Pruning from spheroidal to cubic canopy induced aphid outbreak by altering the plant performance in Box tree

Backgrounds: Plant-animal interactions comprise the fundamental relationships of ecological research, and are sensitive to environmental change. However, The effects of pruning on animal-plant interactions have rarely been studied. Methods: We conducted field experiments to examine the impact of artificially-pruned shapes (e.g. cubic and spheroidal canopy) on the performance of the Box tree and the resulting aphid abundance at three sites; on a university campus, at a road green belt, and in a residential area. The differences of aphid abundance and plant morphology were determined with ANOVAs and paired-sample tests. Relationships between the investigated parameters were detected with simple regression and structural equation modelResult: Abundance was higher in plants with a cubic canopy than with a spheroidal canopy. Plants with a cubic canopy had lower leaf dry mass content and inflorescence numbers, but greater fresh twig length than the plants with a spheroidal canopy. The aphid abundance was negatively correlated with the leaf dry mass content and inflorescence numbers, and positively correlated with the fresh twig length. Conclusion: Our findings have proven that pruning shape can significantly affect the abundance of herbivores on the pruned plants. The results can provide data support for human actives can alter plant performance, and thereby to change insect preference.