TABLE 1.

Ecological characteristics evaluated on MON 89788 and A3244 in 2004–2006

Study	Characteristic	Evaluation timinga	Evaluation description
Phenotypic Study 1, 2, 3b	Arthropod, disease, abiotic stressors	Recurring, recorded approx. every 4 wk beginning at approx. V2–V4	Qualitative assessment of specific stressors rated on a 0–9 rating scale (0 = no stressor symptoms and 9 = most severe stressor symptoms) but reported by category
Phenotypic 1 & 2c,d	Arthropod abundance	Recurring approx. every 4 wk beginning approx. 4 wk after plants reached V2 stage	Quantitative assessment of arthropods collected
Allelopathic effects	Emergence–lettuce	7 DAP: Shoot tissue evaluation; 9 DAP: Soil medium evaluation	Number of seedlings in each pot with 2 fully unfurled cotyledons
Allelopathic effects	Growth stage (leaf number)–lettuce	3 wk after planting (shoot tissue and soil medium evaluations)	Fully unfurled true leaves (i.e., not cotyledons)
Allelopathic effects	Plant height–lettuce	3 wk after planting (shoot tissue and soil medium evaluations)	Determined by measuring from the soil surface to the end of the longest leaf
Allelopathic effects	Fresh weight–lettuce	3 wk after planting (shoot tissue and soil medium evaluations)	Determined by cutting the plant at the soil surface. The shoot tissue of each plant was weighed within 1 h of harvest
Allelopathic effects	Dry weight–lettuce	3 wk after planting (shoot tissue and soil medium evaluations)	After fresh weight measurements were collected, the shoot tissue samples were oven-dried at approximately 40°C for 7 d, then weighed
Cold tolerance	Plant height	37 DAP: 20 d under either optimal temperature (29°C day/24°C night) or cold (15°C day/8°C night)	Distance from the soil line to the shoot apex
Cold tolerance	Vegetative growth stage	37 DAP: 20 d under either optimal temperature (29°C day/24°C night) or cold (15°C day/8°C night)	Developmental stage assessed by counting the uppermost fully developed trifoliate leaf node (V1 = first trifoliate leaf has unrolled leaves…V(n) = nth trifoliate leaf has unrolled leaves)
Cold tolerance	Vigor	37 DAP: 20 d under either optimal temperature (29°C day/24°C night) or cold (15°C day/8°C night)	Rated on a 0–9 scale, where 0 = dead plant, 1–3 = below average vigor, 4–6 = average vigor, and 7–9 = above average vigor
Cold tolerance	Fresh weight	37 DAP: 20 d under either optimal temperature (29°C day/24°C night) or cold (15°C day/8°C night)	Determined by cutting the plant at the soil surface and immediately weighing above-ground tissue
Cold tolerance	Dry weight	37 DAP: 20 d under either optimal temperature (29°C day/24°C night) or cold (15°C day/8°C night)	After fresh weight measurements were collected, plants were oven-dried at approximately 38°C for 9 d, then weighed
Volunteer potential	Number of emerged plants after winter sowing	6 observations per site, spring through mid-June
Symbiont study	Nodule number	4 and 6 wk after emergence	Nodules were separated from roots for counting
Symbiont study	Nodule dry weight	4 and 6 wk after emergence	Dry weight of nodules separated from roots prior to drying
Symbiont study	Root dry weight	4 and 6 wk after emergence	Dry weight of roots separated from nodules prior to drying
Symbiont study	Shoot dry weight	4 and 6 wk after emergence	Dry weight of material cut off at surface of the potting medium
Symbiont study	Shoot total nitrogen	4 and 6 wk after emergence	After drying and weighing, shoot tissue was ground and sieved. Total nitrogen was determined by combustion using a nitrogen analyzer

^aPhenotypic and Volunteer studies were performed in the field; all others were greenhouse or growth chamber studies. DAP, days after planting. Plant developmental stages are as described in Pedersen (2004).

^bMeasurements at all 27 locations used in these 3 studies (Table S2).

^cIL, MO1, and MO2 sites in Phenotypic Study 1 (Table S2).

^dIA, IN, and NE sites in Phenotypic Study 2 (Table S2).