In eastern Belgium, diploid and tetraploid knapweeds (Centaurea jacea L. s. l.) show a parapatric distribution with a contact zone. To compare the success of inter- and intra-cytotype crosses, and to ...

IN Centaurea Jacea, the flower-heads of the same stem, as far as I have seen, are always of the same form, but different stems of the same locality often present astonishing difference in their flower ...

Plant Systematics and Evolution, Vol. 298, No. 7 (August 2012), pp. 1349-1360 (12 pages) A population of Centaurea weldeniana was discovered recently near Wien (Vienna). The species is reported from ...

Diversity is one major factor driving plant productivity in temperate grasslands. Although decomposers like earthworms are known to affect plant productivity, interacting effects of plant diversity ...

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