Articles
MICROBIOLOGICALLY IMPROVED PEAT-BASED MEDIA FOR NURSERY PRODUCTION BY ADDITION OF ARBUSCULAR MYCORRHIZAL FUNGI
Article number
819_49
Pages
403 – 410
Language
English
Abstract
Growing media based on light peat are commonly used in horticultural production.
Although peat possesses a range of positive properties, it may also incur problems.
Structural problems are common in long-term use.
Light peat has a very low anion exchange capacity resulting in leaching of nitrate and phosphorus.
Peat also lacks beneficial symbiotic arbuscular mycorrhizal fungi (AMF) which are important to crops in sustainable systems.
The aim of this study was to investigate the possibilities of developing a microbiologically improved peat-based growing medium optimal for the growth of nursery and landscaping plants.
It was hypothesized that the chemical, physical and biological properties of peat-based growing media can be optimized for high AMF function.
The effects of light and dark Sphagnum peat and dark Carex Bryales peat were studied, as well as their mixtures with minerals like sand, pumice, vermiculite, perlite, clay or zeolite on AMF function were studied in three short-term experiments using daisy as a host plant.
Light Sphagnum peat clearly suppressed the function of AMF, resulting in less growth in AMF-inoculated plants and low AMF root colonisation.
In mixtures with clay, AMF root colonisation was higher, but the effect of AMF on growth was still negative.
However, AMF did not usually affect plant growth negatively when decomposed Sphagnum or Carex Bryales peat was used.
Compared with peat alone, the functioning of AMF was improved, especially in peat mixtures with clay or pumice.
In mixtures of light and dark peat the effect of AMF inoculation was very similar to that obtained in light peat alone.
These results show that the undesirable negative effect of AMF, often observed after inoculation, can at least partly be overcome by using decomposed peats and potting mixes of peat and mineral components, in particular clay.
Although peat possesses a range of positive properties, it may also incur problems.
Structural problems are common in long-term use.
Light peat has a very low anion exchange capacity resulting in leaching of nitrate and phosphorus.
Peat also lacks beneficial symbiotic arbuscular mycorrhizal fungi (AMF) which are important to crops in sustainable systems.
The aim of this study was to investigate the possibilities of developing a microbiologically improved peat-based growing medium optimal for the growth of nursery and landscaping plants.
It was hypothesized that the chemical, physical and biological properties of peat-based growing media can be optimized for high AMF function.
The effects of light and dark Sphagnum peat and dark Carex Bryales peat were studied, as well as their mixtures with minerals like sand, pumice, vermiculite, perlite, clay or zeolite on AMF function were studied in three short-term experiments using daisy as a host plant.
Light Sphagnum peat clearly suppressed the function of AMF, resulting in less growth in AMF-inoculated plants and low AMF root colonisation.
In mixtures with clay, AMF root colonisation was higher, but the effect of AMF on growth was still negative.
However, AMF did not usually affect plant growth negatively when decomposed Sphagnum or Carex Bryales peat was used.
Compared with peat alone, the functioning of AMF was improved, especially in peat mixtures with clay or pumice.
In mixtures of light and dark peat the effect of AMF inoculation was very similar to that obtained in light peat alone.
These results show that the undesirable negative effect of AMF, often observed after inoculation, can at least partly be overcome by using decomposed peats and potting mixes of peat and mineral components, in particular clay.
Publication
Authors
M. Vestberg, S. Kukkonen
Keywords
arbuscular mycorrhizal fungi, Carex Bryales peat, growing medium, potting mix, Sphagnum peat
Online Articles (56)