الفهرس 
Materials and mithodsOnly 14 pages are availabe for public view
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Abstract
V-SUMMARY
This investigation was carried out at the Tissue Culture Unit, Horticulture Department, Faculty of Agriculture, Benha University during the period 2008 to 2011. Growing and healthy parts of either lavender or thyme plants were taken and subjected to running water for 10 minutes then sterilized by using 10% Clorox (Commercial bleach) with two drops of Tween-20 for 10 minutes .Then, washed 3 times with sterilized distilled water for 5 minutes. Explants i.e. leaf discs, internode cuttings and root cuttings were prepared and cultured. Different medium types, anti-oxidant treatments, cold treatments, auxin types,2,4-D concentrations, cytokinin types, BAP concentrations in either lavender or thyme and combination between 2,4-D and BAP concentrations during Callus formation of lavender plants. The above experiments were done on both lavender or thyme plants. Although, these treatments were succeeded with lavender ,they failed with thyme plant as they gave low quantity of Callus and further experiments were done only on lavender plants. Meanwhile, additives treatments were studied during Callus induction. Also, different hormonal balance treatments were used during Plantlets regeneration. In-addition, Cytokinin types and BAP concentrations were studied in Proliferation. Meanwhile, auxin types & IBA concentrations were evaluated in Rooting On the other hand, oil percentage & composition were determined by using different additives i.e. Yeast extract, Glycine and Tryptophane and storing Callus for different periods.
The obtained results can be summarized as follows:
1.In vitro propagation:
1.1.Callus formation:
1. Modified Murashige and Skoog medium proved to be the best medium type used as it decreased Necrosis and maximized other Callus formation parameters i.e.Necrosis, Callus development, and Callus maturation.
2. Leaf discs were superior than other explant types as it reduced Necrosis while increased Callus formation, Callus development and Callus maturation.
3. Exposing the explant to cold treatment for 7 days (keeping in refrigerator at 4°C) encouraged the best Callus formation parameters (reducing Necrosis while improved Callus formation, Callus development and Callus maturation.)
4. The accumulated phenolic compounds was decreased to lower most level when combination of anti-oxidant solution plus P.V.P in the medium .Then ,followed by P.V.P treatment in improving all parameters under study.
5. Supplementation the culture medium with 2.0 mg/L 2,4-D encouraged the highest increase in Callus formation, Callus development and Callus maturation.
6. Adding BAP to the culture medium proved to be the best cytokinin type enhanced all Callus formation parameters specifically at 2.0 mg/L level.
7. Combination treatment (2.0 mg/L 2,4-D plus 0.5 mg/L BAP) showed the best hormonal balance encouraged the largest Callus formation, Callus development and Callus maturation.
1. 2. Callus induction (Callus development):
8.Using Yeast extract at 300 mg/L level enhanced Callus development and maximized number of Somatic embryos, and Callus maturation.
1. 3.Plantlets regeneration:
9. Supplementation the culture medium with 1.0 mg/L NAA (Naphthalene acetic acid) and 0.5mg/L BAP (6-benzylaminopurine) as hormonal balance encouraged production the highest numbers of regenerated Plantlets.
1. 4.Proliferation:
10. Kinetin proved to be the best cytokinin enhanced Growth and Greening parameters while reduced Necrosis. However, using of BAP in the culture medium is superior in increasing proliferation.
11. Adding 2.0 mg/L BAP to the culture medium was effective in increasing Proliferation while the low concentration of BAP (1.0 mg/L) induced the highest Growth and Greening parameters.
1. 5 Rooting:
1. 5 .a.Shoot elongation:
12.Using different concentrations of GA3 induced an adverse effect on the Shoot elongation and Rooting parameters i.e, Necrosis, Shoot elongation, Rooting and Greening.
1. 5 .b. Root formation:
13.Indole-3-butyric acid surpassed NAA in enhancing Rooting parameter while Growth and Greening parameters were maximized when NAA was used.
14.The best Rooting appeared when 2.0 mg/L IBA was added to the culture medium while Growth and Greening were the best when cultured on medium free hormone.
2. Oil content:
15.Adding Yeast extract at 300 mg/L level to the culture medium maximized essential oil percentages to 0.3% and improved oil composition as the percentage of linalool reached to 34.86%,camphor to 17.02%, and β –caryophyllene to 11.96%.
16.Storing Callus for 6 months led to an increase in essential oil percentage to 0.4% and percentage of linalool to39.68% compared with control treatment (26.05%).Also,it reached percentage of β –caryophyllene to 12.07% , camphor to18.60% compared with control treatment.
3.Cytology:
Cytological studies proved that high percentage of similarity was found between Control and (T2) 90.0% ,while the lowest degree (60%) was shown among (T3), followed by (T1 and 88.9%) between Control and storage periods of lavender callus.
Conclusion
Culturing of pre-treated leaf disc of both lavender and thyme with combination of (anti-oxidant solution +P.V.P) and pre-treated with cold treatment for 7 days then, cultured 0n modified MS medium supplemented with either 2.0mg/L 2,4-D 0r 2.0 mg/L BAP maximized Callus formation of lavender but with very low extent in case of thyme which led to terminate further experiments on thyme at this level. On the other hand, addition of combination treatment (2.0 mg/L 2,4-D&0.5 mg/L BAP) increased Callus formation. Moreover, supplementation the culture medium with 300 mg/L Yeast extract improved Callus development . Meanwhile, using combination treatment (1.0 mg/L NAA and 0.5 mg/L BAP) maximized Somatic embryos and plantlets regeneration. Then, addition 2.0 mg/L BAP induced the highest proliferation while supplementing the culture medium with 2.0 mg/L GA3 and 2.0 mg/L IBA enhanced Shoot elongation and Rooting of lavender.
Furthermore, addition of 300 mg/L Yeast extract to the medium as well as storing of callus for 6 months maximized oil percentage and improved chemical composition of lavender matured callus. Storing callus for 6 months decreased similarity up to (60%).