Attractants from Bartlett pear for codling moth, Cydia pomonella (L.), larvae

Area of Science:

• * Chemical Ecology
• * Entomology
• * Pest Management

Background:

• * Codling moth (CM), *Cydia pomonella*, is a significant pest in apple and walnut orchards.
• * Understanding insect attractants (kairomones) is crucial for developing effective pest management strategies.
• * Volatile compounds from host plants often act as cues for insect behavior.

Purpose of the Study:

• * To identify volatile compounds from ripe Bartlett pears (*Pyrus communis* L.) that attract codling moth (CM) neonate larvae.
• * To compare the attractiveness of identified pear volatiles with known CM attractants like (E,E)-alpha-farnesene.
• * To evaluate the potential application of these compounds in CM monitoring and control.

Main Methods:

• * Head-space analysis of ripe Bartlett pear volatiles.
• * Olfactometer bioassays (Petri-plate, Y-tube, straight-tube) using CM neonate larvae.
• * Testing responses to alkyl esters of (2E,4Z)-2,4-decadienoic acid and other pear volatiles.

Main Results:

• * Ethyl and methyl (2E,4Z)-2,4-decadienoate esters from pear headspace significantly attracted CM neonate larvae.
• * Ethyl (2E,4Z)-2,4-decadienoate demonstrated higher attractiveness at lower dosages compared to (E,E)-alpha-farnesene.
• * Other tested pear volatiles, including acetates and (E)-beta-ocimene, did not attract CM neonates.

Conclusions:

• * Ethyl and methyl (2E,4Z)-2,4-decadienoate are potent kairomones for codling moth neonates.
• * Ethyl (2E,4Z)-2,4-decadienoate is a more effective attractant than previously known compounds at lower concentrations.
• * These pear-derived esters hold promise for developing novel monitoring and control tools for codling moth in agricultural settings.