Clonal micropropagation of news cassava varieties (manihot esculenta crantz) assisted by inter-retrotransposon amplified polymorphism and retrotransposon-microsatellite amplified polymorphism markers

Current assay has established protocols for micropropagation of three cassava varieties (Manihot esculenta) of commercial and industrial interest, and index the plants for CsCMV virus. The molecular markers based on retrotransposons LTRs (IRAP and REMAP markers) were employed to test the hypothesis that varieties with greater genetic similarity can develop in the same culture medium while varieties with smaller genetic similarity should require different culture media. Meristem-tips of the three varieties were inoculated in four concentrations of naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA) in the MS culture medium. After the establishment of the meristem-tip, the plantlets were transferred to media supplemented with higher cytokinin (6BA) and auxins (NAA and IBA) concentrations containing gibberellic acid for faster development. The Fécula Branca variety showed 100% of regenerated plants in the medium containing IBA, while the IPR-União variety showed 100% of regenerated plants in the medium containing NAA. Use of the IRAP and REMAP markers showed that plants with greater genetic similarity can develop in the same culture medium while varieties showing the lowest similarity coefficient generated plantlets in culture medium containing different auxin types. So that the use of IRAP and REMAP markers may be indicated as a preliminary strategy to program the in vitro cultivation of the genotypes with greater genetic similarity in media supplemented with the same combination of growth regulators.