Evaluation location: Puerto Rico, United States
Plant material for DNA extractions was collected from three separate Musa spp. field plantings on the TARS research farm in Isabela, PR as well as from the tissue culture collection. Leaf samples were collected from all four replicate plants in the established field germplasm collection, from representative plants from a Sigatoka leaf spot disease evaluation plot as well as from a core set of Musa spp. plants being evaluate for morphological traits. As plants in the in vitro tissue culture are micro-propagated from one initial initiated apical meristem, a single representative plantlet for each accession was used for DNA extraction. Additional DNA samples were graciously provided by Dr. Jaroslav Dolezel, on a cost recovery basis and as part of the GMGC service from the Laboratory of Molecular Cytogenetics and Cytometry of the Institute of experimental Botany, Prage, Czech Republic. These reference DNA sample duplicates were included in the analysis as references for specific subgroups not represented in the existing collection as well as a separate source of DNA to confirm matching with synonymous clones and reproducibility as of technique. DNA samples were then shipped to USDA-ARS Genomics and Bioinformatics Research Unit in Stoneville, MS for PCR and subsequent electrophoresis. Twenty two microsatellite makers were used to fingerprint replicated plants for 184 unique accessions of the current USDA-ARS TARS Musa spp. germplasm collection. SSR primer sequences were developed (Crouch et al. 1998; Lagoda et al. 1998; Hippolyte et al. 2010) and selected for their allelic diversity and for usefulness in distinguishing diverse Musa spp.