Free gossypol Total gossypol Flavonoids
0.75a 1.0a 1.84a
0.75a 1.0a 1.76a
Certain plants have minute quantities of known toxicants which may adversely impact nontarget organisms and beneficial insects; e.g., tomatine in tomatoes, cucurbitin in cucurbits, gossypol in cotton etc. If such plants are recipients of transgenes, the applicant should provide information as to whether the level of toxicants is altered. If the plant produces no known toxicant, the applicant should state so and provide the reference to support the claim. Plant toxins can be assessed by the tests and criteria that plant breeders traditionally use in the crop. In some instances, this may be done qualitatively, e.g. taste testing of cucurbits.
Table 2—Mean toxicant content in cottonseed of transformed and nontransformed cultivars grown at four sites
Free and total gossypol and flavonoids are given as percent of kernel weight assayed according to the methods of Cherry (1983) and Hedin (1988) respectively. Within each column, means followed by the same letter are not significantly different according to the Newman-Kreuls multiple range test.
G. Characteristics of Glyphosate-Tolerant Cotton
We determined that the minimum level of glyphosate needed to control morning glory, cotton’s major weed pest, was 8 oz/acre. At this level, the glyphosate-tolerant cotton was undamaged by the herbicide. This concentration is generally also adequate for the control of Morningglory, Common cocklebur, Pigweed, Johnsongrass, Nutsedges and Bermudagrass which are all important weeds in cotton cultivation.
Glyphosate-tolerant cotton is still susceptible to two other broad-spectrum herbicides, sulfonylurea and bromoxynil, as is its progenitor cultivar. Thus, the transformed cultivar can be eliminated using herbicides with a different mode of action from glyphosate if that is desired.
SAMPLE PETITION—Herbicide-Tolerant Plants