Effects of Light-emitting Diodes (LEDs) on Stomatal Ultrastructure, Leaf Morphology, and Genetic Stability in Musa acuminata (AAA) cv. Red Banana Plants

The red banana (Musa acuminata) is valued for its nutritional, agronomic, food science and technological uses, and therefore continues to be the subject of research aimed at sustainable utilisation. Micropropagation makes an important contribution to its production, as it enables the mass production of healthy plants with the desired characteristics within a few months. Despite extensive use of light-emitting diodes (LEDs) in banana micropropagation, there is limited integrated evidence on how specific LED spectra influence genetic stability in Musa acuminata cv. red banana. Regenerated Musa acuminata cv. red banana plantlets were established using Murashige and Skoog medium supplemented with 2 µM Thidiazuron (TDZ) under six (6) different LED spectra treatments; white (400–700 nm), blue (440 nm), red (660 nm), far-red (720 nm) mint-white (500–599 nm) and blue + red (440 nm + 660 nm). Stomatal research revealed that white LED provided the highest stomatal density, while far-red and mint-white LED provided the lowest. Blue LED increased stomatal width and length, while mint white LED produced the highest length-to-width ratio. Anatomical analysis showed that mint-white and red LEDs affected both the abaxial epidermis and adaxial hypodermis, while white, blue, blue-red, and red LEDs produced well-differentiated palisades and spongy parenchyma. Genetic stability analysis was performed on the in vitro plants of Musa acuminata cv. red banana. Twenty (20) primers of each SCoT, ISSR and DAMD molecular marker were used to assess the genetic stability of the six (6) samples of Musa acuminata cv. red banana. This study revealed that inter simple sequence repeats (ISSR) and directed amplification of minisatellite DNA (DAMD) markers (DNA primers) are sufficient in determining the polymorphism and monomorphism percentage among the samples. SCoT markers showed 92.74% monomorphism, ISSR markers showed 95.57% of monomorphism whereas DAMD markers showed 84.44% monomorphism. Polymorphism of 15.56% was the highest observed under DAMD markers. However, the combine molecular markers showed 91.12% monomorphism and a Polymorphism of 8.88%. This indicates that certain wavelengths of LEDs help to maintain genetic stability and improve morphological characteristics of micropropagated red banana plants, providing an energy-saving and cost-effective method for mass propagation with minimal somaclonal variation.