Theoretical and Applied Genetics (2002) 104, 797-803

M.K. Butterfield, J.E. Irvine, M. Valdez Garza and T.E. Mirkov (2002)
Inheritance and segregation of virus and herbicide resistance transgenes in sugarcane
Theoretical and Applied Genetics 104 (5), 797-803
Abstract: Transgenic sugarcane parents containing multiple copies of herbicide resistance (bar) and Sorghum mosaic virus (SrMV) resistance (hut) genes were crossed with non-transgenic sugarcane varieties. Segregation of the transgenes in the progeny was determined using Southern blot analysis; herbicide resistance and SrMV resistance were assessed using bioassays. The segregation data were used to infer linkage relationships between transgenes in the parent plants. In two of the parents, all transgene insertions were linked in one position in the genome, although some recombination between insertion events did occur. In the third parent, insertion had occurred in two independent, unlinked loci. Analysis of progeny of this parent indicated that rearrangement or mutation occurred in both loci, resulting in non-parental transgene DNA fragments in some progeny. Most transgenic progeny containing the bar gene showed resistance to herbicide. SrMV inoculation indicated that a fairly high proportion of the transgenic progeny showed susceptibility. As the post-transcriptional gene silencing mechanism responsible for the virus resistance phenotype may be reset during meiosis, phenotypic screening of older plants may be a more reliable indication of virus resistance than screening young seedlings. This is the first report of transgene segregation in sugarcane, and we have demonstrated that transgenic sugarcane parents showing stable inheritance of transgenes can be effectively used in breeding programs.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): T. Erik Mirkov

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Sorghum mosaic virus	Sugarcane (Saccharum officinarum)