Arundo donax as an energy crop: pros and cons of the utilization of this perennial plant.

Arundo donax (giant reed) is a rhizomatous grass widely found in temperate and subtropical regions. Because of its capacity to grow vigorously in marginal land, it is considered as a dangerous weed plant. However, humans contributed to the dispersion of this plant around the world because Arundo is used it for multiple purposes such as reeds in woodwind musical instruments, roof thatching and fishing rods. In recent years A. donax, due to its high biomass production has been also considered as a promising energy crop. Nevertheless, some important issues must be addressed. In fact, A. donax is a sterile plant and its propagation is based on vegetative propagation (fragmentation of rhizomes or canes) and in vitro culture, making establishing the crop on a large scale very expensive. Furthermore the geneticists cannot carry out conventional breeding programmes, so improvement will be based on ecotype selection, chemical and physical mutagenesis, and transgenesis techniques. Another aspect to consider for a massive utilization of A. donax as an energy crop consists in the scarcity of data on long-term field experiments, since the duration of the crop's life is 12-15 years. Hence, in this short review, we will bring together the principal pros and cons of this new putative energy crop.