Agriculture Reference
In-Depth Information
Studies. on. gene. low. and. impact. on. lora. and. fauna. for. a. new. transgenic. crop.
are. compiled. and. submitted. as. a. petition. for. deregulation. by. the. USDA.. In. addi-
tion. to. the. detailed. molecular. and. ecological. studies. required. by. the. USDA,. the.
Environmental.Protection.Agency.(EPA).requires.registration.of.what.it.deines.as.
Plant.Incorporated.Protectants.(PIP).
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.A.PIP.is.a.“pesticidal.substance.that.is.pro-
duced.in.a.living.plant.and.the.genetic.material.necessary.for.the.production.of.the.
substance,.where.the.substance.is.intended.for.use.in.the.living.plant.”.This.deinition.
does.not.include.genes.moved.into.a.variety.through.conventional.breeding.or.cell.
culture. techniques,. but. only.covers. genes. transferred. to.a.variety.by. genetic. engi-
neering..It.also.does.not.cover.pesticidal.genes.transferred.from.closely.related.spe-
cies..To.conduct.the.necessary.ield.experiment.prior.to.iling.for.EPA.approval.and.
registration.of.a.PIP.containing.variety,.a.developer.must.obtain.an.Experimental.Use.
Permit.(EUP).in.addition.to.the.USDA-APHIS.permit..Final.registration.requires.a.
commitment.to.post-registration.monitoring.and.stewardship..For.commodity.crops.
registered.to-date,.this.has.included.preparation.of.an.Insect.Resistance.Management.
Plan.(IRM).including.the.use.of.non-transgenic.refuges.to.reduce.the.potential.for.
insects.resistant.to.the.PIP..There.are.currently.no.examples.of.EPA.approved.PIPs.in.
ornamental.crops,.and.it.is.unclear.what.refuge.and.stewardship.requirements.would.
be.required.for.transgenic.ornamentals..Natural.refuges.would.exist.in.all.other.non-
transgenic.plants.in.the.surrounding.landscape..Furthermore,.EPA.PIP.registration.
for.commodity.crops. is.valid.for.about.3-5. years.. This.would.not.be.practical.for.
plants.used.in.a.garden.or.landscape.environment..Would.the.consumer.be.expected.
to.discard.his/her.aphid-resistant.rose.bush.after.5.years?
Perhaps.one.of.the.most.signiicant.differences.in.design.of.transgenic.and.non-
transgenic.ield.tests.is.that.conventional.ield.tests.and.trials.are.conducted.in.par-
allel. on. hundreds. of. candidate. varieties.. Commercial. ield-tests. typically. contain.
several.hundred.distinct.varieties..Each.variety.may.differ.in.one.or.more.traits..It.is.
fairly.common.for.a.developer.to.include.lines.selected.from.a.broad.array.of.parents.
that. exhibit. wide. variation. in. color. range,. habit,. and. disease. resistance. traits. in. a.
single.ield-test.location..In.contrast,.for.transgenic.varieties,.gene.low.studies.and.
insect. impact. population. studies. are. typically. conducted. on. one. variety. at. a. time..
In.some.cases,.multiple.lines.each.carrying.a.distinct.gene.insertion.event.may.be.
characterized.in.parallel..This.greatly.increases.the.cost.per.variety.for.transgenic.
varieties.compared.to.non-transgenic.varieties.
Many. of. the. genes. proposed. for. use. in. ornamentals. are. derived. from. plants..
These.include.genes.involved.in.pigment.biosynthesis.and.genes.conferring.altered.
plant.habit.
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.The.consequences.of.gene.low.between.related.species.of.ornamentals.
will. probably. depend. on. the. exact. transgene. in. question.. In. a. hypothetical. case,.
would. a. gene. derived. from. Arabidopsis. and. conferring. dwarf. phenotype
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. confer.
any.selective.advantage.if.transferred.from.a.transgenic.hybrid.rose.to.a.multilora.
rose?. Would. it. make. a. difference. if. the. gene. were. derived. from. rose. instead. of.
Arabidopsis?. Indeed. in. 2007,. the. USDA. proposed. a. tiered. regulatory. structure. in.
which. certain. low-risk. transgenics. are. regulated. less. stringently. than. higher. risk.
transgenics.
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. In. this. context,. technical. reinements. may.help. lower. the. regulatory.
cost.and.burden..The.development.of.native.selectable.markers,
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.positive.selection.
systems,
25,26
. marker. removal. systems,
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. and. marker-free. systems. is. one. approach..
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