الفهرس 
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Abstract
Immature female inflorescences are promising materials for use as explants for the tissue culture of date palm. Four different hormone balances of MS media were used in this study during the four micropropagation stages; starting media (SM), maturation media (MM), multiplication media (PM) and rooting media (RM)to micropropagate three elite date palm varieties, Amri, Magdoul and Barhy using the immature female inflorescences as explant. The highest percentage of callus induction in all the varieties studied was obtained on the SM1 (9 µM 2,4-D + 5.7 µM IAA + 10 µM NAA). Culturing on the MM1 (4.5 µM 2,4-D + 9.8 µM 2-iP + 1.5 AC) allowed us to obtain the best value in terms of callus weight. After culturing on the PM1 (4.4 µM BA + 9.8 µM 2-iP) produced the highest numbers of somatic embryos and shoots. The explants on RM2 (0.5 µM NAA + 1.25 µM IBA + 3 g AC) showed the highest root numbers and root lengths, while the highest shoot length was achieved on RM3 (0.5 µM NAA + 0.5 µM IBA + 3 g AC). The Amri variety presented the best response among the three varieties in all parameters, followed by the Magdoul and Barhy varieties. In all the stages of micropropagation, the analysis of variance revealed highly significant variations among varieties and culture media, and a significant difference in the number of roots during the rooting stage. In contrast showed non-significant differences in the interaction between varieties and culture media, except for shoot length in the rooting stage. The results also reveal the broad sense heritability ranging from low to high for the measured parameters. It can be concluded that the immature female inflorescences can be used as a productive explant source for successful date palm micropropagation using the SM1, MM1, PM1 and RM2 culture media.The molecular profiling was performed by the inter-simple sequence repeats-polymerase chain reaction (ISSR-PCR) tool. Genomic DNA was extracted from young leaves and the PCR reactions were performed using ten primers for the ISSR-PCR marker. A total of 49 loci were produced by the PCR reactions, 38 of which were polymorphic while 11 were monomorphic. The polymorphism revealed by ISSR-PCR ranged from 33.33% to 100%. The cluster analyses based on both morphological data and molecular profiles grouped the three date palm varieties into two groups (I, II). Cluster I comprised the Barhy variety and cluster II included Magdoul and Amri varieties. The study concluded that the success of date palm micropropagation not only depends on the concentrations of growth regulators, but also on their types. Also, the study concluded that the ISSR marker reproduced reliable banding patterns to assess the genetic polymorphism among date palm varieties that are consider the cornerstone for the genetic improvement.