37°C, the highest values were obtained at temperatures of 31-32°C with PFDs of 800 and 2000
p, mol m-2 s-~. High light intensities are thus well tolerated by this crop. This is confirmed by the
fact that apical leaves made a large contribution to total photosynthesis, even though they were
exposed to higher PFDs. Our data confirm that Lilium shows good acclimation to high light
conditions, although it is sensitive to high temperatures. As critical conditions occur infrequently
during the plant crop cycle, shading may be restricted to the early vegetative growth phases after
transplanting, when the plants are more sensitive to high temperatures. As shading reduces
transpiration and soil evaporation, it may be used to reduce irrigation requirements of the crop.