Environ. Biosafety Res.
Volume 3, Number 1, January-March 2004
|Page(s)||5 - 16|
|Published online||15 March 2004|
Movement of coat protein genes from a commercial virus-resistant transgenic squash into a wild relative
Department of Plant Pathology, Cornell University, New York State Agricultural Experiment Station, Geneva, NY 14456, USA
2 Department of Horticultural Sciences, Cornell University, New York State Agricultural Experiment Station, Geneva, NY 14456, USA
Corresponding author: email@example.com
We monitored pollen-mediated transgene dissemination from commercial transgenic squash CZW-3 into its wild relative Cucurbita pepo ssp. ovifera var. texana (C. texana). Transgenic squash CZW-3 expresses the neomycin phosphotransferase II (nptII) gene and the coat protein (CP) genes of Cucumber mosaic virus (CMV), Zucchini yellow mosaic virus (ZYMV), and Watermelon mosaic virus (WMV); thereby, it is resistant to these three aphid-borne viruses. The rate of NPT II and CP transgene introgression increased with overlapping flowering patterns and a high ratio of transgenic F1 hybrids (C. texana × CZW-3) to C. texana. Transgene transfer also readily occurred from transgenic F1 hybrids into C. texana over three generations in field settings where test plants grew sympatrically and viruses were not severely limiting the growth, and fruit and seed production of C. texana. In contrast, introgression of the transgenes into C. texana was not sustained under conditions of high viral disease pressure. As expected, C. texana progeny that acquired the CP transgenes exhibited resistance to CMV, ZYMV, and WMV. This is the first report on transgene dissemination from a transgenic crop that exhibits disease resistance and hybridizes with a wild plant species without loss of fertility.
Key words: Environmental safety / risk assessment / pollen flow / transgenic squash / Cucurbita texana / coat protein gene / Cucumber mosaic virus / Zucchini yellow mosaic virus / Watermelon mosaic virus / neomycin phosphotransferase (NPT) II gene / introgression / enzyme-linked immunosorbent assay / engineered virus resistance
© ISBR, EDP Sciences, 2004