Impact of Light Quality on in vitro Potato Microtubers Formation

In the present study, the influence of three-wide spectrum light-emitting diodes (LEDs), emitting warm light AP67 (moderate blue and red and low red:far-red), AP673L (high red and high red:far-red) and G2 (high red and low red:far-red) with different colours mixing blue, green, red and far-red was used for micropropagation of three Polish potato cultivars; ‘Aruba’, ‘Oberon’ and ‘Skawa’. The planlets were grown in a growth chamber with a 16-h photoperiod. The photosynthetic photon flux density was 30 μmol m-2 s-1. The tissue culture medium for shoot proliferation was a standard MS-based medium. Microtuberization was observed on MS medium supplemented with higher sugar content (40 m g/L-1). Light quality affected the number of microtubers (MTs) per plantlet, the volume (cm3) of MTs, the fresh weight (mg) of MTs, and the width (mm) of MTs. Different light qualities did not affect morphological parameters, including length (mm), perimeter (mm), and crosssection area (mm2) of microtubers, whereas the highest number of microtuber were detected under the effect of AP67 light quality. The morphological parameters mostly depended on cultivar. The lowest number of microtubers was observed in the G2 treatment. In conclusion, ‘Aruba’ and ‘Oberon’ with AP67 and AP673L, as well as LED lighting systems, were determined as most suitable in terms of the MT count per plantlet. Also, these variables were most suitable for MT volume (cm3), fresh weight (mg), and width (mm).