Back A. Borgen
Department of Agricultural Sciences, The Royal Veterinary and Agricultural University, Agrovej, Taastrup, Denmark
Full Paper (PDF File: 49KB)
Abstract
Common bunt is one of the most important diseases in winter wheat, and
one of the most intensively pesticide treated diseases in regions where
this pathogen occurs. When pesticides are not used in seed propagation,
i. e. in organic agriculture, the disease is normally a serious problem.
EM1 is a product used in Kyusei Nature Farming, containing a bunch of different
microorganisms against various fungal plant diseases. In order to develop
methods to diminish pesticide use, and to improve organic agriculture,
the potential of EM to regulate this pathogen was investigated. In 1996
seeds contaminated with teleutospores of Tilletia tritici were treated with two levels of EM1, two levels of acetic acid and two
levels of milk powder. A combination of EM1 and milk powder were tested
as well.
EM1 had a significant effect on disease rate (87.6% reduction) when applied
in high dosages (150ml/kg seed), but in this dose germination vigour and
field emergence were also negatively affected. The use of the same dose
of autoclaved EM1 had almost the same effect on disease rate and germination
vigour. This might indicate, that the causative agent in the EMI product
is not the effective microorganisms themselves, but the metabolites of
the organisms, most probably lactic acid. Using acetic acid (1.22M, 30ml/kg)
it was possible to get a better control of the pathogen with no significant
harm to germination. Based on these trials it can be concluded, that EM1
is not an optimal control agent against common bunt. However the use of
EM1 did reduce the disease rate, and this can therefore be a positive side-effect
if EM1 is used as a seed treatment for other reasons.