Date of Award
Master of Science
Agricultural and Biosystems Engineering
Industrial and Agricultural Technology
Gretchen A. Mosher
The open air growing environment for corn (Zea mays L.) makes it impossible to maintain genetic purity of 100%. Much debate has characterized the discussion on acceptable tolerance levels for adventitious presence to ensure coexistence between genetically modified and non-genetically modified crops. This research analyzes nine scenarios to test field, handling, and elevator-based segregation capabilities in a commodity system. Using stochastic models to model individual factors that contribute to adventitious presence in commodity maize including: impure seed, isolation distance, equipment cleanout, and elevator handling practices, Monte Carlo simulation was used to calculate the cumulative amount of adventitious presence for each scenario.
Output values from 50,000 iterations for each scenario were used to assess the feasibility of meeting tolerance levels of 0.9%, 1.5%, and 3.0% genetic impurity. The modeling suggests that a 0.9% tolerance level is not feasible in most cases, with feasibility ranging from 0.0% to 49.8% across the nine scenarios. The tolerance levels of 1.5% and 3.0% are feasible in certain cases, however, with feasibility ranging from 3.0% to 94.7% at a tolerance level of 1.5% and feasibility ranging from 54.4% to 100.0% at a tolerance level of 3.0%. Sensitivity analysis found that isolation distance was the most significant factor in five out of the nine scenarios, elevator handling practices was most significant in three out of the nine scenarios, and seed purity was the most significant in one of the nine scenarios.
Chad Joseph Dolphin
Dolphin, Chad Joseph, "Segregation strategies for non-gm corn: Improving effectiveness through an analytical modeling approach" (2019). Graduate Theses and Dissertations. 17003.