In June 2012, CBS News reported that a federal investigation was underway after a herd of cattle had died of after eating genetically modified grass which had begun producing cyanide. CBS soon issued a correction: 'As originally published, this story referred to Tifton 85 grass as a genetically-modified product, which is incorrect; it is actually a hybrid of Bermuda grass.' (1)
A 2005 study indicates Tifton 85 had been genetically modified:
'A facile, cultivar-specific regeneration protocol is required to pursue genetic improvement of Tifton 85 for incorporating insect resistance into this valuable forage crop.' (2)
'However, its high susceptibility to the insect pest fall armyworm [Spodoptera frugiperda (J.E. Smith)] warrants genetic engineering approaches to produce pest resistant germplasm. Traditional breeding methods for Tifton 85 are impossible because of the sterile nature of all hybrid bermudagrass cultivars.' (2)
However, the Tifton 85 had reportedly been there 15 years.
In 2004, a New Scientist article reported that wind blown pollen from GM grass had pollinated other grasses up to 21 kilometres away, with extensive genetic contamination 2 km downwind of the experimental plots. (3)
The parents of Tifton 85 are a nlemfuensis and a dactylon, different species of the Cynodon genus. Nlemfuensis, the main parent, is a stargrass (often Hypoxis).
Dactylon, from which came the cold tolerance gene, is known to produce a non lethal amount of cyanide. (4)
'Tifton 85 (Burton et al., 1993) is a hybrid of Tifton 68 (Burton and Monson, 1984) and PI 290884 (G# 32 and 33). Tifton 85 was released based on yield and ruminant digestibility characteristics similar to Tifton 68 but with much greater cold tolerance (from PI 290884). The relatively high genetic distance between Tifton 85 and PI 290884 supports the observed wide phenotypic difference except for cold tolerance.' (5)
After the cattle death:
'Tifton 85 is a cross between a bermudagrass [Cynodon dactylon, specifically cv. Tift 292 (an armyworm resistant plant introduction in the USDA-ARS collection)] and a closely related Cynodon species called stargrass [Cynodon nlemfuensis, specifically cv. Tifton 68 (highly digestible, but cold susceptible). Crosses were made by placing inflorescences (the day before pollen shed) of each parent in a beaker of water.' (6)
- CBS News. Grass linked to Texas cattle deaths
- Embryogenic callus induction and regeneration in a pentaploid hybrid bermudagrass cv. Tifton 85. Mukesh Jain et al.
- New Scientist. Wind carries GM pollen record distances. Fred Pearce.
- Cyanogenesis in savanna grasses. Peter Hayward, Marcus Hohl
- Genetic Variability of a Forage Bermudagrass Core Collection.William F. Anderson et al.
- Media Distortions about Tifton 85. Dr. Dennis W. Hancock
- Varieties of Bermudagrass. Soil, Crop and More Information