EFFECT OF SEED PRIMING WITH AQUEOUS EXTRACTS OF CARROT ROOTS, GARLIC CLOVES OR ASCORBIC ACID ON THE YIELD OF VICIA FABA GROWN UNDER DROUGHT STRESS

Two drought stress treatments were applied on Vicia faba (cv. Giza 716) seedlings (14-days-old). Watering was not done for 14 days (Dl) or 22 days (D2) and left to grow on clay-sandy soil (2:1 w/w) till yield stage. The impact of seed priming by presoaking in the extract of carrot root (Cr), garlic cloves (G), or ascorbic acid (AA) on the alleviation of the hurtful influence of drought stress was studied. Results showed that drought stress (Dl and D2) caused reduction in glucose, sucrose and starch contents of the increased seeds and in the yield also, while the total soluble protein content was increased. Seed priming with G, Cr or AA reduced the deleterious effects of drought on yield attributes and metabolites of Vicia faba, with some enhancements over their corresponding control values. SDS-PAGE of the yielded seeds showed that Dl and D2 led to the appearance of some newly synthesized protein bands and disappearance of others. Priming with G, Cr or AA resulted in the re-appearance of the disappearing bands and the synthesis of new ones. ISSR-analysis of the D2-stressedyielded seeds showed that priming with G or Cr extracts resulted in the formation of one and two unique bands, respectively. Priming with AA caused the disappearance of one unique band (466 bp) which was restored under priming with G, Cr or AA. Seven newly synthesized bands appeared on priming.