Healthy Soil - Healthy Plants? F2
University of Kassel, Department of Agriculture, International Rural Development and Ecological Environmental Protection, Division of EcologicalAgriculture, Nordbahnhofstrasse 1a, D-37213 Witzenhausen
|Ideas regarding plant health in the field of
ecological agriculture are based on the assumption that resistance of plants to diseases
and pests can be influenced up to certain limits by controlling environmental conditions
and vegetation factors. The main goal in this matter is not the elimination of pests. The
aim of ecological agriculture is rather more the exploitation of all measures available to
a farm using self-regulating mechanisms as far as possible. The example of the
interactions between soil conservation and plant health should make this clear.
A healthy soil is always related to an intact soil biota considered to befundamental with regard to soil fertility. Among others, this is stimulated by the application of farmyard manure or compost fertilization, which subsequently causes frequent appearance of biological controlling meachanisms - e.g. to root pathogens -, due to an intense microbial soilactivity. The increasing diversity in the composition of soil biotic communities reduces the ability of potential pathogens in terms of spreading and infection. Ecological niches taken by corresponding antagonists is another example for an active mechanism in suppression of pathogens. Above all compost application intensifies this antiphytopathogenic potential in soils by stimulating microorganisms and soil animals.
The improvement of aggregate stability, the higher water infiltration rate and hydraulic conductivity, the increased cation exchange capacity and the reduction of soil erosion are further important aspects of soil fertility influencing plant health in a positive manner. These factors provide a stress-free environment for plant growth, thus these plants can better resist pests and diseases.