Pre-breeding for stress related traits in sugar beet

Water-nutritional stress frequently occurs in many sugarbeet growing areas. Knowledge of root morpho-physiological traits involved in the adaptation to above stress is needed to improve sugar yield. Thirty sugarbeet breeding lines varying in sugar yield were evaluated for differences in root elongation rate and nutrient (sulfate) uptake rate in response to its deprivation. Seedlings were grown hydroponically in a 16-h light, 8-h dark period (photon flux density of 300 μmol m-2 s-1) for 15 days in a complete nutrient solution. In order to obtain sulfate deprived seedlings, sulfate was replaced by chloride at the sixth day. Wide genetic variability was observed among the genotypes examined for the above traits. Significant relationships among the “root elongation rate”, “sulfate uptake” traits and sugar yield were observed. Use of this knowledge might be useful for comparative morpho-physiological and molecular studies aimed to assist sugarbeet breeding through marker assisted selection.