Mineral composition of leaf sap and its relation to leaf morphology in pear cultivar 'Rocha'.

摘要

From the digital silhouettes of leaf samples collected in 12 pear (Pyrus communis) cv. 'Rocha' orchards in Portugal in three consecutive years (2004-06) several measurements were taken with an image recognition programme and some simple morphometric indices were calculated. These indices were taken as a group of variables and canonical correlations analyses were performed using the nutrient concentrations in leaf sap, or ratios thereof, as the second group of variables. Significant values were obtained for the first and second canonical correlations. This indicates a strong influence of the sap mineral composition in determining the variability of the morphology of leaves, affecting both their size (measured through the area) and shape (represented by proportions between measurements). The significance of these results is discussed from the point of view of using morphometric measurements as a tool to evaluate the physiological state of the trees and provide early indications of sub-clinical, nutritional imbalances.