Australasian Plant Pathology (1993) 22, 143-148

A.D. Heritage, P. Pistillo and J.T. Wood (1993)
Comparison of Haro-isolines with traditional soybean race differentials to distinguish races of Phytophthora sojae
Australasian Plant Pathology 22 (4), 143-148
Abstract: Use of a modified set of commercial soyabean cultivar differentials to discriminate between physiological races of P. sojae frequently provides intermediate results. New isolines, in which defined Rps resistance genes have been incorporated into the soyabean cultivar Harosoy, were examined to evaluate their effectiveness as race differentials with selected field isolates of the fungus from irrigated soyabean crops. A numerical method for computing the fit of results from an inoculation test to sets of expected differential reactions, or hypothetical reaction for new races, is described. Use of the new set of differentials, based on Harosoy isolines, did not improve the overall race determination of 8 selected field isolates of P. sojae, whether based on erect seedlings or confined lesion development after hypocotyl inoculation. In fact, computations using the traditional differential set generally gave a closer fit to a race. However, the presence of an additional discriminating gene, Rps5, in one of the isolines would prove useful if additional races of the pathogen arise in Australian soyabean crops.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Phytophthora sojae	Soybean (Glycine max)