AUTHOR=Maheshwari Priti , Kovalchuk Igor 

TITLE=Agrobacterium-Mediated Stable Genetic Transformation of Populus angustifolia and Populus balsamifera

JOURNAL=Frontiers in Plant Science

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2016.00296

DOI=10.3389/fpls.2016.00296

ISSN=1664-462X

ABSTRACT=<p>The present study demonstrates <italic>Agrobacterium tumefaciens-</italic>mediated stable genetic transformation of two species of poplar – <italic>Populus angustifolia</italic> and <italic>Populus balsamifera</italic>. The binary vector pCAMBIA-Npro-long-Luc containing the luciferase reporter gene was used to transform stem internode and axillary bud explants. Putative transformants were regenerated on selection-free medium using our previously established <italic>in vitro</italic> regeneration method. Explant type, genotype, effect of pre-culture, <italic>Agrobacterium</italic> concentration, a time period of infection and varying periods of co-culture with bacteria were tested for the transformation frequency. The highest frequency of transformation was obtained with stem internode explants pre-cultured for 2 days, infected with <italic>Agrobacterium</italic> culture at the concentration of OD<sub>600</sub> = 0.5 for 10 min and co-cultivated with <italic>Agrobacterium</italic> for 48 h. Out of the two genotypes tested, <italic>P. balsamifera</italic> exhibited a higher transformation rate in comparison to <italic>P. angustifolia</italic>. The primary transformants that exhibited luciferase activity in a bioluminescence assay under the CCD camera when subjected to polymerase chain reaction and Southern blot analysis revealed a stable single-copy integration of <italic>luc</italic> in their genomes. The reported protocol is highly reproducible and can be applied to other species of poplar; it will also be useful for future genetic engineering of one of the most important families of woody plants for sustainable development.</p>