Regulation of Calcium on Peanut Photosynthesis Under Low Night Temperature Stress

The effects of different levels of CaCl2 on photosynthesis under low night temperature (8 degrees C) stress in peanuts were studied in order to find out the appropriate concentration of Ca2+ through the artificial climate chamber potted culture test. The results indicated that Ca2+, by means of improving the stomatal conductivity of peanut leaves under low night temperature stress, may mitigate the decline of photosynthetic rate in the peanut leaves. The regulation with 15 mmol L-1 CaCl2 (Ca15) was the most effective, compared with other treatments. Subsequently, the improvement of Ca2+ on peanut photosynthesis under low night temperature stress was validated further through spraying with Ca15, Ca2+ chelator (ethylene glycol bis(2-aminoethyl) tetraacetic acid; EGTA) and calmodulin antagonists (trifluonerazine; TFP). And CaM (Ca2+-modulin) played an important role in the nutritional signal transduction for Ca2+ mitigating photosynthesis limitations in peanuts under low night temperature stress.