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Centaurea jacea

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Common name: Brown Knapweed or Brownray Knapweed

Symptoms induced in controlled conditions (fumigation with ozone)

Fumigation of Centaurea jacea with increased ozone levels in Open Top Chambers induced light-brown stippling and enhanced leaf reddening. While stippling is an ozone-specific response, reddening is not, as it can also occur in plants grown in filterted air (control).

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