Effects of the anther smut fungus Microbotryum violaceum on host life-history patterns in Silene latifolia (Caryophyllaceae)
Shykoff, J.A.; Kaltz, O.
International Journal of Plant Sciences 158(2): 164-171
ISSN/ISBN: 1058-5893 DOI: 10.2307/2475013
The effects of the anther smut fungus Microbotryum violaceum on the life history of the catchfly Silene latifolia were examined. Four maternal sibships of S. latifolia showed no difference in susceptibility to disease caused by 3 different fungal strains. The 3 strains were equally successful in terms of infection and sporulation. The disease affected host phenotype by retarding flowering in males that initiated flowering in their first season and by increasing the number of flowers formed by both males and females. Different fungal strains differentially affected flower production, suggesting genetic variability in natural fungal populations. Diseased plants were more likely than healthy ones to begin flowering in their first growing season, possibly due to phenotype manipulation by the fungus. The sex ratio of the maternal sibships showed a significant female bias, with females having higher infection rates than males.