Crop Biotech Update

Shoot Tip Transformation Technology for Maize

December 5, 2012

A research team from Tianjin University, China established an effective and simple technology of maize genetic transformation. Using shoot meristems of two different maize inbred lines maternal tian tawu and 7922, phytoene synthase (psy) gene was transferred into maize by Agrobacterium-mediated transformation. Factors influencing transformation efficiency were optimized in this research.

The results indicated that the optimal transformation condition includes an infection time with vacuum at 20 min and co-cultivation time of 3 days. The transgenic plants were obtained after selection with 200mg/L phosphinothricin (PPT) whereafter, 16 lines were confirmed positive by PCR amplification. RT-PCR and HPLC analysis showed that psy gene had been integrated into the maize genome and transcribed normally. The total carotenoid content in transgenic maize increased 25% compared to the wild type. This method eliminates the tedious process of tissue culture and proves to be a simple, strong operability transformation method. Phytoene synthase is a rate-limiting enzyme in the pathway of carotenoid biosynthesis. This research could be the basis for elevating the nutritive value by encouraging the composition of corresponding carotenoid.

See the paper published by China Biotechnology at For more information visit