壳聚糖对毒死蜱胁迫下菠菜生理生化指标的缓解作用

以菠菜（Spinacia olerac ea L.）为材料,在露地栽培条件下研究了不同浓度壳聚糖（0、50、100、200mg·L-1）对毒死蜱胁迫下菠菜超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）、O2-·产生速率、过氧化氢（H2O2）、丙二醛（MDA）、脯氨酸、可溶性糖积累的缓解作用。结果表明,壳聚糖对毒死蜱胁迫下菠菜抗氧化酶活性及相关生理指标起到了缓解作用,其中低浓度壳聚糖（50、100mg·L-1）的缓解作用更为明显。喷施低浓度壳聚糖后,能提高菠菜的SOD活性,降低O2-·产生速率以及MDA、脯氨酸和H2O2的积累,从而缓解毒死蜱对菠菜的胁迫作用。与毒死蜱胁迫相比,壳聚糖能将毒死蜱胁迫下的抗氧化酶活性及相关生理指标较早的恢复到对照水平,主要体现在SOD活性以及MDA、可溶性糖、脯氨酸和H2O2积累的变化上。就壳聚糖的缓解作用而言,壳聚糖对菠菜SOD活性、O2-·产生速率以及MDA、脯氨酸和H2O2积累的缓解作用较大,而对POD、CAT、APX活性和可溶性糖积累的缓解作用较小。

Alleviation Effects of Spraying Chitosan on Spinach Seedling Physiological Indexes Under Chloryrifos Stress

In recent years,more attentions have been paid to the chemical pesticide application and its influences on crops.It is well documented that the use of organophosphorus pesticides in vegetables could significantly change some physiological metabolisms,and then growth of vegetables.In the present study we investigated effects of spraying chitosan with different concentration on the activities of SOD,POD,CAT,and APX,O2-·producing rate,and the content of H2O2,MDA,proline,and soluble sugar in spinach seedlings under chloryrifos stress in the open-field.Results showed that spraying with lower chitosan concentrations（50,100 mg·L-1）alleviated damages caused by chloryrifos stress more effectively than that of with other concentration.After spraying with lower concentrations,the SOD activity was increased,O2-·producing rate,MDA,proline,and H2O2 content in spinach seedlings were reduced.The activities of SOD,and POD,the content of H2O2,MDA,proline,and soluble sugar in chitosan spraying treatments could be recovered more earlier from the chlorpyrifos stress to the control level.The effects of spraying chitosan on the activity of SOD,O2-·producing rate,the content of H2O2,proline,and MDA in spinach were more effectively than on the activities of POD,CAT,and APX,and the soluble sugar content.