New Rice Breed Could Cut Methane Emissions by 70%

By Jill Dando News

Rice farming is a major contributor to global methane emissions, accounting for around 12% of the total.

As the world’s population grows and temperatures rise, these emissions are expected to increase.

But now, scientists have developed a new type of rice that could significantly reduce these emissions.

In a study published in Molecular Plant, researchers from the Swedish University of Agricultural Sciences revealed that they’ve bred a variety of rice that releases up to 70% less methane than regular rice.

Rice plants release methane through microbes in the soil that break down substances secreted by the roots. These substances, called root exudates, are part of a natural process that helps plants absorb nutrients.

For years, scientists knew that these exudates were linked to methane emissions, but it wasn’t clear which specific compounds were the cause.

The breakthrough came when the researchers studied two types of rice: one genetically modified (GMO) variety with low methane emissions and another traditional, non-GMO rice. They found that the GMO variety produced less of a compound called fumarate, which appeared to encourage methane-producing microbes in the soil.

By adding fumarate to the soil, methane emissions increased.

In contrast, using a chemical called oxantel to block the breakdown of fumarate led to a reduction in emissions.

But that wasn’t the end of the story.

The team also noticed that the GMO rice released more ethanol, another compound which seemed to reduce methane emissions. This discovery led them to wonder if traditional breeding could be used to create a new rice variety that both reduced methane emissions and maintained high yields.

The scientists crossbred a high-yield rice with a variety that naturally produced low methane. This new variety, which they’ve named LFHE (low fumarate, high ethanol), was tested in fields across China.

The results were promising: the LFHE rice emitted 70% less methane while still producing high yields of nearly 9 tonnes per hectare—well above the global average of 4.7 tonnes.

Encouraged by these results, the team is now working to register LFHE rice with the Chinese government. They hope this will allow farmers to grow the new, eco-friendly rice.

Researchers are also looking into whether the chemicals ethanol and oxantel could be used on a larger scale to reduce emissions without affecting crop yields.

However, as lead researcher Anna Schnürer points out, getting this new rice to market will require the support of governments and incentives for farmers to adopt the low-methane variety.

"It’s one thing to breed eco-friendly rice, but we also need to make sure it’s available to farmers," she said.

If successful, this new rice could play a key role in reducing methane emissions from one of the world’s most important food crops.

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