Plasmid pCBl, which contains a bar gene under the control of CaMV 35S promoter, had been successfully transformed into immature embryos of japonica rice (about 12 days after flower) using biolistic method. The bar gene was isolated from Streptomyces hygroscopicus. It encodes for phosphinothricin acetyltransferase (PAT) that confers resistance to phosphinothricin (PPT), the active ingredient of the broad - spectrum herbicide Basta. After bombardment, the Basta resistant calli were induced from bombarded immature embryos and several Basta resistant transgenic rice plants were then regenerated. Basta resistance test showed that all transgenic plants were highly resistant to Basta compared with the un-transformed control plants. The integration of bar gene in the genome of the transgenic rice plants was confirmed by PCR and Southern analysis. The primers used in PCR were primer 1:5' - GCCATCATTGCGATAAAG-GA-3'and primer 2:5'GTAACATAGATG-ACACCGCG - 3'. RNA dot blot analysis demonstrated the mRNA expression of the bar gene at the tanscriptional level in transgenic plants. Among 321 T_1 progenies, 274 plants showed high resistance to Basta, other 47 plants were sensitive. According to the Southern analysis of 8 randomly selected plants from those 274 Basta resistant plants, bar gene was stably inherited to the T_1 progenies.
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