EFFECT OF SUBSTRATES CONTAINING COMPOSTS WITH THE PARTICIPATION OF MUNICIPAL SEWAGE SLUDGE ON FLOWERING AND MACRONUTRIENT CONTENT IN THE LEAVES OF GARDEN PANSY (Viola × wittrockiana Gams.)

Abstract

The aim of the study was to assess the impact of substrates containing composts made from municipal sewage sludge and straw or sawdust on flowering, leaf greenness index and macronutrient content in the leaves of ‘Fancy Carmine with Blotch’ garden pansy. Two composts, with the following compositions: K I – 70% municipal sewage sludge, 30% rye straw; K II – 70% municipal sewage sludge, 30% coniferous tree sawdust, were used for the preparation of substrates. Six substrates of peat and compost at 25, 50 and 75% (by volume) were prepared. The control object was a peat substrate, pH 5.8–6.0, supplemented with Azofoska at 2.5 g·dm -3 . It has been found that leaf greenness index of pansy increased with an increasing share of compost. Composts involving municipal sewage sludge at the level of 50% had a more positive influence on the abundance of pansy flowering than at 25 and 75%. The content of to tal nitrogen, phosphorus, potassium and sulfur in the leaves increased with increasing the dose of compost. The content of total phosphorus in the leaves at the end of pansy cultivation in compost substrates ranged optimally for this species. In the experiment conducted in 2006, pansies contained more total nitrogen, potassium and sulfur than the flowering pansies planted in 2005.