The susceptibility of selected conifer foliage to infection with Phytophthora lateralis

Abstract
The foliage of seven different genera of conifers including ten species and 17 different cultivars was tested for its susceptibility against two isolates of Phytophthora lateralis. Detached green shoot tips were floated in zoospore suspension and the lesion size was assessed after seven days. xCupressocyparis leylandii, Juniperus media and Cedrus deodara were the most resistant hosts whereas Chamaecyparis obtusa was most susceptible. Thuja plicata and occidentalis, Chamaecyparis pisifera and lawsoniana, Taxus baccata and Cupressus macrocarpa were of medium susceptibility. For comparison a small subset of four hosts was also tested for stem susceptibility. The stems of whole potted plants were inoculated with the same two isolates as used for the leaf susceptibility tests. C. lawsoniana was highly susceptible whereas the stems of C. leylandii, T. baccata and T. plicata were all resistant.
Year
2017
Category
Refereed journal