钙对柠檬试管苗生长和一些与抗寒性相关指标的影响

Effects of calcium on the growth of lemon tissue culture seedlings and some physiological and biochemical index related to cold-resistance

不同处理培养柠檬试管苗,高钙培养基能促进试管苗的生长,抑制顶端自枯现象;而EGTA、TFP处理的试管苗,生长受到明显抑制,顶端自枯现象严重,但TFP处理的试管苗能促进根的生长。随着胁迫温度降低,不同处理的试管苗蛋白质含量变化趋势不同,SOD、POD活性都呈先升后降的趋势;随低温胁迫时间延长,可溶性蛋白质含量、SOD、POD活性都呈先升后降的趋势,MDA含量逐渐增加。低温胁迫下,高钙试管苗的蛋白质含量、SOD活性都明显高于其他处理、而MDA含量低于其他处理。结果表明,钙能提高低温胁迫下柠檬试管苗的可溶性蛋白质的含量,增强SOD的活性,降低MDA的含量,从而提高其抗寒性。

Lemon （Citrus limon Ourm） seedlings were cultured on 4 kinds of media with different Ca^2＋ concentration. The results illustrated that the higher calcium content in the media could accelerate the growth of culture seedlings and restrain its top perishing. In contrast, the seedlings cultured in the media with EGTA or TFP, which inhibited the activity of calcium or calmodulin, had lower growth speed, the twig was also badly died back. But with TFP treatment, the growth of the seedling roots could be accelerated. While the stress temperature was declining, the activity of SOD and POD increased first, and then decreased. But the content of protein varied differently among the different treatments. With the prolonged stress period, the soluble protein content, the activity of SOD and POD all increased first, and then dropped, however MDA content was increasing. Under low temperature stress, the content of soluble protein and the activity of SOD of culture seedlings with higher calcium were higher than that of other treatment, while the content of MDA of the seedling with higher calcium was the lowest. Those results proved that calcium could increase the content of soluble protein, strengthen the activity of SOD and reduce MDA content under low temperature stress condition. It was suggested that calcium may strengthen lemon cold-resistance.