钙对低温胁迫下木薯抗寒相关生理指标的影响

Effects of Ca^(2+) on Cold-resistance Related Physiological Indexes in Cassava under Chilling Stress

以华南8号木薯为试验材料,将生长一致的木薯幼苗用0、10、20、30、40、50 mmol/L等6个梯度的Ca2+进行处理后,对其进行4℃低温胁迫,测定抗寒相关生理指标。结果表明:在20 mmol/L外源Ca2+的作用下,木薯的各项抗寒生理指标较优,膜伤害率、膜脂过氧化产物MDA(丙二醛)含量降低,而保护酶SOD(超氧化物酶)和POD(过氧化物酶)、可溶性糖、可溶性蛋白、游离脯氨酸含量上升,幼苗抗寒性提升效果较明显。Ca2+浓度过高反而产生"毒害"作用,不利于其抗寒性增强。

SC8, a cultivar of cassava, was used as the experiment material in this research. The cassava seedlings, which were at the same growth status, irrigated with six different concentrations of 0, 10, 20, 30, 40, 50 mmol/L Ca2＋, were treated under 4℃ chilling stress. Cold-resistance related physiological indices were determined. The results showed that, cold-resistance related physiological indices of cassava seedlings treated with 20 mmol/L extraneous Ca2＋ were better than others. It could significantly reduce conductivity increase amplitude and malondialdehyde （MDA） content, while significantly enhance the activities of protective enzyme, superoxide dismutase （SOD） and peroxidase （POD）, increase the content of soluble sugar, soluble protein and free proline. However, there would be a negative effect to the hardiness of cassava seedlings when the concentration of Ca2＋ was too high.