Evaluation of Leaf Contours of the Leaf Lettuce “Greenwave” Using an Elliptic Fourier Descriptor

To investigate the effects of different types irradiation on growth and morphological characteristics leaf lettuce (Lactuca sativa L. var. crispa “Greenwave”), a quantitative analysis contour using an elliptic Fourier descriptor (EFD) was carried out together with conventional measurement methods. Two experiments were conducted to test treatments. Experiment 1 investigated monochromatic/alternating/simultaneous red/blue irradiation, 2 determined random variations in photosynthetic photon flux density (PPFD) compared that constant light. The consistent those previous studies, where shoot fresh weights monochromatic alternating irradiations larger than simultaneous irradiations. EFD showed length petiole under longer more apparent irradiation. In 2, both methods could hardly detect any differences PPFD. These results suggested fluctuating PPFD within certain limits PFAL may have little effect growth.