Genetic transformation of apple for increasing its resistance to fungal diseases

Abstract

The aim was to establish an efficient and practical reproducible approach of genetic transformation for apple cvs. 'Golden Delicious', 'Royal Gala' and  'MM111', 'M26' rootstocks for improving their fungal resistance using genetic engineering techniques. Putative transgenic shoots could be obtained on MS media with B5 Vitamins, 5.0 mg l^-1 BAP, or 2.0 mg l^-1 TDZ with 0.2 mg l^-1  NAA in the presence of the selection agent "PPT" at 3.0-5.0 mgl^-1. Transgenic clones of the apples studied have been obtained and confirmed by selection on the media containing the selection agent "PPT" and by PCR analysis using the suitable primers in all clones obtained for the presence of the selection" bar gene and the gene-of-interest "g2PS1". Results of DNA sequence analysis of the transgenic plants also proved the successful transformation and had 97 to 99% sequence homology with the gerbera hybrida mRNA for 2-pyrone synthase g2ps1 gene (accession no. Z38097.2). These transgenic clones were multiplied further and rooted in vitro in the presence of the selection agent 'PPT'. Rooted transgenic plantlets were successfully acclimatized and are being kept under-containment conditions according to the biosafety by-law in Syria to evaluate their performance for fungal resistance.