Transgenic Fruit Crops in Europe - Transgenic Horticultural Crops: Challenges and Opportunities - page 137

S trawberry
Eight.summary.notiications.can.be.found.for.GM.strawberries..Field.trials.with.GM.
strawberry.plants.have.been.performed.in.Spain,.Great.Britain,.and.Italy.(Table.5.2)..
In.Great.Britain,.transgenic.plants.with.improved.resistance.to.insects.were.planted.
whereas.the.GM.plants.planted.in.Spain.were.evaluated.on.fruit.development,.fruit.
quality,. pollen. low,. and. out-crossing.. Unfortunately,. information. on. the. results.
of. these. studies. is. scarce.. More. information. is. available. for. the. Italian. ield. trial..
This.ield.trial.was.performed.at.the.Experimental.Farm.of.the.Marche.Polytechnic.
University. in. Agugliano.. Transgenic. plants. of. Fragaria vesca . cv.. 'Alpina. W..
Original'.and. Fragaria .×. ananassa .breeding.selection.AN93.231.53.expressing.the.
chimeric. DefH9-iaaM .gene.construct.and.nontransgenic.control.plants.of.each.were.
planted. in. the. ield. and. evaluated. for. fruit. traits. 34 . The. results. obtained. on. straw-
berry.were.nearly.identical.to.that.of. DefH9iaaM .transgenic.raspberries..Transgenic.
plants.showed.a.signiicant.increase.in.fruit.number,.fruit.size,.and.yield..They.had.
more.lowers.per.inlorescence,.an.increased.number.of.inlorescences.per.plant,.and.
parthenocarpic.fruits.on.emasculated.lowers. 39 .However,.GM.strawberries.are.still.
quite.a.long.way.from.commercial.use.in.Europe.
FOCUS OF RESEARCH ON GM FRUIT CROPS IN EUROPE
I mprovement of a GronomIcally I mportant t raItS
In.recent.times,.the.European.focus.of.research.on.GM.plants.has.switched.from.
the.development.of.eficient.regeneration.and.transformation.protocols,.including.
the.selection.of.suitable.marker.genes.to.the.improvement.of.selected.agronomi-
cally. important. traits.. Whereas.earlier. studies. were. mostly. aimed. at. the. method.
of.gene.transfer.itself,.newer.studies.are.focused.on.the.development.of.products.
with. improved. traits. for. introduction. into. the. market.. For. apple. and. pear,. traits.
like.resistance.to.insects,.bacterial.(ire.blight.caused.by. Erwinia amylovora .is.the.
main. disease. in.Europe). and. fungal. diseases.(scab.and. mildew),.stress. tolerance.
(cold,.heat),.precocity,.color.and.health.properties,.and.reduced.allergenic.potential.
are.of.particular.importance..For. Prunus .species.the.improvement.of.resistance.to.
the. PPV ,.the.most.dangerous.pathogen.in.Europe,.is.the.primary.goal..The.studies.
on.small.fruits.like.strawberry.are.mainly.aimed.at.the.improvement.of.resistance.
to.insects,.viruses,.and.fungal.diseases.(e.g.,. Verticillium dahliae ,. Botrytis cinerea ,.
and. Colletotrichum acutatum ).. Other. traits. such. as. salt. or. freezing. tolerance,.
reduced.softening,.sugar.content,.fruit.color,.lavor,.ripening,.and.yield.are.also.of.
importance.
u Se of e arly f lowerInG Gm p lantS to a ccelerate b reedInG c ycleS
Recently,. a. study. was. published. by. a. German. group. which. describes. the. use. of.
transgenic. apple. plants. with. a. reduced. juvenile. phase. for. applied. breeding.. The.
transgenic.plants.were.used.to.accelerate.the.breeding.process.because.fruit.tree.
breeding. is. time. consuming,. requires. substantial. space,. and. is. therefore. very.