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Why
is the license expiring? The EPA has played an active role in managing
resistance to Bollgard™ from its introduction. Bollgard™ cotton
contains a gene from the bacteria Bacillus thuringiensis (Bt) that
produces an insecticidal protein which is toxic to various caterpillar
pests. This protein has a single mode of action. When the original
license was approved in 1995, EPA expected resistance to develop in
tobacco budworm within ten years. Farmers were required to plant part of
their cotton crop each year in refuge acres. Approval of the license was
contingent on the development of a system with two genes and two modes
of action to replace Bollgard™. To date, the refuge requirements
mandated by EPA have worked and resistance in tobacco budworm has not
developed. This has resulted in a series of extensions of the license,
the latest of which expires in 2009, 14 years after the original
approval.
Germplasm
and Technology Choices
Following
expiration of the license in 2009, cotton growers will have several
technology choices. As a result of the overlap in old and new
technologies, we have the advantage of field experience with these
choices. They have been validated in on-farm use over the past several
years. Monsanto will offer Bollgard II™ and Roundup Ready Flex™.
Bollgard II™ contains the Bollgard™ gene plus an additional Bt
gene with a different mode of action. Roundup Ready Flex™ allows
season-long, over-the-top applications of glyphosate herbicide. Dow
AgroSciences will offer Widestrike™, another two Bt gene
system. Both Bollgard II™ and Widestrike™ have improved efficacy
against several worm pests, including cotton bollworm and fall armyworm
and do not require the planting of refuge acres. Bayer CropScience will
offer Liberty Link™, which allows over-the-top applications of Ignite™
herbicide.
Growers
will face a different situation in 2010 than in 1996. In 1996, cotton
farmers adopted a new technology and a new variety. The focus was on the
technology. Today, growers are familiar with available technologies and
the focus is on germplasm. Seed companies recognize this and are pouring
resources into the production of new varieties with new technology that
outperform established BG/RR varieties. The resources are considerable:
with the acquisition of Stoneville by Bayer CropScience, FiberMax and
Stoneville now have nine breeding programs in the U.S.; Delta & Pine
Land, which was acquired by Monsanto last summer, has eight breeding
programs in the U.S.; and Phytogen Seed Company, which is owned by Dow
AgroSciences, has two breeding programs. Monsanto also owns Cotton
States, which draws from public and private breeding programs and
licenses varieties out to companies such as Croplan Genetics.
In
general, the cotton varieties which have entered the market since
Roundup Ready Flex™ was approved for sale in 2006 have not yet
performed with established BG/RR varieties. The reason for this can be
found in the interaction between Monsanto and various seed companies as
Monsanto began to field test Roundup Ready Flex™ technology. Early in
the field testing process, Monsanto allowed seed companies to submit
germplasm for placement of the new technologies. This germplasm
eventually became the first Bollgard/Roundup Ready Flex™ varieties
that came to market. After several years of testing and selection of the
final event offered for sale, Monsanto turned over the event to seed
companies for variety development. Seed companies have been working
furiously since that point. The bottom line for cotton growers in
Alabama is we are on the verge of seeing great new cotton varieties to
go with the new technologies.
REFERENCES:
Cotton Insect Losses,
Beltwide Cotton Conference Proceedings, 1995-2007.
Brad
Meyer is an agronomist for Agri-AFC. Contact him at
bradm@agri-afc.com. |