Figure 8.

Growth analyses of Arabidopsis thaliana plants. Plants were grown in the different conditions as indicated. The experiments were carried out with plants of the T₄ generation. Values are the means ± standard error of three biological replicates with 6–12 samples each. Unpaired two-tailed t-tests were used. Significantly different values (P < 0.05) are labelled with an asterisk. AtP, A. thaliana expressing the wild-type phosphoribosylpyrophosphate synthetase (PRS) gene; AtM, A. thaliana expressing a mutant form of the PRS gene; numbers indicate the identity of the individual primary transformant. (a) Rosette fresh weight of Arabidopsis plants grown with adequate nutrients. Plants were grown in growth chambers (8 h day at 145 µmol/m²/s, 20 °C, 60% relative humidity; 16 h night at 18 °C) in pots of 6 cm in diameter filled with a substrate containing high nutrient concentrations. Plants were harvested 5 weeks after transfer to soil. (b) Rosette fresh weight of Arabidopsis plants grown with limiting nutrients. Plants were grown with the same growth conditions and in parallel with plants in (a), but the substrate mixture contained low nutrient concentrations as described in ‘Experimental procedures’. Plants were harvested 5 weeks after transfer to soil.