Soybean pests
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Bugs:
Of all bugs that have thepotential to infest soybean crops, the ones that suck the
pods are themost destructive. These insectsmay belong to several species, which occur to-
gether or alone. Thebrown-bug is themost feared, due to its abundanceandpresence in the
entireCountry. By attacking thepods, the kernels have theirweight reduced, besides paving
the way for microorganisms that jeopardize the quality of the crop. When the pods are at-
tacked at the time the kernels are beginning to develop, a pod abortion processmight start.
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Worms:
There is abiggroupofworms capableof infesting soybeancrops. The soybean
worm and soybean looper are the most common and most destructive species. They feed
on the leaves and cause defoliation, reducing the photosynthetic power of the plant. When
this defoliation is higher than 30%during the vegetative periodof the growing stage, or 15%
higher during the reproductive period of the growing stage, the photosynthetic capacity is
reduced to the point that the plant is deprived of its nutrients, jeopardizing its development
and, consequently, its productivity.
tions, has achieved positive results that il-
lustrate the importance of this tool.
The initiative, conducted for more than
three crops in a row inmedium-sized fields,
sets forth the application of the IPM Soy-
bean and other best agricultural practic-
es, recommended by extension agents.
The results demonstrate, among other as-
pects, that delays in the application of in-
secticides preserve the natural enemies of
the pests, like predators, parasites and en-
tomopathogens, reducing theneed for gen-
eral controls and, as a result, preserving the
efficiency and longevity of the product.
According to the scientist, the Inte-
grated Soybean Pest Management pro-
claims that the crop, even when it comes
to modern cultivars, has tolerance to pest
outbreaks, before having its productivi-
ty threatened. Therefore, infestations of
pest-insects are tolerable up to a certain
level, without any risk for economic re-
ductions of the productivity rates. “The
application of insecticides is only justifi-
able when the population of pests is equal
or superior to the levels of action (NA),
that represent the correct moment for
the control to be carried out”, he explains.
Adeney also refers to the importance of
identifying the type of pest before the use
of the insecticide, especially when it comes
to controlling worms. “A product or even a
dose of a certain product could be different
for each prevailing type of pest”, he says.
The choice for the best alternative and cor-
rect dosage to be used, according to the re-
searcher, can only be carried out when the
predominant species in the field is known,
whichdepends on the sampling procedure.
“It is one of the requisites to ensure suc-
cessful management, which will implicate
in maintaining the productivity rates and
cost reductions”, he concludes.
