work and the entire members and staff of the Genetic Resource Unit (GRU) of IITA. I am very grateful to all my friends and well-wishers, Endurance Asu, Alice A. Ada Deborah, Odey Friday (my typist), Iyabeni A. Jerry, Sabatha Harrison, Evasam, Ndum, Florence,Oyama, and others too numerous to mention, for their important advice, help, and encouragement. Finally, to my parents, Mr. and Mrs. Cosmas Abu, for their love, material support, and most importantly the fate that they have always kept in me. I can’t forget to mention my
brothers, sisters, cousin, aunts, and other relations. May God bless you all!!! Above all, I thank the almighty God for every event of my life!!! |
