کبری احمدی چاشمی

Light-emitting diodes (LEDs) can be used as a useful alternative to in vitro culture of various plant species, which not only accelerates plantlet growth and development but also reduces illumination costs. Here, the effects of different light treatments (fluorescent (control), blue LED, red LED, 70% blue/30% red, 70% red/30% blue and SMD lights) on protocorm-like bodies (PLB) growth and development, photosynthetic pigments, antioxidant enzyme activity, and the content of protein and soluble sugars of Phalaenopsis pulcherrima obtained from protocorm explants on ½ MS (Murashige and Skoog) or VW (Vacin and Went) with or without growth regulators (IBA+BAP) were evaluated. The results showed that LED and SMD treatments improved the induction and growth of PLBs compared to fluorescent treatments, which had the highest numbers of PLBs and biomass under blue and red LED light, respectively. Under the same light treatments, the highest numbers of PLBs and biomass were obtained on ½ MS+IBA+BAP. Compared to fluorescent light, LED and SMD lights increased the content of photosynthetic pigments. Among the culture media used, the highest content of photosynthetic pigments was observed on ½MS+IBA+BAP. Compared with fluorescent treatment, a significant increase in the activity of antioxidant enzymes and the content of protein and soluble sugars was observed under LED and SMD treatments, with the largest increase recorded under blue LED. Therefore, our results proved that the use of LEDs can be a practical and effective way to increase the induction of PLBs and improve photosynthetic pigments in the in vitro culture of P. pulcherrima.