| 摘 要： | We examined the changes of chemical composition and protein conformation in Arabidopsis leaves by Fourier transform–infrared (FT-IR) spectrometry Arabidopsis under 50 mmol/L NaCl salt and ?0.5 mPa polyethylene glycols 8000 (PEG 8000) drought stress during the early stages of growth. We primarily analyzed the absorption band areas in the 1,745 cm-1 (ester), 1,600–1,700 cm-1 (amide I), and 1,100 cm-1 (carbohydrate) changes under salt stress and drought stress within 24 hours. The results showed that ester content declined at the beginning and then increased steadily during 24 hours of drought stress. But under salt stress, it declined steadily, and it was about 40 percent of the control after 24 hours. The protein synthesis increased by 25 percent after one hour of salt stress and then reached about 85 percent of the control after 24 hours. Under drought stress, the protein synthesis decreased and reached a minimal level at the 4-hr time point; it then recovered to the control level at the 24-hr point. The patterns of the accumulation of carbohydrates in the 1,100 cm-1 band areas resembled that of amide I band changes under drought stress and salt stress. Analyzing the ratio A1,627cm-1/A1,658cm-1 under drought stress revealed that the leaves’ entire protein structure maintained a higher-level ordered form than did those under salt stress. Thus our results indicate the existence of different strategies of the Arabidopsis adaptation to salt stress and drought stress.
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