Improving Adventitious Shoot Regeneration and Transient Agrobacterium -Mediated Transformation of Apricot (Prunus armeniaca L.) Hypocotyl Sections.

The improvement of previously described protocols for the regeneration of shoots from 'Canino' mature seed hypocotyl slices has been accomplished. The effects of different factors such as the part of the hypocotyl used, vacuum-infiltration, 2,4-Dichlorophenoxyacetic acid pulse, vacuum-infiltration and sonication on regeneration and transient transformation were analyzed. When the three slices obtained from the hypocotyls were evaluated separately on regeneration medium, the highest percentages of regenerating explants were achieved in the part close to the epicotyl and in the central part. On the other hand, sonication of the explants for 30 s followed by vacuum-infiltration during Agrobacterium infection for 20 min allowed for an increase in the transformation events. The application of these modifications to the procedure increased the regeneration efficiencies, and transient transformation events and may reduce the frequency of failed experiments. An efficient regeneration/transformation protocol could facilitate its use as a biotechnological technique for apricot breeding. [ABSTRACT FROM AUTHOR]