South Perth, Western Australia
March 31, 2006
Correctly
managed application of fungicides and sourcing seed with low
infection levels will greatly reduce the incidence of smut in
barley crops this season, according to
Department of Agriculture
plant pathologist Kith Jayasena.
Dr Jayasena
said high levels of loose smut had been reported in some Baudin
barley seed planted across the state over the past two seasons.
“Department
trials of fungicides containing the active ingredients of
triadimenol, triticonazole and tebuconazole have proved
effective in reducing loose smut incidence by 60 to100 per
cent,” he said.
“However,
trials using difenoconazole in fungicides applied in-furrow were
not effective at reducing smut.”
Dr Jayasena
said it was also critical that growers ensured, when treating
seed, that all seeds were covered with fungicide, to achieve
optimum protection and control.
He said the
other important factor in controlling smut infection was
sourcing seed from areas with the lowest possible exposure.
“There is a
direct relationship between percentage of infected crop and
yield,” he said.
“For example a
crop with a 10 per cent infection would result in a 10 per cent
yield reduction. Therefore a crop with a yield of 2.5t/ha and
farm gate price of $156/t would result in a reduction of $39/ha
on returns.
“Seed with
greater than five per cent infection should not be used. Seed
with less than five per cent infection should be treated each
year with a fungicide effective against smuts.”
More
information on controlling smut in barley crops is available
from Farmnote 10/2004 Cereal seed dressings and in-furrow
fungicides 2004-2005 on the
Department of Agriculture
website. |