The development of sericulture is closely related to the cultivation of mulberry. Mulberry leaf is the main food material for the silkworms (Bombyx Mori). The mulberry leaves contain all the necessary nutrients to ensure normal growth and productivity of the silkworms. The main aim of the present study is to investigate and analyze the presence of some elements in the mulberry leaves of a new variety and to compare their levels to those of a well-known variety (Vratsa 1). The chemical analysis of the two varieties was performed in the analytical laboratory of Agricultural University – Plovdiv. The concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) were studied. It was concluded that the new mulberry variety contains adequate level of food nutrients required for silkworm diet. Moreover, the analysis shows that the content of most of the tested elements in the new variety significantly exceed those of the variety used as a reference. As the new variety can be planted on weaker soils, its range could be expanded and thus to ensure that even less nutrient-rich soils will be used to the best advantage.
Keywords: Bombyx mori L., Morus alba L., micro elements, macro elements, heavy metals