Essential Oil Trunk Injection Into Orchard Trees: Consequences on the Performance and Preference of Hemipteran Pests

Area of Science:

• Agricultural Science
• Entomology
• Plant Pathology

Background:

• Conventional pesticide application in orchards leads to significant off-target contamination.
• Trunk injection offers a targeted pesticide delivery method, reducing risks to beneficial organisms and human health.
• Essential oils are explored as eco-friendly alternatives to synthetic pesticides due to their diverse biological activities.

Purpose of the Study:

• To assess the efficacy of cinnamon essential oil trunk injection against key apple and pear pests.
• To evaluate the impact on pest feeding behavior (preference) and life history traits (performance).
• To determine the duration of the essential oil's effect on pests.

Main Methods:

• Cinnamon essential oil emulsion was injected into the trunks of apple and pear trees.
• The study monitored the colonization, feeding behavior, and performance of apple aphids (Dysaphis plantaginea) and pear psyllids (Cacopsylla pyri).
• Comparison between injected trees and control groups was performed to quantify effects.

Main Results:

• Trunk injection of essential oil significantly altered hemipteran pest colonization of host plants.
• Apple aphid feeding on phloem sap was reduced, leading to starvation, while pear psyllid mortality appeared to be due to intoxication.
• Observed changes in pest preference and performance indicate a significant impact of the treatment.

Conclusions:

• Cinnamon essential oil trunk injection demonstrates potential as a targeted pest management strategy in orchards.
• The method affects different pests through distinct mechanisms, including starvation and direct intoxication.
• Further field trials are necessary to confirm the practical effectiveness of this green approach for orchard pest control.