Table I.

Survival rates of transgenic plants under different stress conditions

CBF4-Overexpressing LinesSurvival1-aTotal1-bSurvival1-c
%
Freezing tolerance (nonacclimated)1-d
 Control11691
 L10448552
 L48293583
 L24444100
Freezing tolerance (cold acclimated)1-e
 Control42202
 L10509155
 L48152854
 L2738289
Drought tolerance1-f
 Control31812
 L10449845
 L4812314187
  • F1-a  No. of survival plants.

  • F1-b  Total no. of plants used in each assay.

  • F1-c  Percentage of survival plants.

  • F1-d  Two-week-old plants grown on petri dishes at 22°C and then frozen at −10°C for 20 h.  

  • F1-e  Two-week-old plants grown on petri dishes at 22°C, transferred to 4°C for 4 d, and then frozen at −15°C for 20 h.

  • F1-f Two-week-old soil-grown plants withheld water for 9 d, rewatered, and scored 4 d later. Plants were considered dead if all the leaves were brown and there was no regrowth 4 d after rewatering. Water loss during the drought period was similar for all pots independent of the plant size (data not shown).