干旱胁迫对沙地云杉生态型保护酶活性的影响

Study on the Effect of Drought Stress on the Activity of Protective Enzyme of Three Ecotypes of Picea mongolica

通过不同干旱胁迫处理,测定了3种生态型(紫果型、绿果型和红果型)沙地云杉叶片和根部的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(ASP)、过氧化物酶(POD)的活性。结果表明:在叶片中,无论哪种生态型,SOD活性先上升,后下降;紫果型沙地云杉CAT活性一直上升,但变化幅度不大,红果型和绿果型则先升后降;ASP和POD活性变化趋势一致,紫果型一直以较大幅度增加,红果型和绿果型开始迅速增加,而后又迅速下降。在根部,酶活性的变化与叶片中基本一致。因此得知,紫果型沙地云杉抗旱能力最强,绿果型最弱。

Picea mongolica is an endemic arbor species in Inner Mongolia and grows only in the eastern marginal zone of Hunshandark Sandland where the entironment is extremely fragile. After doing different drought stress treatments, in this study the values of activity of protective enzymes including superoxide dismutase （SOD）, catalase （CAT）, ascorbate peroxidase （ASP） and peroxidase （POD） in leaves and roots of three ecotypes （f. purpurea, f. viridis andf. rubra） ofPicea mongolica are measured. The results show that the SOD activity in leaves of the three ecotypes of Picea mongolica increases firstly, and then decreases. The CAT activity in leaves off. purpurea increases all along, but that off. rubra andf. viridis increases firstly, and then decreases. The change trend of ASP activity accords with that of POD activity, the ASP and POD activities in leaves off. purpurea increase significantly, but those off. rubra andf. viridis increase rapidly at the beginning, and then decrease rapidly. The change trends of protective enzymes in roots accord with that in leaves. purpurea is the highest It can be confirmed that the drought resistance off. , and that off. viridis is the lowest. The study results can provide the theoretical basis for researching and understanding the formation mechanism and drought resistance of the ecotypes of Picea mongolica.