Improving the acclimatization and establishment of Arundo donax L. plantlets, a promising energy crop, using a mycorrhiza-based biofertilizer

Arundo donax has become one of the most promising species for cellulose paste, biomass, and second-generation biofuel production. Because this species is not able to produce viable seeds, micropropagation is the best method for large scale production. Several studies have demonstrated that arbuscular mycorrhizal fungi (AMF) can improve the acclimatization of micropropagated plantlets, enhancing their growth and survivalin this study, we evaluated the effect of AMF during the acclimatization period of A. donax plantlets and its posterior establishment to the field. Plantlets were inoculated with mycorrhiza-based biofertilizer (AEGIS SYM (R)) that contained Rhizophagus intraradices and Funneliformis mosseae. The inoculum was applied at the time of transplantation of plantlets to 28-cm(3) cell trays filled with commercial nutrient-rich agricultural substrate. The results showed that during acclimatization, mycorrhized plantlets (AM) present higher number of leaves and height increments as compared to non-mycorrhized plantlets (control). Moreover, at the end of the hardening process, AM plantlets presented higher height, number of leaves, biomass, shoot:root ratio and chlorophyll a and b content than control plantlets. After open field establishment, AM plantlets presented greater size, number of stems and survival rate. These results demonstrate that inoculating micropropagated A. donax with AMF enhances its growth and development as well as produces better quality plantlets, which can be very useful for the large-scale production of this energetic crop. (C) 2014 Elsevier B.V. All rights reserved.