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A separate petition should be submitted for each category/phenotype combination. For example, a petition for Coleopteran insect-resistant potatoes or PVY-

resistant potatoes should be submitted separately. However, when a single plant contains more than one phenotype modification, submit only one petition. For example, one petition should be submitted for potatoes

that are both PVY and PVX resistant.

Below is an example of an acceptable summary of a test of BT cotton pollen on a beneficial nontarget organism.

Springborn Laboratories, Inc. (Wareham, MA) conducted a 48- hour static-renewal test with Bt cotton pollen (homozygous for the cryIA(b) gene) and isogenic pollen on Daphnia magna, according to EPA Guideline No. 72-2. Details of these studies have been submitted in the registration package to the USEPA (see appendix). Daphnids were <24 hours old at the time of study initiation. For the definitive test, dose levels of 19, 32, 54, 90, and 150 mg pollen/L (containing 5.87 mg CryIA(b)/g pollen) were employed. These levels are a hundredfold higher than the LC50 for target insects. In addition, isogenic controls at the same pollen concentrations as the treatment group were tested along with a negative control group. Each test or control concentration consisted of two replicates of 10 daphnids each for a total of 20 daphnids/ concentration or control group. Daphnids were exposed for 48 hours with complete renewal of the test solutions after 24 hours.

Mean survival was 100 percent for each of the transgenic, isogenic, and negative control groups. All daphnids in the transgenic, isogenic, and negative control groups appeared normal during the study. No immobilization or sublethal signs of toxicity were observed. The only effect noted was a decrease in dissolved oxygen in the higher test concentrations of both pollen groups. Dissolved oxygen concentrations were inversely related to the concentration of pollen tested and were similar in equivalent concentrations of the transgenic and isogenic groups. The decrease in dissolved oxygen had no effect on the survival of the daphnids. Higher concentrations for both types of pollen were cloudy and some daphnids were observed to be coated with pollen. At 48 hours, the EC50 based on immobilization was >150 mg pollen/L for both the transgenic and isogenic groups. Based on these results, the NOEC was 150 mg transgenic or isogenic pollen/L (the highest concentration tested).

SAMPLE PETITIONHerbicide-Tolerant Plants

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