PAG-V: W82 - TRANSGENIC VIRUS RESISTANT SUGARCANE

Plant & Animal Genome V Conference

Town & Country Hotel, San Diego, CA, January 12-16, 1997.

W82

TRANSGENIC VIRUS RESISTANT SUGARCANE

MIRKOV, T. ERIK(1), Zhong nan Yang(1), Ivan Ingelbrecht(1), James E. Irvine(2)
1. Texas A&M Agricultural Experiment Station, Department of Plant Pathology and Microbiology, 2415 East Hwy. 83, Weslaco, TX, 78596
2. Texas A&M Agricultural Experiment Station, Department of Soil and Crop Sciences, 2415 East Hwy. 83, Weslaco, TX, 78596

Sugarcane mosaic virus (SCMV) is the most widespread virus disease affecting sugarcane production throughout the world. Towards controlling this group of plant viruses by a genetic engineering approach, we established a collection of 7 strains of sugarcane mosaic virus currently causing disease in sugarcane throughout the world. This includes SCMV strains A, B, D,and E, and the sorghum mosaic (SrMV) strains H, I, and M. Cloned cDNAs containing the coat protein coding region of the genome have been obtained and sequenced for each of these strains. We have produced chimeric constructs made by fusion of untranslatable or antisense forms of the coat protein gene of strain H with the maize ubiquitin promoter. These constructs were used in biolistic co-transformation experiments using the bar gene or the nptII gene as the selectable marker. Plants regenerating roots on selection media were screened for the presence of the transgenes, and we have identified more than 500 plants in which the coat protein gene has been introduced. These plants were screened for resistance by repeated inoculations. Several lines have been inoculated up to six times with strain H, and remain virus free. These same lines also show resistance to the closely related SrMV strains I and M, but not to the distantly related SCMV strains A, D, and E. Initial studies on the molecular basis for this resistance will be discussed.