Technical Abstract: In our lab, transgene silencing is a major barrier to efficient use of genetic transformation in sugarcane. Recently the Ac-Ds transposon system from maize was developed as a tool for functional genomic analysis(1) and transformation of barley(2). A bar gene introduced by particle bombardment underwent silencing (as scored by leaf-painting with Basta) in 77% of F-2 lines. The original transgene locus consisted of multiple, rearranged copies of three transgenes, typical of bombardment gene introduction. When single-copy bar lines were produced by Ac mediated transposition and segregated away from the original multi-copy locus, silencing did not occur in any F-2 lines. Because this system requires at least one sexual cross, it is not suitable for use in commercial sugarcane varieties or in other crops which are highly heterozygous. We now report excision transposition from Ac-Ds plasmids introduced to sugarcane cells. A vector system has been developed to allow direct plasmid to chromosome transposition in monocot cells, which will allow single-copy transposition lines to be produced in a single generation, without sexual cross.