Impact of ultraviolet radiation and drought on the content of biominerals uptake in leaves of barley

In the master's thesis we studied the effect of natural UV radiation and water availability on the biomineral content in barley leaves (Hordeum vulgare L.). We sowed barley in troughs and placed them on an outdoor testing area. Half of the troughs were positioned under roof tiles that let through the entire light spectrum, while the other half were positioned under roof tiles that let through the visible part of the light spectrum and only about 10% of UV radiation. Each group also had two types of water availability; normal watering and drought. For all four treatments of plants, we measured the silicon and calcium content in the leaves, the reflectivity and transmittance of the leaves, as well as content, tissue thickness and structures on the surface of the leaves. We also monitored the physiological state of the plants, pigment content and conditions in the surrounding environment. The results of our studies showed that water availability affected the biomineral content of calcium and silicon in the leaves. UV radiation did not have a statistically significant effect on the content of these two elements in the leaves. The results of potential and actual photochemical effectiveness tests showed that unfavourable water availability and the level of natural UV radiation did not have a negative effect on the plants’ vitality. The results of morphological tests showed the greatest deviations in specific leaf surfaces, which were affected by water availability. We found that neither water availability nor natural UV radiation had an effect on the content of chlorophyll a and b, carotenoids and anthocyanins in the leaves. The transmittance and reflectivity of the leaves were greatest in the visible part of the spectrum