Sugarcane (NCo310) Transient Transformation Using uidA Reporter Gene

Background: Sugarcane is a monocotyledonous crop that is cultivated in the tropical and subtropical regions of the world. One of the most important criteria, influencing the efficiency of the sugarcane transformation is known to be related to physical and biological factors during the transformation procedure. Objectives: The objective of this research was to study the response of callus induction and embryogenic callus production and to identify the major parameters controlling DNA delivery by particle bombardment into sugarcane (Saccharum officinarum L.) cv. NCo310. Materials and Methods: For callus induction and embryogenic callus production, leaf base segments were subjected to in vitro culture medium supplemented with two plant growth regulators (2,4-D and Dicamba). Results showed that 1 mg.L -1 2,4-D was significantly influential in callus induction and embryogenic callus production. Considering both physical and biological factors, the efficiency of DNA (uidA gene) delivery was assessed by scoring transient GUS (gene (β-glucuronidase) ) expression in bombarded tissues. Results: The highest transient GUS expression was obtained when callus was bombarded with the construct harboring rice Act1 promoter, and having 9 cm target distance, 25 inHg vacuum pressure, 1 µm gold particles, 12.5 µg DNA per bombardment and one day pre-culture prior to the bombardment. Conclusions: A bombardment procedure suitable for elite sugarcane varieties was developed, which allowed high-efficiency DNA delivery combined with reduced damage to target tissues.