Written By: Michelle Klug
Photos provided by: Dr. Wagner Vendrame
Finding alternative, renewable sources of energy is essential to meet our nation’s future energy challenges. One alternative that holds promise is to tap into agriculture to grow some of our future fuel needs.
Jatropha is a plant whose seeds produce oil so pure, you can practically pour it right into the tractor which plowed the land it grew from. The Jatropha plant is a candidate for future biofuel production – a hardy small, drought-resistant tree that produces seeds containing oil suitable for premium biofuel production.
IFAS Researcher Wagner Vendrame, located at the Tropical Research and Education Center in Homestead, investigates this plant and creates cultivars and growing practices for future sustainable fuel production.
Jatropha as an Ideal Plant for Biofuel Production
"There is tremendous interest in Jatropha as a biofuel crop because of the final product – the oil that comes from the seeds," Vendrame said. "It has excellent qualities to be used as a biofuel – specifically to be used as biodiesel and as jet fuel."
The small trees produce green fruit, about the size of a ping pong ball. The fruit usually holds three seeds, which are removed and crushed by a press to extract the oil.
The raw oil itself has noteworthy qualities. "You could take the crude oil and put it in any diesel engine and it will work really well – it’s amazing."
However, before the oil reaches engines, it undergoes transesterification, a process which cleans the oil and removes the Glycerin, which would cause buildup in engines. It is an inexpensive and efficient process that can operate in a small room.
"Once the Glycerin is removed from the oil, you have pure biodiesel," Vendrame said. The oil produced from this process goes beyond the specifications that exist in the biodiesel industry and is considered premium fuel. The Glycerin byproduct can be sold to pharmaceutical or cosmetic companies.
The oil can be used by diesel engines and is also ideal to be mixed with jet fuel due to its stability at low temperatures.
Using Plant Genetics to Create an Optimal Cultivar
Although Jatropha oil holds ideal qualities for biofuel production, it is still a wild plant. Cultivars have not been developed for commercial farming. Breeding and genetic improvement still need to be done before farmers can grow this crop commercially.
Vendrame said genetics play a major role in developing a model cultivar.
"For breeding and genetic improvement of any crop, you need to tap in to the natural genetic variability that occurs in the plant."
Vendrame and his team are working with 17 different varieties from 12 different countries. After growing the different varieties of Jatropha, the team assesses over 50 characteristics such as fruit production, flowering and seed weight, in order to select genotypes of Jatropha that are best for breeding and creating new cultivars.
In order to go further and to learn about which genes control particular processes, the researchers performed genetic sequencing and got a partial sequence of the Jatropha genome - a process that allowed them to identify over 100,000 genes.
"We can better tailor genetic improvement by targeting specific genes," Vendrame said.
The researchers identified genes that express cold tolerance and also genes that relate to oil production. By manipulating those genes, the researchers are trying to create future cultivars that resist low temperatures and produce more oil.
Biotechnology is used to multiply the plants which exhibit desirable characteristics. In vitro clonal propagation of plant tissue culture is used to create clones of the Jatropha for distribution to growers.
Jatropha Space Shuttle Expeditions
Sparked by previous experiments that have proven plant cells grow and function differently in microgravity, Vendrame and his team partnered with NASA to send Jatropha into orbit in 2010. A preliminary experiment in 2007 demonstrated that the plant cells have a much different growth pattern in space. They grow much faster and at a much higher volume.
Subsequent space shuttle experiments have examined differential gene expression.
"In microgravity, there will be some genes of Jatropha that become activated and might assist in improving the plant genetically," Vendrame said.
Researchers hope the space shuttle experiments will accelerate the breeding program and the genetic improvement of Jatropha, and help create a commercial cultivar with desirable characteristics such as cold tolerance and high oil content.
"If we can tap into a more renewable and environmentally friendly source of fuel, we can help set the stage to meet our country’s future energy needs," Vendrame said.