الفهرس 
Introduction and Aims of the WorkOnly 14 pages are availabe for public view
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Abstract
The experiments of the present study were conducted in the Plant Tissue Culture and Biotechnology Labs, Maryuot Research station, Desert Research Center, Egypt and the Department of genetics, Faculty of Agriculture, Alexandria University, Alexandria, Egypt.
Seriphidium herba-album is very important medicinal plants that have been used in folk medicine for many years till now for the treatment of gastric disturbances and healing
external wounds, remission of diabetic symptoms, activating of the liver and healing rashes, joint pains, inflammations and rheumatoid arthritis, with no side-effects. S. herbaalbum belongs to Artemisia genus, family of Asteraceae which contains about 23000
species. Artemisia genus plant produces a various number of secondary metabolites that showed biological activity. Artemisinin is sesquiterpene lactones. This substance is known
for its medical efficacy, antioxidant, strong anti-inflammatory, antitumor activity, antimalarial, and for the fact Artemisinin could increase immunity.
The results:
1. Establishment of a regeneration system for (Seriphidium herba-album)
1.1. The highest percentage of Culture asepsis in the stem nodal section explants was (90%) with (73.33%) survival. This result was obtained when used 25% of sodium hypochlorite (Clorox) for 20 minutes then soaking in 0.1 % mercuric chloride (HgCl2) for five minutes
1.2. The highest callus induction percentage (97.44%) and callus fresh weight (7.89 gram) were obtained on MS medium supplemented with 1.5 mg/L 2, 4-D and 0.5 mg/L BAP after four weeks from callus culture 1.3. The highest percentage of somatic embryos formation (95.30%) and the average
number of somatic embryos per 1.0 g fresh weight of embryogenic callus (86.38) wre obtained on MS medium supplemented with 5.0 mg/L BAP and 0.5 mg/L NAA compared to the other treatments after eight weeks from callus calture 1.4. The best results of somatic embryo germination percentage (89.75%) and mean shoot length (3.98 cm) of the Seriphidium herba-album were obtained on MS medium supplemented with 3.0 mg/L GA3 and 1.0 mg/L kinetin compared to the other treatments after eight weeks from callus calture 1.5. The highest percentage of shoots that forming roots reached value of 100% and the
highest mean number of roots/shoot (25.0%) and the highest mean length of
roots/shoots (9.0 cm) were on MS medium free-hormone 1.6. The survival rate 100% after four weeks from the removal of transparent bags plantlets were maintained successfully. It decreased to 97% after 10 weeks of acclimatization 73
2. Enhancement of Artemisinin production from Seriphidium herbaalbum callus
Different concentrations from Jasmonic acid (JA), Salicylic acid (SA) and Sucrose (SU) were used to enhance the Artemisinin production in callus cultures. Moreover,
measure their effect on callus biomass (callus fresh weight and dry weight).
Salsylic acid at 10, 20, 30, 40 mg/L; Jasmonic acid at 2, 4, 6, 8 mg/L and sucrose at 40, 50, 60 and 70 mg/L were aseptically added to callus cultivation medium (MS containing 1.5 2, 4-D and 0.5 BAP) for enhancing Artemisinin production. The results
were taken after four weeks from callus culture and it appear that Salsylic acid was better than Jasmonic acid and sucrose for enhancing Artemisinin content 2.1. When used SA. Maximum Artemisinin concentration 36.75 mg /mL/100 mg DW with
biomass (callus fresh weight 2.84 g and 0.13 g dry weight) on 40 mg/L SA.
2.2. When used JA. Maximum Artemisinin concentration was 34.94 mg /mL/100 mg DW
with biomass (callus fresh weight 5.74 g and 0.32 g dry weight) on 4 mg/L JA
2.3. When used Sucrose. Maximum Artemisinin concentration was 22.55 mg /mL/100 mg DW with biomass (callus fresh weight 11.52 g and 0.58 g dry weight on 50 g/L
3. Quantitative RT-QPCR for three main genes in Artemisinin bathway
The best concentrations of each elecitor that gave the highest Artemisinin content were also used to measure their effect on gene expression level compared with non- treated callus (control) Sucrose 50 g/L and Salsylic acid 40 mg/L increased the gene expression of
The key Artemisinin biosynthesis genes ADS and CYP71AV1 to (2.77; 39.124 fold chang) and (1.95; 6.916 fold chang) in order.
Jasmonic acid (8mg/L) inceased only CYP71AV1 gene expression to (36.252 fold
change) but decreased ADS gene expression to (0.031fold chang), probably due to the negative
feedback and all treatment (sucrose 50 g/L, Salsylic acid 40 mg/L, Jasmonic acid 8 mg/L) decreased DBR2 gene expression to (0.003, 0.005, 0.0059 fold chang) in order. It appears that
the decline in DBR2 gene expression level caused the Artemisinin content to increase.