One of the biggest stumbling blocks for the uptake of biofuels is the ‘food versus fuel’ debate, which argues that productive crop land should not be used to grow fuel crops.
Now researchers in the American Midwest have suggested that large-seeded vegetable crops, such as pumpkins, could be used in double-cropping systems producing both food and fuel crops.
Marty Williams, a University of Illinois crop scientist and ecologist with the USDA-Agricultural Research Service, explains, “Some vegetables have relatively short growing seasons, too. Rather than the standard fallow period for certain vegetables, what about integrating a bioenergy crop as a part of a double-cropping system?”
Williams chose pumpkin due to its popularity in the state of Illinois “We took a fairly simplistic look at comparing this bioenergy/vegetable double-cropping system with traditional vegetable production using processing pumpkin,” he explained. “Illinois leads the nation in pumpkin production, providing some 90 percent of the processing pumpkin in the United States.”
Interestingly, the researchers saw pumpkin yields in the double-cropping system were comparable to conventional pumpkin production. However, the biomass feedstock also yielded an average of 4.4 tons per acre of dry biomass prior to pumpkin planting. “We saw a theoretical yield of 349 gallons of ethanol per acre, and a higher farm gate value than typical pumpkin production,” Williams said.
“Perhaps some of our vegetable-cropping systems could contribute to bioenergy production, while still producing veggies. Also, there may be certain vegetable crops that are better suited to double-cropping. Given the potential competition between food and fuel production globally, systems making contributions towards both goals appear worth further consideration,” he added.