Articles
EFFECTS OF PEACH ROOT RESIDUES IN SOIL ON GROWTH, WATER RELATIONS AND MINERAL STATUS OF PEACH TREES WITH SPLIT ROOT SYSTEM
Article number
363_12
Pages
93 – 100
Language
Abstract
Decomposing peach root residues depress growth of replanted peach trees, often producing symptoms of leaf wilting and chlorosis.
Water relations and mineral status may therefore be affected by decomposing root residues.
When a tree is growing on a site of an aged peach orchard, part of the root system comes into contact with decomposing residues while the other part develops in areas unexplored by the roots of the previous orchard; it may be that the latter compensates for the depression of growth and funtionality of the former.
In the present study, cv.
Maycrest one-year peach trees grafted on PSA5 peach seedling were individually transplanted in spring with root system split in two 5-1 pots and grown over the summer.
Treatements were as follows: (1) both pots containing virgin soil (control, trt VV); (2) both pots containing virgin soil enriched with 5 g kg-1 of peach root fragments (widespread presence of root residues, trt RR); (3) one pot containing virgin soil and the other containing virgin soil enriched with root residues at the same rate of treatment 2 (localized presence of root residues, trt VR). Throughout the growth season, transpiration was higher in control than in VR and RR treatments.
Pre-dawn leaf water potential was not affected by treatments, while mid-day leaf water potential of trees with localized and widespread presence of root residues was significantly lower than control.
At the end of the trial, shoot and root development was higher in control trees; no differences were found between the localized and widespread presence of root residues.
In VR trees, the presence of root residues in one pot depressed the growth of the other part of the root system growing in the virgin soil.
Leaf and root mineral status was not affected by the presence of root residues.
Our data suggest that the localized presence of decomposing residues in soil are toxic to the whole plant, including the part of the root system that explores virgin soil sites.
The evidence supports the assumption that a poor supply of mineral element in soil is not the likely cause of the growth depression; decomposing root residues impair water uptake and/or transport to leaves, contributing to depression of growth.
Water relations and mineral status may therefore be affected by decomposing root residues.
When a tree is growing on a site of an aged peach orchard, part of the root system comes into contact with decomposing residues while the other part develops in areas unexplored by the roots of the previous orchard; it may be that the latter compensates for the depression of growth and funtionality of the former.
In the present study, cv.
Maycrest one-year peach trees grafted on PSA5 peach seedling were individually transplanted in spring with root system split in two 5-1 pots and grown over the summer.
Treatements were as follows: (1) both pots containing virgin soil (control, trt VV); (2) both pots containing virgin soil enriched with 5 g kg-1 of peach root fragments (widespread presence of root residues, trt RR); (3) one pot containing virgin soil and the other containing virgin soil enriched with root residues at the same rate of treatment 2 (localized presence of root residues, trt VR). Throughout the growth season, transpiration was higher in control than in VR and RR treatments.
Pre-dawn leaf water potential was not affected by treatments, while mid-day leaf water potential of trees with localized and widespread presence of root residues was significantly lower than control.
At the end of the trial, shoot and root development was higher in control trees; no differences were found between the localized and widespread presence of root residues.
In VR trees, the presence of root residues in one pot depressed the growth of the other part of the root system growing in the virgin soil.
Leaf and root mineral status was not affected by the presence of root residues.
Our data suggest that the localized presence of decomposing residues in soil are toxic to the whole plant, including the part of the root system that explores virgin soil sites.
The evidence supports the assumption that a poor supply of mineral element in soil is not the likely cause of the growth depression; decomposing root residues impair water uptake and/or transport to leaves, contributing to depression of growth.
Publication
Authors
M. Tagliavini, B. Marangoni
Keywords
Online Articles (26)