Sequence alignment and phylogenetic analyses

DNA sequences were edited and assembled using the BioEdit software (http://www.mbio.ncsu.edu/BioEdit/bioedit.html). The ITS sequence for all three Pythiogeton manoomin isolates was identical. Therefore, the sequences of Pythiogeton manoomin isolate BV1 was submitted to GenBank ({"type":"entrez-nucleotide","attrs":{"text":"KF719169","term_id":"568816324","term_text":"KF719169"}}KF719169). The ITS sequence ({"type":"entrez-nucleotide","attrs":{"text":"JQ610201","term_id":"399221653","term_text":"JQ610201"}}JQ610201) of Pythium aphanidermatum was selected as an outgroup. Sequences were aligned using ClustalW, and a phylogenetic tree was constructed with MEGA 5.03 (Tamura et al. 2011), using the maximum parsimony method with 1000 bootstrap replication and evolutionary distance analyzed according to Tamura-Nei model (Tamura et al. 2011). The maximum parsimony tree was obtained using the Tree-Bisection-Regrafting algorithm with search level 5 in which the initial trees were obtained by the random addition of sequences (Nei and Kumar 2000). All positions containing gaps and missing data were eliminated. The aligned sequence data set was deposited in TreeBASE (No. 24,156).