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Powdery mildew is a deadly fungus that can damage large stocks of wheat all over the world.

Now researchers in China have, for the first time, found a way to make wheat resistant to this lethal pathogen by 'deleting' specific genes within the plant.

The research team were able to 'snip' genes responsible for weakening wheat's defence against the fungus.

Researchers in China have, for the first time, found a way to make wheat resistant to powdery mildew by 'deleting' specific genes within the plant

The work, carried out by researchers at the Chinese Academy of Sciences in Beijing, could someday eliminate the need to use chemical compounds to control disease in crops.

It also means that scientist can change wheat's genetic make-up without inserting foreign genes – which has been one of the main criticisms of genetically modified food.

David Talbot at the MIT Technology Review explains that the gene-deletion trick is particularly tough to do in wheat because the plant has a hexaploid genome.

Powdery mildew (pictured) is a deadly fungus that can damage large stocks of wheat all over the world. The research team were able to 'snip' genes that responsible for weakening wheat's defence against the fungus

That means it has three similar copies of most of its genes and multiple genes must be disabled for the wheat to become resistant.

Using tools such as 'Crispr', the researchers were able to do that without changing anything else or adding genes from other organisms.

Crispr – pronounced 'crisper'- targets the genome's source material and permanently turns off genes at the DNA level.

The DNA cut – known as a double strand break – closely mimics the kinds of mutations that occur naturally, for instance after chronic sun exposure.

But unlike UV rays that can result in genetic alterations, the Crispr system causes a mutation at a precise location in the genome.

When cellular machinery repairs the DNA break, it removes a small snip of DNA. In this way, researchers can precisely turn off specific genes in the genome

"We now caught all three copies, and only by knocking out all three copies can we get this [mildew]-resistant phenotype," Caixia Gao, who headed the study told MIT Technology Review.

Professor Gao has now filed a global patent on the technology, however no field trials have yet been planned.

The breakthrough follows earlier news this week that researchers at the University of California Davis have managed to map the genetic sequence of wheat for the first time.

The experiment could help farmer already benefiting from the genetic modification of wheat produce better strains.

It may also help accelerate research such as Professor Gao's, and have an impact on others like it.

Crispr technology precisely changes target parts of genetic code. Unlike other gene-silencing tools, the Crispr system targets the genome's source material and permanently turns off genes at the DNA level