The Defense Responses of Eucalyptus to Insect-Feeding and Leaf-Clipping Stresses
Abstract
1. Introduction
2. Materials and Methods
2.1. Test Insects
2.2. Temporal Changes in Eucalyptus Defense Enzyme Activities Induced by Insect-Feeding and Leaf-Clipping Stresses
2.2.1. Protein Content Determination
2.2.2. Peroxidase Activity Assay
2.2.3. Polyphenol Oxidase Activity Assay
2.2.4. Phenylalanine Ammonia-Lyase Activity Assay
2.3. Temporal Changes in Non-Volatile Defense Compound Content in Eucalyptus Induced by Insect-Feeding and Leaf-Clipping Stresses
2.3.1. Salicylic Acid Content Determination
2.3.2. Jasmonic Acid Content Determination
2.3.3. Condensed Tannin Content Determination
2.4. Data Analysis
3. Results
3.1. Effects of Insect-Feeding and Leaf-Clipping Stresses on Defense Enzyme Activity in Eucalyptus Leaves
3.1.1. Protein Content in the Tissue of Eucalyptus Leaves Under Different Treatment
3.1.2. Effects of Insect-Feeding and Leaf-Clipping Stresses on Peroxidase Activity in Eucalyptus Leaves
3.1.3. Effects of Insect-Feeding and Leaf-Clipping Stresses on Polyphenol Oxidase Activity in Eucalyptus Leaves
3.1.4. Effects of Insect-Feeding and Leaf-Clipping Stresses on Phenylalanine Ammonia-Lyase Activity in Eucalyptus Leaves
3.2. Effects of Insect-Feeding and Leaf-Clipping Stresses on the Contents of Defense Compounds in Eucalyptus Leaves
3.2.1. Temporal Changes in Salicylic Acid Content Induced by Insect-Feeding and Leaf-Clipping Stresses
3.2.2. Temporal Changes in Jasmonic Acid Content Induced by Insect-Feeding and Leaf-Clipping Stresses
3.2.3. Temporal Changes in Tannin Content Induced by Insect-Feeding and Leaf-Clipping Stresses
3.3. Principal Component Analysis of the Defense Responses of Eucalyptus Leaves
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
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Chen, C.; Zhang, Z.; Lin, W.; Xu, M.; Lin, Z.; Zheng, K.; Ailiminuer, T.; Wu, Q.; Chen, X.; Chen, H. The Defense Responses of Eucalyptus to Insect-Feeding and Leaf-Clipping Stresses. Life 2026, 16, 604. https://doi.org/10.3390/life16040604
Chen C, Zhang Z, Lin W, Xu M, Lin Z, Zheng K, Ailiminuer T, Wu Q, Chen X, Chen H. The Defense Responses of Eucalyptus to Insect-Feeding and Leaf-Clipping Stresses. Life. 2026; 16(4):604. https://doi.org/10.3390/life16040604
Chicago/Turabian StyleChen, Cong, Zihui Zhang, Wenxin Lin, Meiling Xu, Zhaoyan Lin, Keling Zheng, Tuerxun Ailiminuer, Qijing Wu, Xingyu Chen, and Hua Chen. 2026. "The Defense Responses of Eucalyptus to Insect-Feeding and Leaf-Clipping Stresses" Life 16, no. 4: 604. https://doi.org/10.3390/life16040604
APA StyleChen, C., Zhang, Z., Lin, W., Xu, M., Lin, Z., Zheng, K., Ailiminuer, T., Wu, Q., Chen, X., & Chen, H. (2026). The Defense Responses of Eucalyptus to Insect-Feeding and Leaf-Clipping Stresses. Life, 16(4), 604. https://doi.org/10.3390/life16040604

