Effects of LED light quality on the growth and development of tissue culture seedling

The effects of light quality on root induction and growth of in vitro plants differed with different wavelengths, and the effects of light quality depended on plant genotype and rooting material concentration. Red light promotes the formation of adventitious roots in tissue culture seedlings such as anthurium, phalaenopsis, monarch flower and ground cover chrysanthemum. Papaya tissue culture seedlings had the shortest length under blue light; red and blue mixed light had a certain promoting effect on the root growth of sweet potato tissue culture seedlings. However, under the irradiation of monochromatic red light, the root system of tissue culture seedlings was abnormal in morphology, and the transplanting survival rate was low, while blue light was beneficial to improve the root vigor in the later stage, which could promote the accumulation of dry matter, reduce the water content, and prevent the occurrence of plant vitrification. The root vigor of chrysanthemums irradiated with monochromatic red light was low, and the transplanted survival rate was only 75%, while the transplanted tissue culture seedlings under the combination of red and blue light all survived. Compared with the control, the root length and root vitality of Phalaenopsis Phalaenopsis treated with the combination of LEDs with far-red light increased significantly. Oncidium tissue culture seedlings had the longest root length under the combined red and blue light, but the shortest length under the fluorescent light.

The LED light source used in the tissue culture stage will affect the growth and survival of tissue culture seedlings after outdoor transplantation. The combined red and blue LED light source used in the indoor tissue culture stage can improve the survival rate of tissue culture seedlings of strawberry, white palm and chrysanthemum and promote the growth of seedlings after transplantation. Therefore, for plant tissue culture seedlings that are difficult to take root, the pretreatment of red light in the early stage can improve the rooting rate and the number of roots, and then transfer to a certain ratio of red light, blue light and far-red light for cultivation to promote root growth and development. And improve root vitality, thereby improving the adaptability of tissue culture seedling transplanting.