Advances in genetic transformation of sugarcane using direct somatic embryogenesis

BUDEGUER F.; RACEDO J.,; ENRIQUE R.; SORIA FEMENÍAS M.J.; CUENYA, M. I.; WELIN B.; NOGUERA A. S.; CASTAGNARO, A. P.

Congreso; XXX International Society of Sugarcane Technologists Congress; 2019

Over the last decade, effort has been expended to develop an efficient transformation system for sugarcane, where most of the protocols employ bombardment of genes into embryogenic callus. However, the time required to regenerate transgenic plants from callus is typically 24-36 weeks. An alternative that offers several advantages, including faster regeneration time, fewer subcultures and lower probability of occurrence of somaclonal variation, is Direct Somatic Embryogenesis (DSE). The aim of this work was to improve the transformation efficiency of commercial EEAOC sugarcane varieties by DSE. Different types of particles and age of embryos during the bombardment process were evaluated by using the green fluorescent protein (gfp) marker. Explants of the TUC 95-10 genotype were bombarded with gold or tungsten particles, both coated with pFB1 plasmid, containing the gfp gene under control of CaMV 35S promoter. The highest number of GFP stable expression spots was observed with gold particles. Furthermore, no significant differences were observed in the GFP-spot number between the different explants ages tested (10 and 18 days). However, in order to decrease the global time of the process, the lowest explant age is recommended. Results suggest that the combined use of both gold particles and leaf roll discs of 10 days as explant will improve the efficiency of genetic transformation of local sugarcane varieties.