Description
Maize,
or corn, is the world’s biggest and most important crop, although its uses
aren’t limited to human food; it’s an important industrial crop, too. OECD
figures put global maize production at 1 billion tonnes in 2016.
Wheat,
barley, rye and triticale are other commercially important cereals susceptible
to slug damage.
Susceptibility to Slug Damage
Slug
damage is especially an issue in low, or no-tillage situations, where soil
trash provides both shelter and feeding material.
Loss
of yield potential from defoliation can be up to 10%.
Slug
damage is generally worse if seedlings emerge at times when slug feeding is
intense. For example, warm winters and late plantings may result in an
increased slug population.
Species of Concern
The grey field slug, Deroceras reticulatum,
is the most common pest of maize crops although both the keeled and
round-backed slugs also cause damage.
Symptoms of Attack
Slugs typically attack young seedlings, scraping
strips in the leaves to leave a classic ‘window pane’ effect. The attacks may
worsen to the degree of leaf stripping, followed by plant loss.
Solution
There
is no established threshold level for slugs in maize, but monitoring for slugs
and eggs – particularly is crop residue and trash is present in the field – can
help establish a benchmark population (usually per plant), which can then be
observed over time. An increase in the population will assist with
decision-making for the application of pellets.
An
even distribution is important to ensure slugs come into contact with pellets
as soon as possible. Calibrate your equipment carefully.
Cultural Control methods can help reduce the need for slug
pellets.
AXCELA® is approved for use on maize in New
Zealand.