BIOLOGICAL ACTIVITY OF SOIL AND PRODUCTIVITY OF ECHINACEA UNDER REPEATED CULTIVATION

Abstract

Representatives of the genus Echinacea Moench have been successfully used worldwide for over 300 years due to their medicinal properties. Various medicinal preparations for humans and animals, dietary supplements, and feeds are made from the herb and rhizomes with roots. The unique phytochemical complex and the absence of side effects allow the production of immunostimulatory, anti-inflammatory, and antiviral drugs. In Ukraine, two species have been introduced into cultivation: Echinacea purpurea (L.) Moench and Echinacea pallida (Nutt.) Nutt., which are successfully cultivated on farms. Despite the long period of study, some aspects of Echinacea agronomy require further research. One of them is repeated cultivation. The aim of our research was to study the productivity and biological activity of the soil under conditions of repeated cultivation of Echinacea purpurea and Echinacea pallida. For this purpose, experiments were set up in which each species was grown in two cycles of two years (repeated cultivation) and two years of Echinacea pallida after two years of Echinacea purpurea and vice versa. The assessment of soil biological activity by direct biotesting on a test culture indicates that repeated cultivation of Echinacea purpurea inhibited growth processes, while Echinacea pallida, when grown after Echinacea purpurea, positively affected the test object. Determination of soil catalytic activity shows that when growing Echinacea pallida, the biological activity of the soil was higher than that of Echinacea purpurea under different experimental schemes. In repeated cultivation of Echinacea purpurea higher catalase activity was determined in spring, while in summer and autumn, it was higher in plots where Echinacea pallida was grown. The conducted studies indicate that with repeated cultivation, the main quantitative and qualitative indicators that ensure the formation of Echinacea productivity significantly decrease. Echinacea purpurea formed fewer leaves per plant (by 31.5 pcs.), plant mass (by 43.3 g), and total photosynthetic surface area (by 293.5 cm²). The response of Echinacea pallida to repeated cultivation was negative: plant mass decreased by 76.3 g, the number of leaves by 14.7 pcs., inflorescences by 5.1 pcs., and photosynthetic surface area by 18.05 cm². It is suggested that the allelopathic component contributes to the decrease in Echinacea productivity in repeated cultivation. Therefore, in farms growing medicinal plants, it is necessary to avoid prolonged cultivation of Echinacea in one place.