Phytophthora cryptogea as a cause of root rot of raspberry in Australia; resistance of raspberry cultivars and control by fungicides

Abstract

Phytophthora cryptogea was isolated from field plantings of the red raspberry cultivars Glen Clova, Canby and Willamette which showed wilting, dieback, stem lesions and root rotting. Pathogenicity of P. cryptogea to raspberry was demonstrated in glasshouse experiments. Twelve cultivars of raspberry were screened for resistance to the disease by growing them in artificially infested soil. Glen Clova and Canby were highly susceptible whilst Chilcotin, Nootka, Haida and Puyallup were resistant. Soil treatments with either metalaxyl, phosphorous acid or fosetyl aluminium controlled the disease. This is the first record of a phytophthora root rot of raspberry in Australia, and the first demonstrating the pathogenicity of P. cryptogea to raspberry.

Phytophthora bilorbang sp. nov., a new species associated with the decline of Rubus anglocandicans (European blackberry) in Western Australia

“…bisheria (Abad et al 2008;Brasier et al 2003a ;Duncan and Kennedy 1987;Ellis et al 1991;Jung et al 2011;Kennedy and Duncan 1995;Washington 1988;Wilcox et al 1993;Wilcox and Latorre 2002). In contrast, many blackberry cultivars appeared to be highly tolerant to Phytophthora.…”

Temporal Aspects of the Development of Root Disease Epidemics

“…Several experiments were analysed from the literature including the effects of soil solarization and artificial heating on the progress of tomato wilt caused by Fusarium oxysporum f.sp. /ycopersicae (Greenberger et al 1987) and the effects of chemical control and cultivar on Phytophthora cryptogea on raspberry (Washington 1988). Soil solarization affected the carrying capacity of disease with a reduction in the asymptote (Ku).…”

Comparison of disease progress curves

“…[Note that the independent variable (days after inoculation) was transformed by subtracting 10 d so that the origin corresponded with the time of inoculation, cf. Washington (1988) where the origin was shown as 10 d prior to inoculation. ]…”

“…There was no evidence for an improvement in the fit to individual curves by letting /c, =t = 0: the F values were Greenberger et al (1987) Figure 4. Observed data, together with estimated logistic curves, with and without common parameters, for two experiments to compare the effects of cultivars and fungicides, respectively, on the progress of disease due to Phytophthora cryptogea over time on raspberry; data from Washington (1988). of disease development on triticale was associated with a delay in the epidemic and a lower asymptote (Fig.…”