Effect of Composted Organic Waste on <i>Miscanthus sinensis</i> Andersson Yield, Morphological Characteristics and Chlorophyll Fluorescence and Content

The aim of this research was to determine the impact of composted mushroom substrate and composted municipal waste on the quality and yield of <i>Miscanthus sinensis</i> Andersson biomass. The plant was grown on anthropogenic soil, cultured earth type and hortisol subtype, with a pH of 6.81. Before planting rhizomes, experimental plots were treated with composted mushroom substrate and composted municipal waste, applied separately or in combination, each dose introducing 170 N kg·ha⁻¹ to the soil. During the experiment, observations of plant development and growth were carried out, and the yield was determined. Each growing season’s measurements were taken of the grass height, the number and diameter of stems and the number of leaf blades and of nodes per stem. In order to determine the level of plant stress, relative chlorophyll content and chlorophyll fluorescence parameters were determined. The measurements were carried out in a non-invasive way, using the SPAD-502 chlorophyll meter and OS30p+ plant stress meter. For the research hypothesis, it was assumed that the one-time addition of composted mushroom substrate and composted municipal waste to the soil would increase yields. The experiment also aimed to assess the impact of both types of compost on the yield and morphological characteristics of <i>Miscanthus sinensis.</i> Its yields increased steadily, and, in the third year of cultivation, were higher by 52%. The highest average yields were noted on plots fertilized only with composted mushroom substrate (KPP_100%), with 8.44 Mg·ha⁻¹ DM, and with compost from municipal waste (KOM_100%), with 7.91 Mg·ha⁻¹ DM. The experience presents a solution to the problem of increasing amounts of organic waste and represents an improvement in cultivation techniques to increase crop yields, improve their quality and increase resistance to biotic and abiotic stress. This paper highlights the possibility of applying environmentally friendly organic waste materials to energy crops used as a sustainable energy source.