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HOME En - Fr - Es - De English Insect defeats Monsanto. GM crop designed to resist insects eaten by rootworm

Insect defeats Monsanto. GM crop designed to resist insects eaten by rootworm

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September 5, 2011 francese_18x12 spagnola_18x12 italiana_18x12

vermi_mangiano_foglieAfter the success weeds resistant to herbicides have had, now even an insect is defeating technology in agriculture. A new strain of corn rootworm has appeared in the United States – rootworm being one of the “evil beasts” for European and American farmers – able to thrive on GM corn plants in the laboratory created by Monsanto to be immune from attack of the corn rootworm.

At the moment the problem has been scientifically proven to exist only in four fields in Iowa (it is suspected to exist in some fields in Illinois, but nothing has yet been scientifically proven) and is limited just to corn varieties engineered to resist corn rootworm thanks to a toxin called Cry3Bb1.

This new strain of corn rootworm has existed since 2009; it has taken time to test in the laboratory that the insects transmit the resistance to the toxin to their descendants.

Monsanto says that these varieties of maize are still 99% effective against rootworm, but we should consider how much the resistant insects have reproduced and distributed in the meantime.

The corn in question was produced in the laboratory by inserting into its genome the genetic characteristic of Bacillus thuringiensis, or the ability to reproduce a lethal toxin (theoretically) for the rootworm larva that eat the corn roots. The adults eat the leaves, even those of corn, but do less damage.

The traditional remedy against infestation is crop rotation: the larvae that are born in the spring hatch in land not sown with maize and die of hunger – even if the United States have recently begun to extend their appetite to the soybean roots.

But, increasingly in the U.S., the incentives to produce corn for biofuel have led to a monoculture: for years and years the soil is now consecutively reseeded with corn.

Rootworm-resistant strains have been found in fields where GM corn has been growing continuously for at least three years. Decision: adapt or die. And the corn rootworm has adapted.


The Financial Times is losing the Monsanto maize resistant to pests

AFP Monsanto maize attacked by pesticide-resistant insects

The essay in the journal PLoS ONE of the resistance to the Bt corn rootworm (via Huffington Post)

Translated by Michele Valleri