SUPPRESSING PYTHIUM ULTIMUM INDUCED DAMPING – OFF IN CABBAGE SEEDLINGS BY BIOSTIMULATION WITH PROPRIETARY LIQUID SEAWEED EXTRACTS

Fewer cabbage (Brassica oleracea var. capitata) seedlings were infected with Pythium ultimum, the causal agent of damping – off disease when the peat based potting compost was treated with liquid seaweed extract (LSE) in advance of inoculation with the pathogen.
The most effective treatment was the application of 1 % LSE applied in advance of inoculation with P. ultimum. The effects of LSE are believed to be due to a stimulation of populations of microbes that are antagonistic to P. ultimum thereby reducing the pathogenic inoculum potential (sensu Garrett). Liquid seaweed extract is considered to be a biostimulant in these events.
The nature of biostimulants and their potential for inclusion in the biological control aspects of Integrated Crop Management (ICM) strategies is discussed and evaluated.
Formulating ICM with a large range of components enhances its effectiveness making it less prone to erosion following the development of tolerance in pathogen populations.
Furthermore, biostimulants are generally natural products and hence are unlikely to result in adverse environmental effects.

XXVI International Horticultural Congress: Managing Soil-Borne Pathogens: A Sound Rhizosphere to Improve Productivity in Intensive Horticultural Systems

G.R. Dixon, U.F. Walsh

Pythium ultimum, damping – off, liquid seaweed extract, Integrated Crop Management, ICM, cabbage, Brassica oleracea, biological control, rhizosphere, antagonism, suppressive soils

https://doi.org/10.17660/ActaHortic.2004.635.13