|Title||Effects of continuous spectrum LEDs used in indoor cultivation of two coniferous species Pinus sylvestris L. and Abies borisii-regis Mattf|
|Author(s)||Smirnakou, Sonia; Ouzounis, Theoharis; Radoglou, Kalliopi|
|Source||Scandinavian Journal of Forest Research 32 (2017)2. - ISSN 0282-7581 - p. 115 - 122.|
|Department(s)||Horticulture & Product Physiology|
|Publication type||Refereed Article in a scientific journal|
|Keyword(s)||Controlled environment - light response - light-emitting diode - plant morphology - root growth potential|
The effects of four different continuous spectrum LED light qualities on the growth characteristics of Pinus sylvestris L. (PS) and Abies borisii-regis Mattf. (AB) seedlings were studied. The seedlings were exposed for 35 days inside growth chambers to G2 (high in red and far-red), AP67 (high in blue and far-red), AP67-ARCH (high in green), and NS2 (high in blue including a small percentage in the UV area) LEDs, as well as fluorescent light (FL) as Control. Each species showed a unique light-adapted response. G2 treatment stimulated needle formation of PS seedlings, while AB seedlings were unaffected. Hypocotyl elongation was promoted by FL; however, LEDs resulted in compact plants with greater root development, especially under the AP67-ARCH and AP67 spectra for PS and AB, respectively. In PS, AP67-ARCH and G2 significantly increased dry weight, while AB was affected significantly by AP67 and NS2. Furthermore, root growth potential of both species was better after LED pre-cultivation than the FL. Therefore, the use of continuous spectrum LEDs can enhance desirable quality characteristics of seedlings, which may be advantageous in large scale seedling production for reforestation.