In a microcosm experiment, I tested how species composition, species richness, and community age affect the susceptibility of grassland communities to invasion by a noxious weed (Centaurea solstitialis L.). I also examined how these factors influenced Centaurea’s impact on the rest of the plant community. When grown in monoculture, eight species found in California’s grasslands differed widely ...

At local scales, it has often been found that invasibility decreases with increasing resident plant diversity. However, whether resident community diversity similarly resists invasion by alien versus native species is seldom studied. We examined this issue by invading constructed native plant assemblages that varied in species and functional richness with invasive alien or native Asteraceae spe...

The genus Centaurea with an extensive background in Iranian traditional medicine represents more than 70 species in Iran that some of them are endemic to Iran. A variety of secondary metabolites has been isolated from this genus thus far. Sesquiterpene lactones and flavonoids have been reported as main compounds of C.bruguierana. Methanolic extract and different fractions of the whole fruiting ...

Background and objectives: The genus Centaurea from the Asteraceae family is one of the most widely distributed plant genera worldwide that has been extensively used in folk medicine for hundreds of years. The present study is the first investigation about the principal constituents of Centaurea albonitens Turrill which is native to Iran. Methods: The aerial parts of C. albonitens were extracte...

Understanding the factors that alter competitive interactions and coexistence between plants is a key issue in ecological research. A pot experiment was conducted to test the effects of root interaction and arbuscular mycorrhizal fungi (AMF) inoculation on the interspecies competition between Trifolium repens and Lolium perenne under different proportions of mixed sowing by the combination trea...