3.1 DNA extraction and PCR amplification from herbarium and contemporary samples
A total of 186 samples from twelve states in the U.S. (n=130), four states in Mexico (n=13), three Central American countries (n=13), four South American countries (n=6), four Caribbean Islands (n=16), Germany (n=3), India (n=3) and The Philippines (n=2) were sequenced and analyzed as noted above. There were varying levels of success for the amplification of each genetic locus among the samples. This was particularly the case for many of the herbarium samples, some of which were more than 100 years old. The ITS region was the most successfully amplified and sequenced, with 168 sequences generated. Whereas 91 sequences were generated for the LSU locus (Table 1).