Transgenic poplar (Populus davidiana×P. bolleana Loucne) expressing dsRNA of insect chitinase gene: lines identification and resistance assay.

Poplar is a valuable tree species that is distributed all over the world. However, many insect pests infest poplar trees and have caused significant damage. To control poplar pests, we transformed a poplar species, Populus davidiana × P. bolleana Loucne, with the dsRNA of the chitinase gene of a poplar defoliator, Clostera anastomosis (Linnaeus) (Lepidoptera: Notodontidae), employing an Agrobaterium-mediated approach. The transgenic plant has been identified by cloning the T-DNA flanking sequences using TAIL-PCR and quantifying the expression of the dsRNA using qPCR. The toxicity assay of the transgenic poplar lines was carried out by feeding the target insect species (C. anastomosis). The results showed that, in C. anastomosis, the activity of chitinase was significantly decreased, consistent with the expression on mRNA levels, and the larval mortality was significantly increased. These results suggested that the transgenic poplar of dsRNA could be used for pest control.