Table I.

Freezing tolerance (EL₅₀ values in °C) for nonacclimated and cold-acclimated control and CBF-expressing transgenic B. napus plants^a

Plants	Nonacclimated	Cold Acclimated
Control	−2.1 ± 0.34 (10)	−8.1 ± 0.42 (8)
CBF expressing	−4.7 ± 0.40 (23)	−12.7 ± 0.52 (12)

^a EL₅₀ values were calculated using combined data from individual nonacclimated or cold-acclimated control and CBF-expressing plants (no. of plants used are indicated in parentheses). All values were significantly different from each other (P < 0.001) as determined by ANOVA. Nonacclimated control plants used were: wild type (2), vector-23 (2), vector-161 (4), vector-163 (1), and vector-165 (1). Nonacclimated CBF-expressing plants used were: CBF1-9 (1), CBF1-10 (3), CBF1-26 (3), CBF2-45 (1), CBF2-53 (2), CBF2-65 (3), CBF3-25 (2), CBF3-87 (2), CBF3-108 (1), CBF3-129 (1), and CBF3-145 (3). Cold-acclimated control plants used were: wild type (2), vector-23 (1), vector-161 (3), vector-163 (1), and vector-165 (1). Cold-acclimated CBF-expressing plants used were: CBF1-9 (1), CBF1-10 (2), CBF1-26 (2), CBF2-45 (1); CBF2-53 (1); CBF2-65 (1); CBF3-25 (1); CBF3-87 (1); CBF3-145 (2).