Salt tolerant sugarbeet progeny from tissue cultures challenged with multiple salts

Lines of sugarbeet (Beta vulgaris L.) tolerant of multiple salts was accomplished by an in vitro multiple salt challenge. Petioles were placed on RV medium amended with 5 different salts along with Murashige and Skoog base salts for one month. Surviving shoots were cultured on RV medium to obtain petioles for subsequent challenges. During the first, second and third challenges, organogenically regenerated shoots developed from 5%, 46%, and 80% of the petioles, respectively. After the third multiple salt challenge, tolerant shoots were rooted and transplanted in soil. Salt was added to this soil at 1.0% by weight and plants were observed for 2 months. The ten most salt tolerant plants were vernalized to obtain seed. The R1 seed and controls were planted in soil containing 0%, 0.61% or 0.77% multiple salts per dry soil weight. Emergence of R1 seedlings was significantly greater than the controls under salt stress. Multiple salt tolerant R1 plants were maintained in salt amended soil to the 8-10 leaf stage and appeared as healthy and vigorous as the control growing in salt free soil.