EFFECTS OF HUMIC ACIDS AND THREE BIO-DYNAMIC PREPARATIONS ON THEGROWTH OF WHEAT SEEDLINGS
G Deffune1 and AM Scofield
Allelopathic effects are biochemical interactions of both inhibitory and stimulatory nature between plants and microorganisms. Both opposites seem to be separated by quite a thin line - most organic compounds that are inhibitors at some concentrations are stimulators to the same processes at higherdilutions (Rice 1984). The mode of action of plant growth hormones such as indole-3yl-acetic acid (IAA) illustrates this phenomenon: while 10-11 M is the optimum level for roots, concentrations above 10-6 M strongly inhibit root growth (Audus 1972). In this context humus and humic acids (HA) have also been the subject of several studies related to plant growth.Bio-dynamic farming is the oldest movement for sustainable agriculture. It differs from the other movements basically by the use of the bio-dynamic (BD) preparations: mineral, plant or animal extracts, usually fermented and applied in small proportions to organic manures, the soil or directly on plants, after dilution or stirring procedures called dynamizations.
Research publications concerning biodynamics