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4-Patents: Monsanto awarded transgenic refuge patent

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                                  PART I
-------------------------------- GENET-news --------------------------------

TITLE:  Monsanto Awarded Transgenic Refuge Patent
DATE:   April 2003

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Monsanto Awarded Transgenic Refuge Patent

Monsanto has been awarded US Patent 6,551,962 covering a Method for
deploying a transgenic refuge. The patent, invented by Jay C. Pershing,
Eric S. Sachs and Ernest F. Sanders covers a method to protect corn
against feeding damage by one or more pests which includes the treatment
of corn seed having a transgenic event that is targeted against at least
one of the pests with a pesticide in an amount that is effective against
the same or another of the one or more pests. Seeds having such
protection are also disclosed, as well as a means for deploying a non-
transgenic refuge crop into a field of transgenic crops.

"The present invention is also directed to a method for deploying a non-
transgenic refuge crop into a field of recombinant pest resistant crops,
effectively reducing the labour, costs, and management required to deploy
a refuge into a field adjacent to, along side of, or within a close
proximity to a field of recombinant crops," say the patent's authors.
"Such a refuge could be either a mixture of recombinant pest resistant
seeds and non-recombinant seeds each treated with a seed coating
comprising a chemical insecticide, nematicide, herbicide, or fungicide
alone or in combination, each present in an amount effective for reducing
or eliminating pest infestation within a diffusible zone around the site
into which the roots of the germinated or sprouted seed would introgress,
and through which the root system of the germinated or sprouted seed
would grow without inhibition or delay in growth and development to said
root system as a result of the chemical insecticide, nematicide,
herbicide, or fungicide composition or coating."

The inventors says the approach offers improved protection of plants from
feeding damage by pests; reduces the required application rate of
conventional chemical pesticides; also the provision of such a method
that limits the number of separate field operations that were required
for crop planting and cultivation; and also the provision of a method for
deploying a non-transgenic refuge crop into a field of transgenic crops.

The patent text notes that one concern about the commercial release of
transgenic maize for control of corn rootworm is the evolution of
resistance by the rootworms. One means for managing the development of
resistance is to require that producers and growers plant a refuge to
maintain resistant alleles at a low frequency. This disclosure
illustrates a seed mix refuge option. The inventors present data that
show a seed mix maintained root damage levels below the economically
damaging levels and produced similar numbers of adult beetles. "The
combination of a seed treatment along with the deployment of refuge seed
in a mix of transgenic seeds is therefore a useful strategy for
prolonging the onset of resistance to either the seed treatment or to the
recombinant insect inhibitory trait contained within the plant tissue."

Monsanto Agricultural Company, 700 Chesterfield Village Pkwy, St. Louis,
MO , 63198 , United States 
Tel: +1 (314) 694-1000 

                                  PART II
-------------------------------- GENET-news --------------------------------

TITLE:  Pink seed corn might kill costly rootworms
SOURCE: Argus Leader, USA, by Mark Steil (Minnesota Public Radio)
DATE:   May 4, 2003

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Pink seed corn might kill costly rootworms

LAKEFIELD, Minn. - Seed corn is becoming so high-tech it doesn't even
look like corn. It's pink. The new color is from a chemical shield
encapsulating the golden kernels.

Keith Buresch said the coating protects the seed from insects and disease
during its first weeks in the ground. "The seed is the biggest decision a
farmer makes," Buresch said.

Buresch runs a seed supply business on his farm near Lakefield, in
southwest Minnesota. He said area farmers are interested in the new
Monsanto corn. It manufactures a protein deadly to corn rootworms. He
said rootworms cause $1 billion in damage each year in the United States.

"I would say in my trade area, it's our biggest problem in corn
production," Buresch said. That's because the rootworm has shown an
unnerving ability to overcome farmers' best efforts to beat it. The
rootworm has built up resistance to many chemical treatments. Even more
impressive are the lifestyle changes the insect has made.

One of the most effective tools farmers have is to rotate their crops.
Most plant corn one year and soybeans the next in the same field.
Rootworms can't eat soybean plants, so they die soon after hatching. But
entomologist Wade French, who has studied the rootworm for years, said
the pest adapted to the strategy.

"Some of the eggs would undergo two-year over-wintering, or what's called
a diapause stage in their life," French said. "And then they would emerge
when corn was planted the following year. They would, of course, survive."

Other rootworms found a different way to adapt to crop rotation. When
it's time to lay eggs, the adult rootworm beetles fly from the corn
fields where they hatched to nearby soybean fields. The eggs spend the
winter there before hatching the next spring, just in time for the larva
to feed on corn roots.

French said it's like an arms race. When the insect catches on to the
latest weapon, it's time for a new one. So what are the chances the
rootworm will adapt to genetically modified corn?

"If there's an insect that can do it, it (rootworms) probably will,"
French said.

That's because genetically modified corn doesn't kill every pest. French
said the rule of thumb is that one rootworm beetle in 1,000 have a
natural immunity to the inbred toxin. To prevent the population of immune
rootworms from growing, farmers must take certain steps. Twenty percent
of their corn must be an "old-fashioned" variety - not genetically
modified. French said it provides a refuge for the corn rootworm.

"The idea of the refuge is that any insects that evolve resistance to the
toxin, will have other insects to mate with that are susceptible to the
toxin," French said. The offspring of that pairing will also be
susceptible to the toxin in genetically modified corn.

Farmer Keith Buresch said besides killing rootworms, the new corn has
another benefit. Since it produces its own toxin, farmers don't have to
kill the pests by spraying insecticides.

"Insecticides are just poison. Probably no farmer likes to work with
insecticide," Buresch said. "If you've ever had it go up your nose or
down your throat, it's not fun."

For some farmers, reducing insecticide use is the most important reason
for planting genetically modified crops. But some farmers still oppose
using the seed. They worry the crops will kill beneficial insects, or
that the pollen will drift and contaminate non-genetically modified crops.

But so far, the concerns haven't significantly slowed interest in the new
seeds. Half the corn and three-quarters of the soybeans planted this year
in Minnesota are expected to be a genetically modified variety.