Figure 6.

Acquired and basal thermotolerance analyses. A, Seedlings were heated to 37.5°C for 1 h, returned to 22°C for 2 d, heated to 44.5°C for 1 h, and then allowed to recover for 7 d. B, Quantification of seedling chlorophyll contents after the 7-d recovery as shown in A. Group I did not undergo any heat treatment. Group II was only acclimated at 37.5°C for 1 h and did not undergo the 44.5°C 1-h heat shock. C, Seedlings 7-d-old were directly heated at 44.5°C for the amount of time indicated. After the heat shock treatments, seedlings were allowed to recover for 7 d. D, Quantification of chlorophyll contents of seedlings that went through the 30-min heat shock treatment in C. [See online article for color version of this figure.]