EXPRESSION OF BETAINE ALDEHYDE DEHYDROGENASE GENE AND SALINITY TOLERANCE IN RICE TRANSGENIC PLANTS

Betaine as one of osmolytes plays an important rule in osmoregulation of most high plant. Betaine aldehyde dehydrogenase (RADH) is the secon d enzyme involved in betaine biosynthesis, The BADH gene from a haloph ite, Atriplex hortensis was transformed into rice cultivars by bombarm ent method. Totally 192 transgenic rice plants were obtained and most of them had higher salt tolerance than controls. Among transgenic plan ts transplanted in thr saline pool containing 0.5% NaCl in a greenhous e, 22 survived, 13 of which set seeds, and the frequency of seed setti ng was very low, only 10%. But the controls could not grow under the s ame condition. The results of BADH activity assay and Northern blot sh owed that the BADH gene was integrated into chromosomes of transgenic plants and expressed.