Acetosyringone, pH and temperature effects on transient genetic transformation of immature embryos of Brazilian wheat genotypes by Agrobacterium tumefaciens

作者：Manfroi Ernandes; Yamazaki Lau Elene^*; Grando Magali F; Roesler Eduardo A

来源：Genetics and Molecular Biology, 2015, 38(4): 470-476.

DOI：10.1590/S1415-475738420150026

• co-cultivation conditions
• protocol establishment
• GUS
• T-DNA delivery

Low transformation efficiency is one of the main limiting factors in the establishment of genetic transformation of wheat via Agrobacterium tumefaciens. To determine more favorable conditions for T-DNA delivery and explant regeneration after infection, this study investigated combinations of acetosyringone concentration and pH variation in the inoculation and co-cultivation media and co-culture temperatures using immature embryos from two Brazilian genotypes (BR 18 Terena and PF 020037). Based on transient expression of uidA, the most favorable conditions for T-DNA delivery were culture media with pH 5.0 and 5.4 combined with co-culture temperatures of 22 degrees C and 25 degrees C, and a 400 mu M acetosyringone supplement. These conditions resulted in blue foci in 81% of the embryos. Media with more acidic pH also presented reduced A. tumefaciens overgrowth during co-culture, and improved regeneration frequency of the inoculated explants. BR 18 Terena was more susceptible to infection by A. tumefaciens than PF 020037. We found that it is possible to improve T-DNA delivery and explant regeneration by adjusting factors involved in the early stages of A. tumefaciens infection. This can contribute to establishing a stable transformation procedure in the future.

• 出版日期2015