Impact And Management Of Diseases And Mycotoxins In Corn
LONOKE, ARK.
Management of foliar diseases and mycotoxins
in corn has become an important
factor in production with increased
acreage and expansion of the current planting
window in Arkansas.
For foliar disease, fungicides are often utilized
to protect the crop. One of the major limiting factors
for this control strategy is a lack of information
for the proper usage and timing of
fungicide applications, especially in later planted
corn. Also, limited information is available regarding
resistance to southern rust and other
important corn diseases on currently planted
hybrids.
Beyond foliar diseases, aflatoxin contamination
remains the most important disease-related
problem in Arkansas corn production. Once
contaminated, there is no easy or practical answer
for dealing with the grain, from a farmer
standpoint. So preventing aflatoxin contamination
is key. Aflatoxin can reduce the value of
corn from 50 – 100%, depending on US corn
supply current market conditions. In an epidemic
year, like 1998, it affected up to 50% of
Arkansas’ corn acreage costing our growers an
estimated $15,000,000 in direct losses. One potential
option for growers in managing aflatoxin
development may be usage of the newly available
microbial antifungal crop protection product
Afla-Guard. Afla-Guard contains a
naturally-occurring, non-toxic fungus that reduces
the development of the fungi that produce
aflatoxin in grains, nuts and oil seeds through
competition. Although Afla-Guard is registered
for use in corn, little research has been conducted
in Arkansas regarding the effectiveness
of non-toxic fungus to reduce the aflatoxin development
in our environment, optimum application
methods, timing of application, and
economical benefit or return of this bio-control
agent.
Research efforts in Arkansas have concentrated
on the most effective usage of fungicides
and bio-control products to lessen the impact of
major foliar diseases and mycotoxins. However,
to control corn diseases and mycotoxins effectively
these products need to be utilized in combination
with other management strategies
including resistance, hybrid adaptability, planting
date, proper fertilization, and water management.
Results of current fungicide and
Afla-Guard trials along with other management
strategies will be presented. Δ
DR. W. SCOTT MONFORT: Associate Professor/
Ext. Plant Pathologist, University of Arkansas