LED Light Technology as a Source of Illumination and a Promising Method for Stevia rebaudiana Elite Propagation

Abstract

Effect of light-sources, quality, and intensities on morphogenesis, shoot multiplication, development and roots, and biomass production in Stevia investigated using shoot tips cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of plant growth regulators (PGRs). 2000 Lux intensity provided by fluorescent light lambs was found the most favorable for shoot induction and production, shoot length, number of leaves/explant and also for fresh and dry weights/foliage. Under this light condition, the optimum contents of photosynthetic pigments, cholorophyll a, cholorophyll b, total cholorophyll, and carotenoids recorded. Blue-LED light treatment created growth condition for the highest shoot elongation, leaves number/shoot, leaf fresh weight, leaf dry weight, and photosynthetic pigment production. Cent percent of shoot induction was obtained under red-LED treatment resulting in the largest number of shoot production. Root formation was promoted by 2000 and 3000 Lux intensities of light. However, the 2000 Lux intensity treatment provided the most favorable growth condition permitting generation of largest number of longest roots with maximum fresh/dry weights. Root induction was 100 percent under fluorescent light, the maximum fresh and dry weights of roots were achieved on blue-Led light and red-LED treatment induced the longest roots.