Sorghum, a new weapon in the fight against global warming

Sorghum, a new ally against climate change

Sorghum provides significant biomass yields for fuel and energy generation, as well as the ability to fix huge amounts of carbon in the soil and improve soil fertility.

As the amount of carbon dioxide in the atmosphere rises, the globe must contend with another issue: soil carbon scarcity. Soil carbon refers to the quantity of solid carbon contained in soil globally, and it is essential for the growth of life and agriculture, particularly in its organic form.

So much so that one of the key criteria in defining what is known in soil science as soil health, or, in other words, the capacity of the soil to maintain the support functions of the ecosystems that develop in it, is the capacity of the soil to store organic carbon.

Now, a new study titled Bioenergy sorghum’s deep roots: A review has been published in the journal GCB Bioenergy. A key to long-term biomass production on yearly farmland appears to have gained a new friend in the fight against agricultural soil carbon loss and fertility degradation. We’re talking about sorghum with high energy content.

Crops that produce energy

According to research led by John Mullet, professor of agricultural biology in the Department of Biochemistry and Biophysics at Texas A&M University, energy sorghum hybrids are tremendously exceptional at capturing and sequestering significant amounts of atmospheric carbon dioxide in the soil, improving soil fertility, and generating potential caloric emissions.

Mullet, a genomics and genetics expert, has been working on bioenergy sorghum variants with William Rooney, a researcher in the field of international crop breeding at Texas A&M University’s Department of Soil and Crop Sciences, for more than 15 years. In reality, the two have collaborated to create the ultimate annual plant, uncovering a strain with high biomass yields for the production of fuel, energy, and other biological products in their most recent study.

That’s not all, though. Their hybrid sorghum also has good drought resistance, nitrogen use efficiency, and a deep root system that allows it to get water and nutrients that other annual crops can’t. “Perennial bioenergy crops are thought to be the most sustainable since they require less inputs and can sequester more biomass than annuals,” Rooney notes. “Those statements are correct,” the researcher says, “but annual crop varieties are also required in US agriculture.”

Sorghum is a good carbon sequestering crop.

During the crop’s 155-day growing season, one hectare planted with the researchers’ bioenergy sorghum hybrid gathered roughly 7.6 tons of biomass in the form of dry roots, which developed to a depth of nearly 2 meters, according to the study.

“These new measurements make it easy to estimate how much carbon dioxide from the atmosphere could be collected by the roots. The figures can also reveal how many carbon credits a planted field could potentially earn “Rooney tells the story. “To be honest, the numbers are extremely encouraging.”

The figures are also important for understanding the crop’s potential to improve soil fertility and water-holding capacity by replenishing soil organic carbon, especially since previous research has shown that soil organic carbon levels on annual cropland in the United States have declined by 50% over the last 100 years.

“Cropping techniques, microbial activity, and land use change could all be contributing to this decrease in soil carbon levels,” the researcher notes. “Because of these complicated processes, forecasting how long it would take to replace the lost carbon will require advanced modeling, but the restoration process will most certainly take decades.”

Soil regeneration for energy

In the United States, there are millions of acres of abandoned and marginal cropland where Mullet and Rooney’s biocrop can be tested. Mullet explains that “several of these fields are on the Gulf Coast of Mexico, which is an ideal site for bioenergy sorghum production because to ample rainfall, lengthy growing seasons, and limited competition with cereal crops.” In addition, thanks to the work of both researchers, the crop has improved in terms of productivity, resistance, and composition throughout time.

“The most essential thing we can do is to keep researching sorghum’s bioenergetic optimization, as well as to assist in the design and construction of biorefineries that will process the crop’s products in the most efficient way,” the researcher says.

“These products, whether biofuels or carbon fixed by the plants, could generate carbon credits, potentially benefiting producers and industry,” says the researcher. “However, despite the Gulf Coast’s excellent potential for biofuel production, there are still no bioenergy research centers and very few biorefineries in the region,” he adds.

“This isn’t simply a biofuels project; it’s also a carbon capture and sequestration initiative,” Mullet explains.


Article Author Gerluxe Image: Freepik