FIGURE 1.

Differential physiological responses of SLH and ZH12 peanut cultivars to cold stress. (A,B) Effects of low temperature on germination rates of the two peanut cultivars. For cold treatment, seeds were immersed in distilled water for 4 h, and then transferred to petri dishes at 2°C for 72 h in the dark, and, finally, returned to normal temperature (28°C) for additional 3 days for germination. The controls were continuously germinated at 28°C for 3 days. SLH (CT), the cold-tolerance cultivar; ZH12 (CS), the cold-susceptible cultivar. The level of O₂^– (C), H₂O₂ (D), and malondialdehyde [MDA, (E)] of peanut seedlings in response to chilling stress. Error bars represent the SD of the means of three biological replications. *An asterisk indicates significant difference between the two cultivars as determined by the Student’s T-test (*p < 0.05; **p < 0.01).