Identification Of Salt-tolerance Of Transgenic Potato With BADH Gene

Salinity is one of the most important abiotic stresses that affect the normal growth and development of plants. Improvement of crops and breeding of new varieties to increase their drought and salinity tolerance is the most economic and effective ways for using arid and salty soils. With the rapid development of modern molecular biology, the great progress has been achieved in improving crop drought and salinity tolerance by genetic engineering. One of the fundamental physiological mechanisms of high plant to cope with environmental stresses is osmotic adjustment, and glycine betaine is regarded as one of the most promising osmolytes.Potato is sensitive to salinity and unable to synthesize glycine betaine. Introduction of genes related to glycine betaine synthesis and establishing a glycine betaine biosynthetic pathway in glycine betaine-deficient potato through genetic engineering, which could be enhanced salinity tolerance of potato. Zhang Ning (2004)isolated BADH gene which is the key enzyme for glycine betaine synthesis from spinach (Spinacia oleracea L.),and introduced them into potato cultivar firstly. Then transgenic potato plants were obtained . The main purpose of the studies is the identification of salt-tolerance in the potted plant of seven transgenic potato plant lines S1,S2,S3,S4,S5,S6,S7 of the second asexual multiplication generation with BADH gene and the recipient parent potato Gannongshu 2(S0) under the concentration 0%, 0.3 % and 0.6% NaCl stresses. The major results are as follows:1. The detection by PCR showed that the BADH gene had higher genetic stability in the transgenic plants.2. The detection of BADH enzyme activity demonstrated that expression of the BADH gene was detected in seven transgenic plant lines and induced by NaCl stress in the plant lines S5,S6 and S7,while it was not detectable in the untransgenic plants.3. The plant lines S1,S2,S4 ,S6 and S7 transformed with BADH gene had relatively higher salt tolerance under the concentration 0.3% NaCl stress. The plant lines S4 and S7 had relatively higher salt tolerance under the concentration 0.6% NaCl stress. Thus the plant lines S4 and S7 had higher salt tolerance.