In order to obtain transgenic maize plants tolerant to salt stress, maize inbred Zheng 58 was transformed with BADH gene using pollen-mediated method. The results of Km-resistant screening, PCR detection and Southern blot analysis proved that BADH gene was introduced into maize plants and integrated into the maize genome. Effects of various concentrations of NaCl solution on the growth of T2 transgenic and non-transgenic maize plants were investigated.The results indicated that transgenic maize seedlings had an improved resistance to salt stress, and their growth performance was superior to that of non-transgenic maize seedlings. On the basis of the growth status of non-transgenic plants, 250 mmol L–1 of NaCl solution was used to screen transgenic plants. An analysis on morphological and physiological indexes under the stress of 250 mmol L–1 NaCl showed that compared with non-transgenic plants, the seedling height of transgenic plants was increased by 10.94%–25.70%, fresh weight was increased by 8.62%–18.20%, dry weight was increased by 9.00%–18.18%, relative conductivity was decreased by 37.21%–58.14%, chlorophyll content was increased by 15.89%–90.65%, superoxide dismutase (SOD) activity was increased by 64.92%–148.29%, and MDA content was decreased by 26.97%–48.05%. In conclusion, introducing betaine aldehyde dehydrogenase (BADH) gene enhances salt tolerance in maize plants. This is the first report on introducing BADH gene into the elite maize inbred Zheng 58. This study suggests that pollen-mediated transformation approach is an economical, effective and practical plant trans-formation method without genotype dependence.
MaizeBADH geneGenetic transformationSalt toleranceMorphological indexPhysiology index