NaCl胁迫对甜高粱幼苗抗性酶活性的影响

【研究目的】研究了不同浓度盐胁迫下甜高粱幼苗的抗性酶的活性及MDA和可溶性蛋白的含量。【方法】甜高粱幼苗采用水培的方法，设了3个盐梯度，1个对照。【结果】随着NaCl胁迫的加剧（当NaCl浓度大于50 mmol•L-1时）甜高粱幼苗膜脂过氧化程度不断加大，膜系统受到破坏；膜保护酶（POD，SOD，CAT，APX）活性降低，200 mmol•L-1 NaCl处理的酶活下降最大，100 mmol•L-1 NaCl处理次之，使体内酶促和非酶促防御系统均遭到破坏，活性氧含量增加对幼苗产生毒害。其中，100 mmol•L-1 NaCl处理后膜脂过氧化程度较轻，膜系统受害程度也轻于200 mmol•L-1 NaCl处理。【结论】轻度盐胁迫（当NaCl浓度是50 mmol•L-1）时，由于抗性酶的作用，活性氧对膜系统没有产生破坏作用。随着盐浓度的增加，抗性酶的活性降低，活性氧的含量不断增加，膜系统受破坏程度也不断加大。

The Effect of NaCl-stressed on Resistance Enzymes Activity in Sweet Sorghum Seedlings

【OBJECTIVE】The resistance enzymes activity,MDA and dissoluvable protein contents effects of different degree salt-stressed on sweet sorghum seedlings was discussed in the paper. 【METHOD】Sweet sorghum seedlings were cultrued in the water, we seted up three salt degrees,and one CK.【RESULTS】Above 50 mmol•L-1 NaCl resulted in membrane lipid per-oxidation, and membrane system is destroys,the action of POD,SOD,CAT and APX declined.Enzyme action of 200 mmol•L-1 NaCl treatments has the largest descendence.100mmol•L-1NaCl treatments are less than 200 mmol•L-1 NaCl treatments. 【CONCLUSION】In the light salt-stressed(when NaCl concentration was 50 mmol•L-1 ),active oxygen did not destroy the membrane system,as a result of resistance enzymes.By the incressing of salt concentration, resistance enzymes activity declined, active oxygen content arised,and the destroy degree of membrane system incressed too.