# Cultivation of _Solanum Lycopersicum_ under Glass Coated with Nanosized Upconversion Luminophore
## 2 Materials and Methods  
Preparation of Photoluminophore Nanoparticles and Investigation of their Properties: The synthesis of upconversion nanopowders with the nominal composition Sr\({}_{0.910}\)Yb\({}_{0.075}\)Er\({}_{0.015}\)F\({}_{2.090}\) was carried out by co-precipitation from aqueous nitrate solutions under ambient conditions, followed by low-temperature drying at 45 \({}^{\circ}\)C and high-temperature annealing at 600 \({}^{\circ}\)C, according to a previously published protocol [48]. To manufacture the photoconversion composites, a 7% solution of nanoparticles in acetone mixed with the liquid component of the fluoroplate polymer was used [26]. A photoconversion film (PCF) containing luminescent nanoparticles was formed on the glass surface using a spray gun. X-ray pattern diffraction (XRD) was performed on a BRUKER D8 ADVANCE diffractometer (Billerica, Massachusetts, USA) with CuK\(\alpha\) radiation. The unit cell parameters (a) were calculated in a fluorite structure (Fm-3m space group) using POWDER 2.0 software. The morphology and particle size of the nanoparticles were determined using a Carl Zeiss NVision 40 microscope (Zeiss AG, Oberkochen, Germany) connected with an Oxford Instruments XMAX (80 mm\({}^{2}\)) set-up (Oxford Instruments _plc_, Abingdon, UK) (using ImageJ software). The hydrodynamic diameter and zeta potential distribution of the nanoparticles were measured with a Zetasizer Ultra (Malvern Panalytical, Malvern, UK). The upconversion luminescence spectra in the visible range were recorded using a fiber-optic spectrometer USB2000 (OceanOptics, Orlando, Florida, USA). The sample was placed inside the integrating sphere Cintra 4040 (GBC Scientific, Braeside, Victoria, Australia) and irradiated using a 50 mW IR light diode, which emits in the region of 960-985 nm with a maximum at 975 nm. The upconversion emission and the scattered laser radiation were collected by the fiber and delivered to the spectrometer. Plant Material and Growth Conditions: _Solanum Lycopersicum_ plants were used in the study. The plants were grown from seeds. Before the experiments, all plants were grown in a 16 h light/8 h dark cycle at 25-26 \({}^{\circ}\)C and at a weak light intensity (PPFD (400 nm-700 nm) and PFD (350 nm-800 nm) were 70 \(\upmu\)mol photon s\({}^{-1}\) m\({}^{-2}\) and 140 \(\upmu\)mol photon s\({}^{-1}\) m\({}^{-2}\), respectively). At the seventh leaf stage, both experiment and control plants were placed under glass coated with a fluoroplate polymer with or without photoconversion nanoparticles. A UVA component (\(\lambda\) = 370 nm, PFD = 10 umol photon s\({}^{-1}\) m\({}^{-2}\)) was added to the illumination spectrum. The leaf area was determined using the GreenImage software developed by our team [26]. The content of chlorophyll in the leaves was determined using a CL-01 chlorophyll content meter (Hansatech Instruments, Norfolk, UK). The number of leaves and the stem length were determined manually. The light intensity was measured using a PG200N Spectral PAR Meter (UPRtek, Zhunan, Miaoli, Taiwan). Chlorophyll Fluorescence (ChlF) Measurement: Before the experiments (treatments and measurements), both tomato plants and leaves were kept for 60 min in the dark at a temperature of 25-26 \({}^{\circ}\)C. The kinetics of photoinduced changes in the ChlF yield (\(\Delta\)F) related to the photoreduction of the primary electron acceptor, Q\({}_{\Delta}\), were measured on a non-cut leaf at room temperature with a DUAL-PAM-100 fluorometer (Walz, Eichenring, Effeltrich, Germany). To measure the maximum quantum yield of PS2 photochemistry ((Fm \(-\) F\({}_{0}\))/Fm, where F\({}_{0}\) is the initial fluorescence value and Fm is the maximum fluorescence value) and ChlF parameters after light adaptation (10 min, \(\lambda\) = 625 nm, 250 umol photon s\({}^{-1}\) m\({}^{-2}\)), the samples were illuminated with a saturating 500 ms flash (\(\lambda\) = 625 nm, 12,000 umol photon s\({}^{-1}\) m\({}^{-2}\)). The calculation of the ChlF parameters was performed using DualPAM software [49].