FROM FIELD TO FILM - RAPID SEQUENCING METHODS FOR FIELD-COLLECTED PLANT-SPECIES

Methods that have proven effective in the rapid extinction of plant DN A, PCR amplification and sequencing of ribosomal and chloroplast genes are presented. Techniques that can be used under field conditions to preserve DNA for subsequent extraction are reviewed. Tissues that are fresh, heat-desiccated, silica gel-desiccated and cetyltrimethylammoni um bromide (CTAB) buffer preserved are compared for DNA quality and qu antity. The ''delayed CTAB'' method yields high molecular weight DNA, thereby providing an alternative to preservation using silica gel. Opt imized methodologies for PCR amplification and double-stranded sequenc ing of the product are detailed including gel purification of PCR prod ucts using DEAE membranes.