Effects of New Far-red Light Irradiation on Seed Germination and Seedling Growth of Rice

From perspective of plant light control development，promotion effect of far-red light LED packaged with new phosphor on rice seed germination and seedling growth was researched.（Y，Gd）3（Ga，Sc）5O12：Cr3+ far-red phosphor was directly packaged into far-red light LED used as experimental light source.450 nm blue light emitted by LED chip was converted into 730 nm far-red light.Comparative irradiation experiment of far-red light LED and white light LED were designed on three rice varieties.Germination rate，germination potential，germination index，root length，plant height，stem diameter and dry matter mass were observed in seed germination and seedling growth of three rice varieties.Germination parameters of rice seeds irradiated by far-red light LED were significantly improved.Germination potential increased by 6.38%～16.20%.Germination rate increased by 2.81%～10.33%.Germination index increased by 24.12%～30.84%.The far-red LED irradiation also promoted development of rice seedlings.Root length，plant height and stem diameter of rice seedling increased by 3.01%～22.96%，14.58%～14.68% and 14.50%～14.74%.Growth rate of dry matter mass was about 2.22%～6.06%.The new far-red light LED irradiation is an effective way to promote seed germination efficiency and seedling growth of rice.The research provides a theoretical support for light regulation of rice seed germination and seedling growth，and opens up a new space for development of photosynthetic agriculture and semiconductor lighting industry.