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It's in the bag

You first saw it in 2010
when Monsanto and Dow AgroSciences unveiled SmartStax. This was – and still is
– the king of trait stacks. It has six above- and below-ground insect traits
and two herbicide-tolerant traits.

Another perk SmartStax
brought was a 5% structured refuge, a cut below the standard structured 20%
Corn Belt refuge for insect stacked hybrids. 

That same year, Pioneer
Hi-Bred notched refuge changes upward with a limited offering of Optimum
AcreMax 1 (OAM 1). The EPA approved this first refuge-in-a-bag (RIB) product in


This was just the start,
though. By 2012, Pioneer plans to launch a more comprehensive refuge product,
Optimum AcreMax 2 (OAM 2). Monsanto and Dow AgroSciences plan to market their
SmartStax RIB products in 2012. Meanwhile, Syngenta Seeds has RIB products on
tap for 2012 and 2014. These dates hinge on federal approval.

A Welcome Addition

Farmers will likely welcome
RIB as much as baseball fans welcome cold beer during a sweltering July
doubleheader. RIB nixes the need for a separate structured refuge because it’s
already contained in the existing seed mix. All you need to do is add seed to
the planter and go.

“Farmers lose time when they
have to fill their planters with (refuge) seed and lay out the appropriate
separate refuge,” says Robb Fraley, chief technology officer for Monsanto. “The
convenience refuge-in-a bag offers is a huge benefit.”

Then there’s the yield gap.
Differences between refuge and Bt corn can be mind-boggling, particularly in
corn plagued by corn rootworm in stressful years. In a 2006 University of
Illinois (U of I) study, a 100-bushel-per-acre difference resulted between
traited and untraited corn. Although that’s an exception, stressful years bring
out sizable yield differences.

RIB also pleases regulators.
“Recent surveys shows (refuge) compliance has been slipping in recent years,
says Mike Gray, U of I Extension entomologist. “The EPA likes this approach
because it ensures compliance.”

These factors lead Gray to
expect lower-percentage refuges contained in a bag to predominate hybrid
offerings by 2015 and 2016. “When we look ahead, we will see massive insect
suppression for lots of corn insects,” he says.

Any downsides? Well, you’ll
probably pay more. Since 1999, prices paid for seed corn rose 146%, with 64% of
that rise occurring during 2007-2009, according to USDA. Although that’s
stalled this year, new innovations like RIB will generally increase prices,
Gray says.

Pyramid Stacks 

EPA mandated that farmers
plant a 20% refuge for Bt insect-resistant hybrids to prevent resistant insects
from surfacing. Despite this inconvenience, farmers quickly adopted this
technology and its refuge mandate. By 2010, farmers planted 63% of U.S. corn acres
to Bt insect-resistant hybrids.

That’s because Bt hybrids
worked. Although the 100-bushel yield gap is a rarity, yield differences of 20
to 50 bushels per acre between Bt and non-Bt corn have often occurred. This
caused some farmers to nix refuges.

A Center For Science In The
Public Interest report found refuge compliance exceeded 90% from 2003 to 2005.
By 2008, though, roughly 25% of producers who planted Bt corn were out of

On-farm industry audits
revealed greater levels of compliance; however, trends were similar, notes

“With refuges, it’s a hard
choice to drop yields over 20% of your fields,” says Gordon Wassenaar, a
Prairie City, Iowa, farmer.

This concern is decreasing,
though, due to Bt pyramided hybrids. They differ from the Bt stacked hybrids
you’ve planted for the past several years. These stacks can contain multiple
traits, but only one Bt protein is targeted at a specific pest.

Pyramided Bt hybrids differ.
They aim several Bt toxins differing in action modes at a single insect class.
Two Cry proteins may aim at ECB, while two others target corn rootworm.

New pyramided hybrids
include Dow AgroScience’s SmartStax, Monsanto’s Genuity SmartStax, Genuity VT
Double and Triple Pro, and Syngenta’s Agrisure Viptera 3111.

Pyramided Bt products have
key benefits. “When you stack multiple (rootworm) modes of action together, the
rootworm would have to mutate at two different sites on the genome to survive,”
says Dirk Benson, head of trait product management for Syngenta Seeds.

Since this is difficult,
farmers double the odds of control and also enhance resistance management, he

Multiple modes of action
mimic a baseball pitcher with a mix of pitches. Batters may figure out how to
hit a pitcher who throws continuous fastballs. Eventually, hitters figure out
the pitcher and wallop the pitches. Not so if a pitcher laces his fastballs
with curveballs and sliders. Multiple types of pitches keep hitters off

Multiple Bt proteins mimic a
baseball pitcher’s mix. Within each insect population is a biotype that
eventually adjusts to a continual barrage of Bt toxins. Mixing in several Bt
toxins, though, throws it off balance and forestalls resistance.

It’s this technology that
prompted companies offering pyramided products to request a 5% refuge from EPA,
says Gray.



So far, , there’s just one
RIB on the market: Pioneer Hi-Bred’s OAM 1. It blends 90% Herculex Xtra corn
with 10% Herculex 1. Herculex Xtra protects against both above- and
below-ground pests, while Herculex 1 protects against just above-ground pests
(no rootworm) and serves as the integrated rootworm refuge.

