الفهرس 
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Abstract
This investigation includes the results of a large scale experiment carried out; in response to treatment with various abiotic stressful factors (salinity and cadmium) either alone or in combination with protective compounds. The main points that can be extracted from the experimental results are given in the following: Treatment of broad bean plants with 300 mM NaCl and /or 1 mM Cd, induced, in general, significant decreases in all the determined growth parameters and pigment fractions and increases in poline content, H2O2 content, lipid peroxidation and electrolyte leakage, as compared with the control values. Moreover, the content of antioxidant compounds were increased in broad beans treated with NaCl and/or Cd except anthocyanin and ascorbic acid contents on the 10th day were reduced, as compared with the control values. Except for CAT activity which was significantly decreased after 20 days, all the activities of CAT, APX, GR, SOD and PPO in broad bean plants, treated with NaCl and/or Cd showed significant increases above the control values. NaCl and/or Cd stress caused a decline in the DPPH-scavenging activity and an increase in total antioxidant activity, as compared with the control values. On the other hand, treatment with AsA induced a significant increase in growth parameters above the respective control values throughout the experimental period. In contrast, application of SA, in general, elicited a significant decline in the determined growth parameters. Exogenously application of adaptive compounds induced increases in all pigment fractions and decreases in proline content, H2O2 content, lipid peroxidation and electrolyte leakage throughout the experimental period. The sole treatment with AsA or SA caused, in general, decreases in anthocyanin, flavonoid and total phenolic contents and total antioxidant activity and increases in ascorbic acid and glutathione contents and DPPH-scavenging activity, as compared with the control values. The supplemental addition of these compounds to the stressed plants generally induced significant decreases in activities of the determined antioxidant enzymes, below those values maintained in the stressed plants, on the 10th day. However, the activities of CAT, APX and GR showed significant increases above the values of stressed samples on the 20th day after treatment. The combination of the mentioned adaptive compounds with NaCl and Cd caused increases in growth parameters and all pigment fractions and decrease in proline content, H2O2 content, lipid peroxidation and electrolyte leakage, in relation to those values in the NaCl- and Cd-stressed plants. Furthermore, the antioxidant compounds and antioxidant activity appeared to be increased except anthocyanin and glutathione contents after 20 days decreased. On the other hand, the supplemental addition of these compounds to the stressed plants generally induced significant decreases in activities of the determined antioxidant enzymes, below those values maintained in the stressed plants, on the 10th day. However, the activities of CAT, APX and GR showed significant increases above the values of stressed samples on the 20th day after treatment. As a final conclusion, we can state that the adaptive (protective) compounds (AsA and SA) appeared to variously nullify the deleterious effects of the stressful factors (NaCl and Cd). As being evident from sections I to VII, profound changes in growth, photosynthetic pigments, proline content, H2O2 content, lipid peroxidation and electrolyte leakage as well as antioxidant compounds and enzymes were observed in response to supplemental addition of the adaptive compounds to the stressed broad bean plants. As being apparent from the present detailed results, varied degrees of nullification of the deleterious effects were observed and the adaptive AsA compound appeared to be more effective.