Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 13 July 2021 doi:10.20944/preprints202107.0305.v1 Cytological and molecular characterization for ploidy determination in yams (Dioscorea spp.) Cobes Gatarira1,2, Lucia Sládeková3, Alžběta Němečková3, Denisa Šimoníková3, Rajneesh Paliwal1, Asrat Asfaw1, Michael Abberton1, Gueye Badara1, Robert Asiedu1, Jana Čížková3, Eva Hřibová3, Jaroslav Doležel3, David DeKoeyer4, Victor Adetimirin5 and Ranjana Bhattacharjee1* 1International Institute of Tropical Agriculture, PMB 5320, Ibadan, Nigeria 2Pan African University, Institute of Life and Earth Sciences, University of Ibadan, Ibadan, Nigeria 3Institute of Experimental Botany of the Czech Academy of Sciences, Centre of the Region Hana for Biotechnological and Agricultural Research, Šlechtitelů 31, CZ-77900 Olomouc, Czech Republic 4Agriculture and Agri-Food Research Centres and Collections, PO Box 20280, Fredericton, New Brunswick, E3B 4Z7, Canada 5Department of Crop and Horticultural Sciences, University of Ibadan, Ibadan, Nigeria *Corresponding author:
[email protected] Abstract Yam (Dioscorea spp.) is a monocotyledonous herbaceous vine plant grown in the tropics and subtropics. It is a multi-species plant with varied intra- and interspecific ploidy levels. Of the 600 species, 11 are cultivated staple supporting the livelihood of over 300 million people. The paucity of information on ploidy and the genomic constitution is a significant challenge to the crop’s genetic improvement through crossbreeding. The objective of this study was to investigate the ploidy levels of 236 accessions across six cultivated and two wild species using chromosome counting, flow cytometry and genotyping-based ploidy determination methods. Results obtained from chromosome counting and genotyping-based ploidy determination were in agreement. In majority of the accessions, chromosome counting and flow cytometry were congruent, allowing future rapid screening of ploidy levels using flow cytometry.