EFFECT OF TRACE ELEMENT SPRAYS AND FRITTED TRACE ELEMENTS ON THE GROWTH AND Mn, Zn, Cu AND B CONTENTS OF YOUNG ‘BRAESTAR’ / ‘M793’ AND ‘SONGOLD’ / ‘MARIANNA’ TREES IN SAND CULTURE

In a two-year pot trial, year-old “Braestar”/”M793” apple, and ‘Songold’/’Marianna’ plum trees were subjected to a combination of foliar sprays containing manganese sulphate, zinc oxide, Solubor, copper oxychloride and urea at rates, respectively, of 1.0, 0.5, 1.0, 0.25 and 2.5 g.L^-1 water, and soil-applied fritted trace elements (FTE). The carrier (FTE-504Fe7) contained 7.5% Mn, 7.0% Zn, 7.0% Cu and 3.8% B, and was mixed into the sand growing medium before planting at rates of FTE equivalent to 0, 100 and 200 g.m^-3. Where FTE was applied to the apple trees at 100 g.m^-3 and foliar sprays were also applied, total tree dry mass (DM) and rootstock DM were significantly (p≤0.05) greater, by 16% and 29%, respectively, than in the control which received no FTE and no sprays.
Sprays without FTE had no significant effect on DM in either fruit kind.
Where FTE was applied with sprays at 200 g.m^-3 the apple stem diameters and total tree DM values were smaller than with FTE at the 100 g.m^-3 application rate, implying oversupply.
In the unsprayed treatments total tree DM in the 100 g.m^-3 and 200 g.m^-3 FTE treatments were, respectively, 9% and 27% less than where no FTE was applied.
Total tree DM in the plum trees was 15% lower in the unsprayed treatment which had been supplied with FTE at 100 g.m^-3 than in the unsprayed, zero-FTE treatment.

IV International Symposium on Mineral Nutrition of Deciduous Fruit Crops

J. Wooldridge

apple, boron, copper, manganese, plum, zinc

https://doi.org/10.17660/ActaHortic.2001.564.39