Abstract: We studied the effect of light quality on seed germination and seedling growth of the endangered plant Emmenopterys henryi by setting eight light quality treatments including the 940 nm(far red), 850 nm(far red), 730 nm(far red), 630 nm(red), 610 nm(orange), 590 nm(yellow), 525 nm(green), 460 nm(blue) and a nature light as CK, and setting six light quality treatment include 730, 630, 610, 590, 525 and 460 nm, respectively. The results showed that no seed germinate under 940 and 850 nm, and only 1.33% seeds germinate under 730 nm. The germination percent under 525 nm was significantly higher than that under other treatments include natural light control, and there was no significant difference between the final germination percent under natural light and that under 610 and 590 nm. The final germination rate under 460 and 610 nm was significantly lower than that of other treatments. At 120 d, the dry weight of the seedlings was 590 nm > 630 nm > 610 nm > 730 nm > 525 nm > 460 nm. At 120 d, the dry weight of the seedlings under 590 nm was significantly higher than that under other light treatments. The relative growth rate under 630 nm was significantly higher than that of other treatments between 30-90 d, and that under 590 nm was significantly higher than that of other treatments between 90-120 d. It was significantly higher than other treatments at 460 nm between 120-150 and 150-180 d. Root mass ratio was between 0.17-0.25 on the 30th day of treatment, and with no significant difference between treatments. Root mass ratio under 460 nm was significantly higher than that of other treatments on the 30th day of treatment. At 30 d, stem mass ratio under 730 nm was significantly higher than that of other treatments. Leaf mass ratio in each treatment was between 0.53-0.68 on the 30th day of treatment, and there was no significant difference between the treatments.

Key words: light quality, Emmenopterys henryi, seed germination, seedling growth, rare and endangered plants