Expression of engineered wheat dwarf virus in seed-derived embryos.

Delivery of DNA into dry and viable embryos of wheat by imbibition in DNA solution was detected by monitoring the transient expression of chimeric genes. The gene expression vectors used comprise of a neomycin phosphotransferase II (NPT II) reporter gene, under the control of various promoters or as part of a cloned plant virus genome. The genome of wheat dwarf virus (WDV), a monopartite Gemini virus of gramineae, has been used to amplify the NPT II gene in embryos of wheat, thereby leading to high levels of transient expression. Constructions were designed which permitted NPT II expression only if inter- or intramolecular recombination had occurred. [ABSTRACT FROM AUTHOR]