Effect of sugar content of Poa pratensis on Helminthosporium leaf spot
. Physiological and Plant Pathol., 2: 279-287.
DISEASE PROBLEMS -- Anthracnose -- Red thread -- Brown patch -- Rust -- Copper spot -- SAD -- Dollar spot -- Slime mold -- Fairy ring -- Smut -- Gray leaf spot -- Snow mold--gray -- Helminthosporium leaf spot
-- Snow mold--pink -- Necrotic ring spot -- Spring dead spot -- Nematode -- Summer patch -- Powdery mildew -- Pythium blight -- Others: Recommendations: (apply a fungicide, decrease nitrogen fertilization, reseed with resistant cultivars, etc.) 16.
Evaluations of resistance to Helminthosporium leaf spot were performed only at E3 and E4, where natural levels of infection were sufficiently high to discern differences among entries.
One cultivar, PI614817, exhibited an extremely sensitive response to Helminthosporium leaf spot, scoring a 9 in each replication of both environments.
The residual from the full genetic model ([a.sub.i], [bar.h], [h.sub.i], and [s.sub.ij] effects) was statistically significant for each of the other traits except days to maturity and reaction to Helminthosporium leaf spot (Table 1).
For ratings of resistance to Helminthosporium leaf spot (measured only at E3 and E4), only 3% of this total of sums of squares was due to the environmental main effect.
Jumbo had moderate resistance to Helminthosporium leaf spot
disease (caused by Dreschlera spp.), and was considerably more resistant than Surrey.
At the time of its release in 2000, Horizon 314 exhibited excellent resistance to prevalent races of crown rust, and was moderately resistant to Helminthosporium leaf spot
, (caused by Helminthosporium sativum Pam., King & Bakke).
Helminthosporium leaf spot (Bipolaris sorokiniana Sacc.
This application included phenoxy herbicides, which were reported to predispose Kentucky bluegrass to Helminthosporium leaf spot (Hodges, 1980).