Articles
MAPPING THE DISTRIBUTION OF CALCIUM ON APPLE TISSUE WITH PROTON-INDUCED X-RAY EMISSION – AFTER APPLICATION OF ADDITIONAL PRE-HARVEST FOLIAR OR SOIL CALCIUM
Article number
984_42
Pages
347 – 355
Language
English
Abstract
The development of calcium (Ca) deficiencies in the apple fruit are ascribed to a lack of accumulation of Ca in specific areas of the fruit.
Localized deficiencies therefore commonly occur in spite of sufficient levels of total fruit Ca.
A trial was conducted during two consecutive seasons (2008/9 and 2009/10) to evaluate the contribution of either foliar or soil-applied Ca to the localization of Ca in Braeburn apple fruit.
Ca (Ca(NO3)2) was applied either in the form of soil pellets (TropicoteTM) at fruit set or after harvest, or as a series of weekly foliar applications (CalfloTM) between 21 and 70 days after full bloom (dafb). Additional treatments consisting of combinations of these were also applied.
Elemental Ca mapping across the radius of the fruit was achieved via the use of micro-PIXE (particle induced X-ray emission). In all treatments, Ca was concentrated in the skin and core of the fruit, with the lowest values occurring in the outer cortex.
At 80 dafb, Ca was highly associated with vascular bundles in an otherwise homogenous cortex.
Fruit set Ca soil applications consistently resulted in fruit with less Ca at 80 dafb compared to the other treatments.
The prevalence of vascular bundles mostly determined the average Ca concentrations in the core, inner and outer cortex regions and emphasizes the importance of the functionality of vascular bundles throughout the season.
Foliar Ca altered the distribution of Ca in the fruit and resulted in a significant increase in Ca in the outer cortex relative to the core.
Localized deficiencies therefore commonly occur in spite of sufficient levels of total fruit Ca.
A trial was conducted during two consecutive seasons (2008/9 and 2009/10) to evaluate the contribution of either foliar or soil-applied Ca to the localization of Ca in Braeburn apple fruit.
Ca (Ca(NO3)2) was applied either in the form of soil pellets (TropicoteTM) at fruit set or after harvest, or as a series of weekly foliar applications (CalfloTM) between 21 and 70 days after full bloom (dafb). Additional treatments consisting of combinations of these were also applied.
Elemental Ca mapping across the radius of the fruit was achieved via the use of micro-PIXE (particle induced X-ray emission). In all treatments, Ca was concentrated in the skin and core of the fruit, with the lowest values occurring in the outer cortex.
At 80 dafb, Ca was highly associated with vascular bundles in an otherwise homogenous cortex.
Fruit set Ca soil applications consistently resulted in fruit with less Ca at 80 dafb compared to the other treatments.
The prevalence of vascular bundles mostly determined the average Ca concentrations in the core, inner and outer cortex regions and emphasizes the importance of the functionality of vascular bundles throughout the season.
Foliar Ca altered the distribution of Ca in the fruit and resulted in a significant increase in Ca in the outer cortex relative to the core.
Authors
R.E. Wilsdorf, E. Lötze, J. Mesjasz-Przybylowicz, W.J. Przybylowicz
Keywords
elemental mapping, PIXE, X-ray microanalysis, Ca deficiency, Malus domestica
Online Articles (54)