الفهرس 
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Abstract
*Lupinus termis (lupine) seedlings of 20-day old were exposed to UVC for various time intervals (20, 40, 60, 80 and 100 min) and various concentrations of the aqueous leaf extract (20, 40, 60, 80 and 100 µg ml-1) were prepared from lupine leaves of irradiated and non-irradiated seedlings (control). *The total phenol content in lupine leaves from non-irradiated seedlings (Control) was 51.6 mg g-1 DW and increased gradually with the time of exposure to UVC and reached 65.3 mg g-1 DW after 100 min. *Portulaca oleracea plants were grown after treatment with the above concentrations (20, 40, 60, 80 and 100 µg ml-1) and then various analyses were carried out for determination of the various investigated parameters. *The total flavonoids in lupine leaves increased continuously by UVC treatment and the increase was time-dependent. The control value was 22.4 mg g-1 DW, which increased and reached 45.0 mg g-1 DW after 100 min exposure to UVC. *Germination percentage of P. oleracea decreased continuously with increasing the concentration of irradiated and non-irradiated lupine leaf extracts. *The activities of chalcone synthase (CHS) and phenylalanine ammonia lyase (PAL) in Portulaca leaves were enhanced after treatment with irradiated and non- irradiated lupine leaf extracts. However, the irradiated lupine leaf extract was more effective than the non-radiated one. *The total flavonoids in Portulaca leaves increased in concentration-dependent manner after treatment with lupine leaf extracts. It was observed that lupine leaf extracts enhanced the total flavonoids particularly the non-irradiated one throughout all the concentrations. *There was a remarkable increase in the activities of flavonoid-3-monooxygenase (F3M) and cinnamate-4-hydroxylase (C4H) in concentration-dependent manner after treatment with irradiated or non-irradiated lupine leaf extract. It was shown that irradiated lupine extract exhibited higher activity of F3M than non-irradiated one at the various tested concentrations. *Vitamin E and reduced glutathione (GSH) as non-enzymatic antioxidants increased continuously in P. oleracea leaves after treatment with lupine leaf extract whether irradiated or non-irradiated in concentration-dependent manner. *There was remarkable continuous increase in oxidized glutathione (GSSG) content in P. oleracea leaves after treatment with non-irradiate and irradiated lupine leaf extracts. It was remarkable than the GSSG content in the leaves increased with higher rate after treatment with irradiated lupine leaf extract compared with non-irradiated leaf extract. *The ascorbate content in P. oleracea leaves was enhanced in concentration-dependent manner after treatment with non-irradiated and irradiated lupine leaf extracts. It should be stressed that irradiated leaf extract of lupine induced ascorbate content with higher rate compared with the induction by non-irradiated extract. *The results showed that an increase in dehydro-ascorbate of P. oleracea leaves after treatment with non-irradiated or irradiated lupine leaf extracts. The irradiated lupine leaf extract exhibited a remarkable higher increase depending on the concentration compared to the non-irradiated lupine leaf extract. It was observed that after treatment with 100 mg ml-1 the content of dehydro-ascorbate declined after both treatments. *Continuous increase in H2O2 and malondialdehyde (MDA) in P. oleracea leaves after treatment with irradiated and non-irradiated lupine leaf extracts. *The activity of NADH-oxidase in P. oleracea leaves after treatment with irradiated and non-irradiated lupine leaf extract. The enhancement was more remarkable with irradiated lupine leaf extract compared to the non-irradiated one. *The activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) in P. oleracea leaves increased gradually in a concentration-dependent manner after treatment with both extracts of lupine leaf. It was found that the induction of the three enzymes with irradiated lupine leaf extract was higher compared with non-irradiated extract. *DPPH (2,2-diphenyl-1-picrylhydrazyl) (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) scavenging activities of P. oleracea leaves treated with irradiated lupine leaf extract was higher than those of non-irradiated one. Also, it was observed that ascorbate which is used as standard scavenger exhibited higher scavenging activity compared to the irradiated and non-irradiated lupine leaf extracts. *Treatment of P. oleracea with irradiated lupine leaf extract decreased the total soluble carbohydrate content in their leaves, and this content was lower than that measured after treatment with non-irradiated lupine leaf extracts. *Under allelopathic effect of lupine leaf extract, whether irradiated or non-irradiated, on P. oleracea the activities of Ribulose 1,5-bisphosphate carboxylase/ oxygenase (Rubisco) and glyceraldehyde-3-phosphate dehydrogenase (G-3-P DH) in Portulaca leaves declined in concentration-dependent manner. This decline in the activities of the two enzymes of Calvin cycle explains the reason behind reduction of total soluble carbohydrate. The total soluble protein content in P. oleracea leaves was reduced after treatment with irradiated and non-irradiated lupine leaf extract. The reduction in both treatments was dependent on the concentration.Under treatment of P. oleracea with lupine leaf extracts continuous reduction in the activities of nitrate reductase and nitrite reductase in Portulaca oleracea leaves which explains the reduction in total soluble nitrogen.