FIGURE LEGENDS
Figure 1. Global radiation (up) and photoperiod (down) occurred during the cultivated cardoon growing season (October-April) at the Catania experimental station. 1: from 1st to 10th; 2: from 11th to 20th; 3: from 21st to 28th, 30th or 31st.
Figure 2. Quantification of total sesquiterpene lactone, cynaropycrin and cynaratriol content from cultivated cardoon ’Bianco gigante’ leaf extracts in two different harvest times as affected by light stress. Control: 0% of shading; Light stress: 60% of shading. H Jan: harvest time at January 9th; H Apr: harvest time at April 14th. Different letters indicate statistical significance for P ≤0.05.
Figure 3. Quantification of minor sesquiterpene lactones (aguerin B, grosheimin, 11,13-dihydroxi-8-deoxygrosheimin, deacylcynaropicrin and 11,13-dihydro-deacylcynaropicrin) content from cultivated cardoon ’Bianco gigante’ leaf extracts in two different harvest times as affected by light stress. Control: 0% of shading; Light stress: 60% of shading. H Jan: harvest time at January 9th; H Apr: harvest time at April 14th. Different letters indicate statistical significance for P ≤0.05.
Figure 4. Effect of light stress, in two different harvest times, on the phytotoxicity of cultivated cardoon ’Bianco gigante’ leaf extracts expressed as inhibition of wheat coleoptile elongation. Control: 0% of shading; Light stress: 60% of shading. H Jan: harvest time at January 9th; H Apr: harvest time at April 14th. Values are expressed as percentage difference from control. Each bar means ± standard deviation.
Figure 5. Effect of extract concentration on the phytotoxicity of cultivated cardoon ’Bianco gigante’ leaf extracts expressed as inhibition of Amaranthus retroflexus and Portulaca oleracea seed germination, root and shoot length. H Jan: harvest time at January 9th; H Apr: harvest time at April 14th. Different letters indicate statistical significance for P ≤0.05. Each bar means ± standard deviation.