The Effects of Blue and Red Light on the Hill Reaction of isolated Chloroplasts, Photosynthesis and Saponin Accumulation in Fenugreek Leaves (Trigonella foenum-graecum L.)

Blue light (450 nm) and red light (660 nm) were two specific wavelengths that have essential roles in plant photosynthesis and signals to synthesize plant metabolisms. In the fenugreek plant (Trigonella foenum – graecum L.), various saponins were synthesized in leaves and were used in pharmaceuticals. This study focused on the effects of blue and red light alone or in combination with fluorescent light on isolated chloroplasts, photosynthesis activities and saponin accumulation of fenugreek leaves. The results showed that the blue light increased the Hill reaction, stomatal opening and the ratio of chlorophyll a and b (Chla/b). Otherwise, the red light promoted total chlorophyll content and increased saponin in Fenugreek leaves. In addition, the combination of blue, red and fluorescent light increased photosynthesis activities and maintained plant growth and increased saponin accumulation in Fenugreek leaves.