NUTRITION LEVEL OF MOTHER PLANTATIONS OF VEGETATIVE APPLE-TREE ROOTSTOCKS M.9 AND M.26

Achievement of high productivity of mother plantations of rootstocks requires that the mother plants are provided with optimum supply of nutrients. So far that branch of production has not seen an estimation of the level of nutrition and of fertilisation requirements. In the years 1998-2002 a study was conducted at two production nursery farms of vegetative apple-tree rootstocks situated in the Lublin region. The experiment comprised model mother plantations of two apple-tree rootstocks with the greatest economic importance - M.9 T337 and M.26. In the course of the experiment chemical analyses of the soil (humus, potassium, phosphorus, magnesium, calcium) were conducted in four soil horizons: I - 0-25 cm, II - 25-50 cm, III - 50-75 cm, IV - 75-100 cm, as well as analyses of the chemical composition (nitrogen, potassium, phosphorus, magnesium, calcium) of leaves, shoots, adventitious roots and root stumps. The soil analyses revealed that changes in the chemical composition within the soil profile were similar: with increase in depth there was a decrease in the levels of humus, potassium, phosphorus and calcium, and an increase in that of magnesium. The chemical composition of leaves and shoots of both rootstock clones did not differ significantly, only the level of calcium in the leaves of rootstock M.9 was significantly higher than that in M.26. The organs of the mother plants (leaves, shoots, roots, root stumps) were characterised by the highest uptake of nitrogen, followed by that of potassium, calcium and magnesium.