Abstract: Light-emitting diodes (LEDs) have gained significant popularity in horticultural crop production due to their ability to enhance plant quality while reducing production costs. Compared to conventional fluorescent (FL) bulbs, LEDs offer advantages such as adjustable light intensity and quality, making them well-suited for commercial micropropagation. This study aimed to assess the growth and development of in vitro ornamental banana plants under various light sources. Two ornamental banana varieties were evaluated. Plantlet length and biomass were greater under LED-1 compared to FL, though not significantly different from LED-2. No significant differences were found in fresh and dry weight of shoots and roots, number of leaves, or root quantity and length among the light treatments. Chlorophyll content was higher under LED lighting. Leaf number and stomatal characteristics (number and size) were greater under FL lighting. These findings suggest that optimizing light quality and intensity can enhance shoot growth and biomass, and highlight the genotype-dependent responses to light sources observed between the two banana varieties.
Keywords: banana; micropropagation; light intensity; light quality; plant growth and development; leaf anatomy
1. Introduction
Light is a key factor influencing in vitro plant morphogenesis [1,2]. A variety of artificial light sources, such as fluorescent lamps, high-pressure sodium lamps, metal halide lamps, and incandescent lamps, have been commonly used in plant tissue culture and the commercial micropropagation of numerous crops [3]. Among these, cool-white fluorescent lamps are the most widely used for micropropagation [4,5]. However, these lamps emit a broad spectrum (350-750 nm), which is not optimal for promoting plant growth. Additionally, fluorescent lights consume more energy, contributing to high operational costs in micropropagation, second only to labor expenses [6,7]. The heat emitted by fluorescent lamps can also lead to plant damage and photo-stress [3]. As a result, more efficient and cost-effective lighting systems are needed to enhance in vitro plant growth and development. Light-emitting diodes (LEDs) have emerged as an attractive alternative, especially in horticulture, and have been successfully applied in space-life support systems [8,9]. More recently, LEDs have been integrated into in vitro plant systems [10]. They offer a more targeted light spectrum, improving the quality of plantlets while reducing per-plant production costs. LEDs also allow precise control over photosynthetically active radiation (PAR), optimizing conditions for plant growth, morphology, and metabolism.