Petroleum dependency is a challenge that can potentially be partly offset by agricultural production of biofuels, while decreasing net, non-renewable carbon dioxide output. Plants have not been domesticated for modern biofuel production, and the quickest, most efficient, and often, the only way to convert plants to biofuel feedstocks is biotechnologically. In the last few years the potential of the drought resistant tropical tree Jatropha curcas L. (Euphorbiaceae) for the production of biofuels and industrial products has been assessed by several groups. Various novel methods for the cultivation and genetic improvement of J. curcas have been presented. A trans-esterification process of the seed oil for its use as a biofuel was evaluated on an industrial scale (1500 t/a). grains to produce bioethanol and biobutanol and oilseeds to produce biodiesel compete directly with needs for world food security. The heavy use of oilseed rape releases quantities of methyl bromide to the atmosphere, which can be prevented by gene suppression. Second generation bioethanolic/biobutanolic biofuels will come from cultivated lignocellulosic crops or straw wastes. These presently require heat and acid to remove lignin, which could be partially replaced by transgenically reducing or modifying lignin content and upregulating cellulose biosynthesis. Non-precipitable silicon emissions from burning could be reduced by transgenically modulating silicon content.  There seem to be no health or environmental impact study requirements when the undomesticated biofuel crops are grown, yet there are illogically stringent requirements should they transgenically be rendered less toxic and more efficient as biofuel crops.