Abstract

Attached and detached leaves of 60 potential host species were inoculated in the greenhouse and laboratory with aeciospores of Cronartium ribicola J.C. Fisch. from six Finnish locations and of Cronartium flaccidum (Alb. & Schw.) Wint. from 20 locations in Finland and Sweden in 2011. Candidate hosts represented 16 plant families: Solanaceae, Verbenaceae, Asclepiadaceae, Grossulariaceae, Paeoniaceae, Balsaminaceae, Gentianaceae, Scrophulariaceae, Loasaceae, Tropaeolaceae, Acanthaceae, Myricaceae, Phrymaceae, Plantaginaceae, Orobanchaceae, and Apocynaceae. Inoculations of C. flaccidum produced uredinia after 2 weeks and (or) telia after 4 weeks of incubation on 25 hosts. Inoculation trials identified several new hosts for C. flaccidum in Fennoscandia, namely Impatiens balsamina, Swertia fedtschenkoana, Loasa tricolor, Myrica gale, Verbena canadensis, Saxifraga spp., Paeonia obovata, and Veronica daurica. Myricaceae and Saxifragaceae represent new host families for these rusts. Cronartium ribicola formed uredinia or telia on 10 species: Ribes spp. (7 species/cultivars), Pedicularis palustris subsp. palustris, Bartsia alpina, and Loasa triphylla. Results suggest wider alternate host ranges for both C. flaccidum and C. ribicola than previously recognized. Spores were virulent regardless of their source location, suggesting a lack of host-specificity among Fennoscandian populations of Cronartium.

Keywords

alternate hosts; Scots pine blister rust; white pine blister rust

Published in

Botany
2012, Volume: 90, number: 8, pages: 694-703
Publisher: CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS

SLU Authors

• Samils, Berit

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Botany
Forest Science


Publication identifier

DOI: https://doi.org/10.1139/B2012-039

Permanent link to this page (URI)

https://res.slu.se/id/publ/43534