الفهرس 
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Abstract
The experiments were carried out during the years from 2010 to 2014 at Tissue Culture and Germplasm Conservation Research Lab. Hort. Res. Inst., Agric. Res. Center, Giza, Egypt, to investigate some factors that affecting propagation and production of biocompounds such as quercetin and kaempferol from different explant types of Moringa oleifera Lam. trees using tissue culture techniques. The results obtained from micropropagation of moringa experiments showed that Clorox at 10% for 15 min and mercuric chloride (MC) at 0.1 % for 15 min significantly gave the lowest contamination and the highest survival percentages of stem nodal explants. The lowest contamination and survival percentages were observed with shoot tip explants exposed to 0.1 % mercuric chloride for 7 min. MS medium gave the highest significant number and length of proliferated shoots/explant compared with WPM and B5 media. The highest multiplication rates were achieved using modified MS medium supplemented with 30 g/L sugar, 1.0 mg/L BAP. Repeating subculture up to 3 times increased average number and length of proliferated shoots. The highest rooting percentage and average root number and length were achieved on 3/4 strength MS medium. As for the effect of PGR on rooting stage, using NAA at 2.0 mg/L with 3/4 MS gave the highest rooting percentage. Rooted plantlets were successfully acclimated on mixture of peat moss: sand: vermiculite at 1:1:1 v/v.
As for callus induction, data proved that the highest callus formation percentage was recorded for leaf explants taken from in vitro grown microshoots cultured on MS medium provided with 2,4-D at 2.0 mg/L. The callus growth (accumulative fresh weight) increased with increasing period of incubation and the most favorable conditions were MS medium supplemented with 2.0 mg/L 2,4-D plus 2.0 mg/L kin followed by4.0 mg/L 2,4-D plus 2.0 mg/L kin. Results on biocompounds produced from in vitro callus cultures cleared that the most favorable conditions for callus growth (fresh and dry weight) was that callus cultured on MS medium supplemented with 2.0 mg/L 2,4-D plus 2.0 mg/L kin and incubated under 35°C compared with the other treatments under investigation (UV, microwave and incubation temperature). HPLC analysis indicated that quercetin was detected in a very small percent in leaves of mother tree and increased in callus cultured into medium containing 2.0 mg/L 2,4-D plus 2.0 mg/L kin incubated at 35 and 25°C. While, kaempferol could not be detected in all treatments under study or mother tree except callus culture of 4.0 mg/L 2,4-D plus 2.0 mg/L kin exposed to 100 and 200 w microwave for 10 and 20 sec. Also 30 w of UV-C for 30 min induced callus culture of 2.0 mg/L 2,4-D plus 2.0 mg/L kin to produce kampferol. Antimicrobial activity was studied for all extracts of callus exposed to plant growth regulators, incubation temperature, UV and microwave treatments as well as extracts of leaves and seeds of mother tree, greenhouse seedlings and in vitro shoots. The extracts were tested against two fungi and three bacterial species.
Erwinia amylovora and Staphylococcus aureus were more sensitive to leaves and seeds extracts of mother tree, respectively. While, Salmonella typhis was strongly affected by extract of callus cultured on medium contained 2.0 mg/L kin plus 4.0 mg/L 2,4-D and microwaved at 200 W for 10 sec. Microwave induced callus cultured on medium contained 2.0 mg/L 2,4-D plus 2.0 mg/L kin to produce antifungal substances, using extract of callus exposed to microwave irradiation at 100 W for 10 sec. recorded the largest inhibition zone of Aspergillus niger. Whereas, applying the extract of callus exposed to microwave irradiation at 200 W for 20 sec. recorded the largest inhibition zone for Penicellium digitatum.