Potential and challenges in making physic nut ( Jatropha curcas L.) a viable biofuel crop: the Brazilian perspective.

Abstract

Abstract Fossil-derived fuels currently supply 86% of the world's energy, even though it represents a finite resource. With the aim of reducing the fossil fuels dependency, alternative sources of energy have been pursued in recent years. In view of the urgent need to develop new technologies that may enable environmentally friendly forms of energy to become widespread, biofuels in general and biodiesel in particular are receiving considerable attention throughout the world and especially in Brazil. Given the high quality of its oil, which meets the rapeseed quality standard and can be easily converted into biodiesel, and because of its wide adaptability, physic nut has been considered a potential crop to serve as feedstock for biodiesel production. Popular claims, e.g. enhanced drought tolerance, low nutrient requirements, pest and disease resistance, have also helped to increase the expectations of the crop, even though most of these claims are yet to be supported by scientific evidence. However, the fact is that besides its advantageous characteristics, physic nut cultivation is challenging as it is a quasi-undomesticated species. In that context, this review seeks to demonstrate the physic nut potential as a biofuel crop, highlighting, however, the challenges to its wide adoption as a fuel crop. Despite facing enormous challenges (as detailed below), our cautiously optimistic vision is that a substantial and focused research programme may make physic nut a viable feedstock for biodiesel production. We detail the Brazilian research initiative that is addressing many of these challenges.