Apricot (Prunus armeniaca L.)

Abstract

A protocol for Agrobacterium -mediated stable transformation of whole leaf explants of the apricot (Prunus armeniaca) cultivars ‘Helena’ and ‘Canino’ is described. Regenerated buds were selected using a two-step selection strategy with paromomycin sulfate and transferred to bud multiplication medium 1 week after they were detected for optimal survival. After buds were transferred to bud multiplication medium, antibiotic was changed to kanamycin and concentration increased gradually at each transfer to fresh medium in order to eliminate possible escapes and chimeras. Transformation effi ciency, based on PCR analysis of individual putative transformed shoots from independent lines, was 5.6 %. Green and healthy buds, surviving high kanamycin concentration, were transferred to shoot multiplication medium where they elongated in shoots and proliferated. Elongated transgenic shoots were rooted in a medium containing 70 μM kanamycin. Rooted plants were acclimatized following standard procedures. This constitutes the only transformation protocol described for apricot clonal tissues and one of the few of Prunus.