VIEW ARTICLE

Letter to the Editor

Response to Comments by Peet and Hunt on the van der Kamp-Tait Susceptibility Model for Resistance Selection. B. J. van der Kamp, Department of Forest Services, University of British Columbia, Vancouver. Accepted for Publication 17 July 1996. Phytopathology 86:1008-1009. Copyright 1996 The American Phytopathological Society. doi:10.1094/Phyto-86-1008.

In 1990, van der Kamp and Tait (5) presented a model that accounted for the observed variation in disease severity of western gall rust (Endocronartium harknessii (J.P. Moore) Hirat.) on lodgepole pine (Pinus contorta Douglas) in terms of the variation in relative susceptibility of pine to the rust. Later, van der Kamp (4) used this model to explore the limits to selection for resistance when the number of discrete infections per plant is low. Peet and Hunt (3) recently questioned some of the arguments as well as the practical significance of the results of van der Kamp (4). In responding to Peet and Hunt's comments I want to address three issues raised by them. These concern the meaning of "perfect knowledge" as used in van der Kamp (4); the magnitude of the loss of resistance arising from the lack of perfect knowledge; and the manner in which the model of van der Kamp and Tait (5) can be used to compare host populations.