Optimization of the Genetic Transformation System of Lettuce

Lettuce (Lactuca sativa L.) is an annual vegetable crop of the family Asteraceae. It is the most consumed leaf vegetable in the world and is highly valued for its edible and medicinal value. Using transgenic technology, introducing functional genes into plants can shorten the breeding time and improve the quality of lettuce. However, in the genetic transformation of lettuce, the application of transgenic technology is limited by the low conversion rate. In this experiment, using ‘S39’ cotyledons as the test material, to establish a stable genetic transformation system. The results showed that when the leaf regeneration medium was 0.01 mg/L 6-BA and 0.4 mg/L NAA, the highest regeneration rate reached 97.9%, which was the best leaf regeneration hormone concentration. When the infection fluid was used in the OD600 value of 0.2, the infected leaves were in good condition and controllable Agrobacterium was the most suitable infection fluid concentration. When the infection time was 15 min, the infection effect was the best, the leaves grew well, and the resistant plants could grow. The screening in a medium containing 30 mg/L of Kana concentration and 250 mg/L of Cef was the suitable medium formulation. NAA 0.1 mg /L and 6-BA 0.2 mg /L were selected as the optimal concentrations in the rooting medium.