Abstract
Calcium (Ca) influence on chilling resistance of grafting eggplant seedlings were studied in a hydroponic system. Under the calcium sufficient treatment, the activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) in grafting seedlings at 5°C were all obviously higher than those of calcium deficiency, peaking at 36 h, 24 h, and 24 h chilling stress, respectively. Several parameters of cellular membrane fluidity, such as content of unsaturated fatty acid (UFA), the ratio of UFA to SFA (U/S), index of UFA (IUFA) also distinctively increased. The contents of malondialdehyde (MDA) and saturated fatty acid (SFA) were lower than those of calcium deficiency. This study suggests that the variation of parameters mentioned above might be caused by cellular calcium levels. Calcium content was potentially the main reason that grafting seedlings had higher chilling resistance than own-root seedlings. Calcium appears to play an important role in increasing chilling resistance of grafting eggplant seedlings.
Acknowledgments
We thank the Hebei Nature Science Foundation of China (399125) for financial support. We also thank Shang Qingmao, Liu Su, and Dong Huiru in Institute of vegetable and flowers, Chinese academy of agricultural science who provide excellent technical assistance.