The response of Å ampion trees growing on different rootstocks to applied organic mulches and mycorrhizal substrate in the orchard

The aim of the study was to evaluate the effects of using organic mulches: barley straw, chipped pine bark, forest humus, compost, cow manure, commercial peat moss, and commercial mycorrhizal substrate on the growth and yield of Šampion apple trees produced on M26, P2, M9, and P22 rootstocks. The investigations were conducted using Šampion apple trees grown on chosen rootstocks and substrates: barley straw, chipped pine bark, forest humus, compost, cow manure, commercial peat moss substrate, and commercial mycorrhizal substrate. Apple trees grown on all analysed rootstocks reached the greatest height on compost and cow manure mulches, and the biggest trunk diameter was achieved by trees growing on the straw mulch. The greatest number (P < 0.05) of fruits was produced by trees growing on the forest humus mulch, especially those grafted on rootstocks M9 and P22. The forest humus, compost, and cow manure mulches had a beneficial effect on the content of mineral elements in the soil and leaves of Šampion trees growing on all rootstocks. The humus, compost, and cow manure mulches had a positive effect on the growth of the apple trees. The organic mulches increased the number apples and the content of minerals in the soil and leaves.