The effect of light quality on some physiological and biochemical parameters of in vitro propagated petunia cv. Blue star plants

Nia Petrova, Milena Dimitrova, Daniela Dragolova, Maria Rogova, Veneta Kapchina-Toteva

Abstract: Petunia hybrida plants were propagated in vitro by single-node explants on basic MS medium (3.0% sucrose, 0.7% agar), pH adjusted to 5.7 – 5.8. The explants were cultivated in a growth chamber at different combinations of monochromic LED lighting at equal irradiance of 70 μmol.m-2.s-1 at the tops of the plants, 12-h photoperiod, 25/25 °C day/night temperatures and 60 – 70% relative humidity. Three different types of LEDs, emitting in the red (635 nm, R), green (531 nm, G), and blue (463 nm, B) region of the spectrum are used to compose 66: 33% RB and 33: 33: 33% RGB light. After four weeks of cultivation the following characteristics were observed: stem number and length, rooting, callus formation, fresh/dry weight index and malondialdehyde (MDA) levels. P. hy¬brida cultivated on red/blue LED form higher number and longer shoots and higher fresh/dry weight index they also have slightly larger content of MDA than plants exposed to cool white light.

Keywords: light quality; malondialdehyde; Petunia hybrid

Date published: 2017-07-26