ISSN:
1365-3180
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Glass-faced growth containers were used to study the phenology of three demes of Centaurea maculosa Lam. (Compositae), and the impact of root-mining by the moth Agapeta zoegana (L.) (Lep.: Cochylidae) on rooting intensity. This moth was recently established in North America for the biological control of spotted and diffuse knapweed, C. maculosa and C. diffusa. The life cycle, biomass production and longevity of the diploid European host plant (monocarpic biennial) and the tetraploid North American target species (polycarpic perennial) differed considerably, providing a possible explanation for the rapid spread of the tetraploid species in North America. Compared to controls, plants of German and Canadian origin infested by A. zoegana showed increased root growth during the mining period and after the emergence of the moths. However, no such difference was found in diploid plants of Hungarian origin. The observed plant reactions partly support, therefore, the hypothesis of a nutritionally controlled response to herbivory. Infested plants did not differ in fecundity compared to controls, but root-mining tends to reduce the survival rate of immature plants The consequences for the plant population density are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-3180.1989.tb00847.x
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