“When used with Optimum
AcreMax RW as a corn borer refuge, growers can get integrated corn rootworm
technology across 100% of their acres,” says Bill Belzer, Pioneer senior corn
marketing manager for North America.

Competitors criticize the
AcreMax strategy, particularly the first-generation strategy that splits out a
separate ECB block refuge. Monsanto has called AcreMax 1 “misleading” in its

“When we talk about
refuge-in-a-bag, we are talking about a single, individual bag that will work
in a planter as a single-bag system,” says Monsanto’s Fraley. “Other companies
are talking about a special refuge for the rootworm component, where 10% of the
plants are exposed and they still need a 20% refuge for a caterpillar
(including ECB) component. There are two-bag systems they call one-bag systems,
but they are instead managing multiple bags, multiple inventories.”

This will change, though,
when OAM 2 hits the market in 2012, pending regulatory approval, says Pioneer’s
Belzer. This will nix the need for a separate refuge by combining two ECB modes
of action via Herculex Xtra and Yield Gard Corn Borer with a corn rootworm

Refuge Percentages


Concerns also are being
raised regarding Optimum AcreMax’s 10% refuge component. Surveys at U of I Corn
and Soybean Classics at several Illinois locations showed roughly 90% of those
interested in planting RIB would use a seed blend containing non-Bt seed in the
2% to 5% range. That percentage, though, dipped to around 53% when the non-Bt
seed fell within the 6% to 10% range, says Gray.

“We believe 5% is the right
amount,” says Fraley. That’s the current refuge of SmartStax hybrids under the
separate refuge, and one Monsanto anticipates will be approved for its RIB
product, Genuity SmartStax RIB Complete. Syngenta Seeds also is aiming at a 5%
refuge with its Agrisure E-Z Refuge products, as is Dow AgroSciences with its
SmartStax Refuge Advanced product.

“Those are quite a few
unprotected plants (in refuges exceeding 5%) in a field,” says Grant Ozipko,
Syngenta Seeds traits marketing manager. “If you have significant pest
pressure, there is a risk that you can cause problems from the harvest
perspective or the amount of damaged corn. From growers’ perspectives, it
reduces confidence.”

EPA also registered
resistance management concerns It has stated the proposed 90-10 seed blend’s
45% less durable on a comparative basis than a 20% block refuge now required
for single-trait corn rootworm traits. It calculated the 90-10 mix to develop
resistance in 11.3 years, compared to 20.2 years for the 20% separate block
refuge. Unlike pyramided products, OAM doesn’t offer multiple modes of action
aimed at one type of insect, Gray notes.


However, Pioneer Hi-Bred
officials say its company trials show the technology is sound from both an
insect-control and resistance-management standpoint.

“In our model that was
vetted with academic experts and entomologists, we found AcreMax would be as
durable – and in many cases more durable – as a 20% traditional block refuge,”
says Pioneer Hi-Bred’s Belzer. “We are respective of EPA’s model. But the one
element to take into larger consideration is that we obtained registration. As we
and EPA looked at all the factors involved, there was a compelling case made to
register the product.

“EPA is pretty conservative
for new products like this,” continues Belzer. “This is an industry first. They
(EPA) felt it was a compelling product to put in the marketplace from a
durability standpoint. We have two seasons to sell the product before we
reregister. In 2010 trials, the 90-10 OAM 1 product produced the same yield
performance as a pure stand of Herculex Xtra.”

Product Lineup

Pioneer Hi-Bred

Optimum AcreMax (OAM) 1 and

Refuge Amount:10%

What it is: OAM 1 is a mix
of Herculex Xtra and the refuge component Herculex 1. Its corn rootworm refuge
is blended within the bag. A separate 20% structure refuge is required for European
Corn Borer (ECB) within ½ mile.

OAM 2 will contain two ECB
modes of action and a corn rootworm control in one bag.

Status: Federal regulators
approved OAM 1 in 2010. OAM 2 is slated for 2012, pending federal approval.

Syngenta Seeds

Agrisure E-Z Refuge

Proposed Refuge: 5%

What it is: Agrisure 3122
E-Z Refuge offers corn rootworm and ECB control. Agrisure Viptera 3223 E-Z
Refuge will contain Syngenta’s Vip3A action mode for lepidoptoran (ECB) and a
new rootworm action mode. Agrisure 3220 contains the Vip3A mode of action.

Status: Pending federal
approval, the Agrisure 3122 and 3220 RIB products are slated for 2012, and the
Agrisure 3222 RIB product in 2014.


Genuity SmartStax RIB

Proposed Refuge: 5%

What it is: SmartStax
contains six insect-resistant traits with multiple modes of action and two
herbicide-tolerant traits.

Status: Slated for market in
2012, pending federal approval.

Dow AgroSciences

SmartStax Refuge Advanced

Proposed Refuge: 5%

What it is: SmartStax
contains six insect-resistant traits with multiple action modes and two
herbicide-tolerant traits.

Status: Slated for market in
2012, pending federal approval. 

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