The Use of Synthetic Shelters with Integrated Photoluminescent Phosphors for Greenhouse Structures in Rooting the Northern White-Cedar Cuttings

We have explored the effectiveness of using light-correcting covering materials for greenhouse structures when rooting the cuttings of various ornamental forms and varieties of the northern white-cedar (Thuja occidentalis L.). Two types of shelters have been tested: the modified spunbond at a density of 30 g/m2 with a photoluminescent phosphor integrated into its structure at a concentration of 0.8 % and the unmodified spunbond at the same density. Europeum-doped yttrium oxysulfide (Y2O2SEu) has been chosen as a photoluminescent phosphor. We have analyzed 11 varieties and forms of Thuja occidentalis L.: Rheingold, Mr. Bowling Ball, Woodwardii, Tiny Tim, Golden Smaragd, Mirjam, Golden Globe, Danica, Sunkist, Smaragd and Brabant. The response of the indicators of callusogenesis and rhizogenesis to the influence of a transformed light flux has been tested. A positive effect of the use of photoluminescent phosphors in rooting the stem cuttings of the northern white-cedar has been established. An increase in the indicators of regenerative ability and post-regenerative development of the root systems and the aboveground parts of the cuttings has been recorded, such as: the activity of callusogenesis, the number of adventitious roots formed, the length of the leading root, the total length of the root system, the height of the aboveground part and the diameter of the root collar. Callusogenesis has increased from 67.59 ± 2.05 % in the check to 76.81 ± 1.61 % when having integrated the photoluminescent phosphor. The number of adventitious roots formed has increased from 9.64 ± 0.43 to 11.44 ± 0.34 pcs., correspondingly. The total length of the root systems has increased from 64.56 ± 3.70 to 75.52 ± 2.77 cm, correspondingly. One-way analysis of variance confirmed the significance of the differences between the tested forms and varieties in each of the shelter options for most of the tested indicators. Two-way analysis of variance has revealed a significant effect of the positive impact of photoluminescent phosphors on callusogenesis, adventitious root formation, post-regenerative development of the root systems and the aboveground parts of the cuttings.