Jatropha curcas is the most publicized perennial oilseed species, but others such as Pongamia pinnata or Aleurites moluccana may eventually have uses in the advanced biofuel sector.
Jatropha curcas
- Toxins in seeds presently restrict human and livestock consumption.
- More than 300,000 hectares under commercial cultivation as of late 2010 across Asia, Africa, and Central and South America.
- Small tree (5-8m) native to Central America produces fruits within 1.5 years – trees can survive more than 50 years, although commercial production is expected to be viable through the first 30 years.
- Survives with as little as 600mm of rainfall annually, but is not commercially viable with less than 900mm annual rainfall.
- Seeds with oil content up to 40 percent by weight, with a yield range of 500 to 1,000 gallons per hectare possible in appropriate conditions; substantial residual biomass is also generated that can be used in industrial applications and/or as internal offsets to fertilizer expenditures.
- Higher yields can be achieved with improvements in plant science, agronomy, and mechanization of production systems.
- Used medicinally in many locations for centuries.
- Interest grew in 1980s-90s when the trees were used in conservation plantings to combat desertification.
- Despite many commercial failures related to planting heterogeneous, wild Jatropha varieties without sufficient agronomic knowledge, the Jatropha industry is poised for growth. Recent investments in Jatropha by firms such as PetroChina, IndianOil, Valero, Koch Industries, Tata Chemicals and Toyota Tsusho validate the maturation and promise of the emerging Jatropha industry.
Pongamia pinnata (or P. glabra)
- Mild toxins in seeds limit their consumption by humans and livestock.
- Multiple international R&D programs studying its use for biofuel developments in Asia and Australia.
- Large tree (up to 25m) native to southern Asia.
- Leguminous (nitrogen-fixing) species that can effectively combat desertification.
- Produces fruit by year 5, reaching maturity after 10 years – trees are expected to remain commercially viable for more than 50 years; long time to maturity presents barriers to investment in commercial applications of Pongamia.
- Seeds with oil contents up to 45 percent by weight, with potential yield ranges predicted to be 300 to 600 gallons per hectare at maturity in marginal soils.
- Higher yields in the long-term are potentially realizable with dedicated and extensive R&D programs addressing breeding and selection of superior materials, crop agronomics, and other management strategies such as establishment and harvest methods.
- Survives with as little as 450mm of rainfall annually and is expected to produce high yields in areas receiving approximately 650mm of annual rainfall.
- Tolerates low to moderate levels of soil salinity.
- Used medicinally in southern Asia for centuries to treat a variety of digestive ailments.
Other Species of Interest
- Aleurites moluccana – Kukui, or candlenut, tree
- Azadirachta indica – Neem tree
- Madhuca indica – Mahua tree
- Calophyllum inophyllum – Kamani, or punnaga, tree
- Croton megalocarpus – Croton tree
- Moringa oleifera – Ben-oil, or drumstick, tree (an edible species with many uses)