Jump to Main Content
The Rooting of Stem Cuttings and the Stability of <i>uidA</i> Gene Expression in Generative and Vegetative Progeny of Transgenic Pear Rootstock in the Field
- Lebedev, Vadim
- Plants 2019 v.8 no.8
- Pyrus, adventitious roots, beta-glucuronidase, environmental factors, fruit trees, gene expression, herbicide resistance, introns, models, pears, progeny, rooting, rootstocks, seedlings, summer, transgenes, transgenic plants, vegetative propagation, woody plants
- Adventitious rooting plays an important role in the commercial vegetative propagation of trees. Adventitious root formation is a complex biological process, but knowledge of the possible unintended effects induced by both the integration/expression of transgenes and in vitro conditions on the rooting is limited. The long-term stability of transgene expression is important both for original transformants of woody plants and its progeny. In this study, we used field-grown pear rootstock GP217 trees transformed with the reporter ß-glucuronidase (uidA) genes with and without intron and re-transformed with the herbicide resistance bar gene as model systems. We assessed the unintended effects on rooting of pear semi-hardwood cuttings and evaluated the stability of transgene expression in progeny produced by generative (seedlings) and vegetative (grafting, cutting) means up to four years. Our investigation revealed that: (1) The single and repeated transformations of clonal pear rootstocks did not result in unintended effects on adventitious root formation in cuttings; (2) stability of the transgene expression was confirmed on both generative and vegetative progeny, and no silenced transgenic plants were detected; (3) yearly variation in the gene expressions was observed and expression levels were decreased in extremely hot and dry summer; (4) the intron enhanced the expression of uidA gene in pear plants approximately two-fold compared to gene without intron. The current study provides useful information on transgene expression in progeny of fruit trees under natural environmental conditions.