Principles of Plant Genetics and Breeding

358 CHAPTER 19
Product concept
Understanding the needs of the customer, in this case the wheat growers, and then determining the technical criteria to meet
those needs, are critical components in developing the product concept. In focus group sessions conducted in 2000, spring wheat
growers identified numerous challenges with their current weed control options. These challenges included:
1 Incomplete control of many tough weeds.
2 Annual variability in product performance.
3 Crop damage/setback caused by herbicides.
4 The need for multiple products to broaden the spectrum of control.
5 Significant price variability based on the quantity and type of weeds.
The product concept for Roundup Ready® wheat is complete, dependable, cost-effective control of all weeds, often with only
one herbicide application. Four years of field trials indicate that a single 26 oz/acre application of Roundup UltraMax® over the
top of Roundup Ready® spring wheat provides 95–100% control of nearly all broadleaf and grassy weeds (Figure 2). Before a project
is initiated, a market assessment is completed to understand the commercial potential for that trait/crop combination. If the
results of that study are promising, then the project is initiated.
The development team
Because there are so many aspects to bringing a new product to commercialization, a wide diversity of expertise is needed
amongst team members. Early-stage development teams usually combine expertise in molecular biology, transformation, genetics,
plant breeding, agronomy, and regulatory science. Bench scientists who have expertise in one of the team areas often lead
early-stage teams. For instance, the early-stage Roundup Ready® wheat technical team was led by a molecular biologist. Midstage
development teams evolve to incorporate additional expertise in regulatory affairs, seed production, industry affairs, public
affairs, government affairs, and commercial development. People who specialize in managing product development typically
lead these teams. Late-stage development teams evolve again – phasing out the expertise in molecular biology, transformation,
and genetics, while adding expertise in marketing. Someone from the commercial arena usually leads these teams.
Transformation
To be commercially successful, a crop not only has to be transformed, but the process has to be amenable to making hundreds
of transgenic plants. Monsanto developed a process to transform wheat, using the trait of interest – glyphosate tolerance – as
the selectable marker. The transformation
method also must result in transgenic
plants that are “clean” events – meaning
that the DNA insertion is registerable
with many regulatory bodies around the
world. It has been our experience that
Agrobacterium transformation results in
more useful events than does particle gun
transformation (Hu et al. 2003).
Untreated Control
The gene and its expression in the
Roundup Ready Wheat
plant
Figure 2 Product concept demonstration: control of broadleaf and grassy
weeds.
In Roundup Ready® crops, the principal
gene that has been used is the CP4
EPSPS gene, which was isolated from
Agrobacterium. This is the gene present in
Roundup Ready® wheat. The expression
of this gene allows the plant to continue to
produce aromatic amino acids after the
application of one of the Roundup® family
of herbicides. The challenge is enabling
the gene to be expressed in the right tissues
at the right time. The promoters control
expression. Some promoters, like the
cauliflower mosaic virus-enhanced 35S