IDENTIFICATION OF SOME VARIETIES OF PALM TREES USING BARCODE GENE

Abstract

In last decade, date palm has been considerable undergo to intensive molecular and cytogenetic studies. In recent years a new technique ‘DNA barcoding’ was suggested to identify animal and plant species. The consortium for the Barcode of Life's Plant Working Group selected some markers from chloroplast genes as Ribulose-1,5-Biophosphate Carboxylase/Oxygenase Large Subunit (rbcL), maturase K (matK), RNA Polymerase β subunit (rpoB), Acetyl-coenzyme A carboxylase carboxyl transferase β subunit (accd) and Internal Transcripted spacer (ITS) from nuclear genome. In the present study, six different varieties of dates, viz. Hayani, Sakkoty, Gondila, Bartamoda, Malkaby and Amhaat were sequenced for rbcL, matK, hypothetical chloroplast reading frame 5 (ycf5), an intergenic spacer a region of non-coding DNA between two genes (psbA-trnH) and ITS genes for being used as barcode in date palm. Bioinformatics tools were used to establish its potential as a DNA barcoding of Egyptian date palm varieties. One variety (Bartamoda) has been used for studying the somaclonal variation during tissue culture technique and chromosomal aberrations in microproagated plant and seeds of mother plant, and analyzing its karyotype. The results showed that the nuclear ITS marker was failed to amplify well, and suggested that it is not existed in the palm genome. While tested chloroplast matK, rbcL, and ycf5 markers have successfully amplified products and were more informative than the psbA-trnH chloroplast DNA marker, which was failed to amplify and resulted in distinct double bands in all cultivars, except Gondila. Sequencing and phylogenetic trees were constructed on the basis of the matK, rbcL, and ycf5 markers, and the results suggested that the matK, rbcL, and ycf5 can be used for determining the levels of genetic divergence and for identification of Egyptian date palm. The cytological studies showed that there were high similarity among the micropropagated plantlets and seeds of mother plant.