ISSN:
1365-3059
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Variation for virulence was examined amongst 20 field collections of Plasmodiophora brassicae from France. Out of the 10 brassica lines tested, seven reacted differentially to inoculation; of these, two oilseed rape cultivars exhibited previously unreported differential responses. Some of the differential lines used previously to classify pathotypes of P. brassicae were susceptible to all collections, suggesting that pathogen populations in France may be different from those reported elsewhere. Good pathotype discrimination was obtained using a set of three cultivars of Brassica napus. Five pathotypes, P1, P2, P3, P4 and P5, were detected and their occurrence was unrelated to host type. Pathogenic variation amongst 17 single-spore isolates derived from three field collections was studied, and five pathotypes were identified. Four isolates were classified as pathotype P1, pathogenic on all three differential hosts, and eight as pathotype P4, pathogenic on none of the three differentials. The five other isolates were classified as pathotypes P3, P6 and P7, the latter two expressing patterns of reaction not observed for field collections. The fractionation of different individual pathotypes from one original spore suspension confirmed the genetic heterogeneity of field populations of P. brassicae.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-3059.1996.d01-155.x
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