Effect of Presoaking Sugar Beet (Beta vulgaris L.) Seeds with Gibberellic, Abscisic or Ascorbic Acids on Alleviation of Salinity Stress
Elsayed A. A. Abdelraouf
A study was conducted to investigate the effect of presoaking of sugar beet (Beta vulgaris L.) seeds (polygerm) with gibberellic acid, abscisic acid, or ascorbic acid on alleviation of salt stress at seedling stage. The salinity levels of irrigation solution were 0, 25, 50 and 100 mM NaCl and the presoaking treatments were water as a control, 10 µM GA3, 10 µM ABA, and 0.5 mM ASA for 12 hrs. Seeds were sown in plastic pot containing 0.8 Kg prewashed sand and irrigated three times weekly by 100 mL per pot of one-tenth modified Hoagland solution containing the salt level. After seven weeks from sowing, the whole plants were collected. The results indicated that increasing salt concentration decreased the fresh and dry weight of whole plant, shoot and root, and shoot height of all presoaking treatments. However, shoot/root ratio on fresh and dry weight basis and moisture content of whole plant, shoot and root, chlorophyll content index, and electrolyte leakage were increased with increasing salt concentration of all presoaking treatments. However, presoaking of sugar beet seeds (polygerm) with the GA3, ABA, or ASA showed no significant effect to alleviation salt stress on sugar beet seedlings. However, the interaction between salt levels and presoaking treatments was significant for whole plant and root fresh and dry weights, shoot/root ratio on fresh weight basis, whole plant and root moisture content and chlorophyll content index, while nonsignificant for shoot fresh and dry weights, shoot height, shoot/root ratio on dry weight basis, shoot moisture content and electrolyte leakage. Keywords: Salt stress, sugar beet, gibberellic acid, abscisic acid, ascorbic acid, presoaking.