Influence of a pulsed (flashing) light-emitting diode (LED) phyto-irradiator on the efficiency of rooting of garden strawberry micro-cuttings in vitro

Abstract

Abstract All greenhouse phyto-irradiators implement a constant regime of plant irradiation. For example, phyto-irradiators turn on at 6 am and turn off at 10 pm. The article contains the results of a study of the influence of pulsed (flashing) light on the growth and development of meristemic plants of garden strawberry varieties ‘Brighton’ and ‘Korona’ in vitro. The ability to use flashing light is based on the features of photosynthesis, which includes light-dependent and light-independent (dark) reactions. A flashing LED phyto-irradiator and a continuously operating fluorescent irradiator (control sample) were compared. Experiments have shown that the use of flashing LED phyto-irradiator increased the rooting rate of strawberry micro-cuttings by 5-10%, depending on the varieties. For the variety ‘Korona’ there was an increase in the number of fully developed leaves to 7.2 pieces (6.0 pieces in the control sample) and, as a consequence, an increase in the leaf surface area of microplants from 262.2 mm2 to 348.0 mm2. For the ‘Brighton’ variety, everything was the other way around: under the flashing LED phyto-irradiator, the number of fully developed leaves decreased to 4.5 pieces (5.6 pieces in the control sample). The use of a flashing LED phyto-irradiator prevented the elongation of microplants in both varieties. At the end of the experiment, all strawberry microplants were rooted and met the standard requirements for rosette height, number of fully developed leaves, and root length.