Pythiogeton manoomin, a new species causing root and basal stalk rot of wild rice in the United States

Figures & data

Table 1. Averaged daily colony radial growth and standard deviation, in mm, on Rye B agar. Three plates were used for each temperature, and the experiment was repeated three times.

Pythiogeton manoomin isolates	Averages radial colony growth (mm day^−1)
	4°C	12°C	15°C	18°C	21°C	25°C	28°C	31°C	34°C
BV1	0.33 ± 0.58	4.00 ± 2.65	5.34 ± 3.87	12.11 ± 3.06	16.11 ± 1.93	23.44 ± 3.21	18.56 ± 3.03	7.22 ± 3.06	0.67 ± 0.58
BV2	0.67 ± 0.58	3.33 ± 2.65	5.11 ± 2.52	10.89 ± 3.21	15.44 ± 2.52	22.89 ± 2.79	18.11 ± 3.07	8.33 ± 2.00	0.67 ± 0.58
BV3	0.00 ± 0.00	2.89 ± 1.15	6.11 ± 2.52	11.89 ± 2.52	14.33 ± 2.00	22.56 ± 2.79	17.89 ± 2.51	7.78 ± 4.16	0.33 ± 0.58

Figure 1. Pythiogeton manoomin. (a), Colony on PDA; (b–c), hyphae and appressoria (arrows) on RSA; (d–e), sporangia, terminal or intercalary and short distance from the end of supporting hyphae; (f–g), globose (arrow) and ellipsoid sporangia, (h–i), reniform sporangia, (j), bilobate sporangia, (k–l), pyriform sporangia, (m–n), globose (arrow) and ovoid sporangia; (o), chlamydospores, (p–q), sporangia initiating formation of the discharge tube (arrowheads), (r), formation of zoospores from a protoplasm mass, and, (s), discharged zoospores; (t), empty sporangia, showing empty discharge tubes (arrows). Scale bars = 20 μM.

Figure 2. The Maximum Parsimony tree of Pythiogeton species with Pythium aphanidermatum as the outgroup based on ITS sequences. Numbers on the branches represent bootstrap values obtained from 1000 replications.