NaCl胁迫下AM真菌对棉花生长和叶片保护酶系统的影响

Effects of AM fungi on the growth and protective enzymes of cotton under NaCl stress

利用盆栽实验研究了 Na Cl胁迫条件下 AM真菌对棉花生长和叶片保护酶系统的影响。结果表明 :在土壤中加入 0、0 .1%、0 .2 %、0 .3%浓度 Na Cl条件下 ,Na Cl胁迫对 AM真菌的接种效果有显著影响。接种 AM真菌提高了棉花根系菌根侵染率 ,增加了棉株的生物产量 ,以 0～ 0 .2 % Na Cl浓度时 AM真菌接种效果最好。 AM真菌对棉株生理参数和保护酶活性的影响因生育期和 Na Cl浓度不同而异 ,现蕾期和低盐浓度 (0～ 0 .1% )下叶片叶绿素含量明显增加 ;中高盐水平 (0 .2 %～ 0 .3% )和生育后期叶片可溶性蛋白质含量和 SOD、POD、CAT等保护酶活性显著提高 ,MDA含量明显降低 ;棉株 K、Ca、Mg含量因植株部位和盐浓度不同而变化。 AM真菌增强宿主植物的耐盐性可能源于促进宿主根系对土壤矿质元素吸收的直接作用和改善植物体内离子平衡和生理代谢活动。

The effects of AM fungi on the growth and protective enzymes in cotton plants inoculated Glomus mosseae and Glomus caledonium under salt-caused stress conditions was studied at the levels of 0,0.1%,0.2%,0.3% NaCl added to the soil for the potted plant. The results showed that application amount of NaCl significantly influenced the growth of cotton plants and inoculation effect of AM fungi. After inoculation mycorrhizal infection rate was promoted, and total dry weights and output of cotton were increased, which was the best under applying 0～0.2% NaCl density. Leaf syn-pigment significantly increased in the period of showing buds and 0～0.1% NaCl density. The content of soluble protein and activity of protective enzyme, such as SOD, POD and CAT increased in the pregnant later period and 0.2%～0.3% NaCl density. The content of K, Ca and Mg varied with the position of plant and NaCl density. It could be concluded that the mechanism of AM fungi strengthening the salt tolerance of cotton plants may be the direct role of AM fungal hyphal contribution to soil minerals uptake in mycorrhizal plant, and the indirect role of AM fungi improved mycorrhizal plant interior ionic balance and the physiological metabolic activity and enhanced the activity of protective enzymes.