DOI: 10.5061/dryad.dncjsxmbj
title: Egg adhesion of the codling moth <em>Cydia pomonella</em> L. (Lepidoptera, Tortricidae) to synthetic substrates

description: Previous studies on Cydia pomonella eggs have demonstrated reliable egg
 adhesion to the leaves and fruits of various apple cultivars. In contrast
 to biological substrates, this study focuses on standardized synthetic
 substrates to measure egg pull-off forces and determine adhesive strength,
 allowing for an unbiased comparison with other, previously studied
 organisms. Analyses using various microscopy techniques and white light
 interferometry at the interface between egg adhesive secretion and
 substrate helped to interpret the data. The results showed that codling
 moth eggs adhered more strongly to smooth, high-surface-energy substrates
 (such as hydrophilic glass) compared to low-surface-energy ones, achieving
 adhesive strengths of 138 kPa on hydrophilic surfaces and
 22 kPa on hydrophobic ones. Correspondingly, the surface wetting
 by the adhesive egg secretion and egg contact area were both larger on
 hydrophilic than on hydrophobic glass, measuring 1.8 and 1.4 mm2,
 respectively. The adhesive layer was found to be remarkably thin,
 measuring only 10 nm on hydrophilic glass and 153 nm on
 hydrophobic glass. Egg adhesion to hydrophobic glass aligns with the
 conditions found on the waxy surfaces of apple host plants, although
 mechanical interlocking can be ignored on the smooth glass. The pull-off
 forces required to detach eggs from substrates corresponded to 313,053
 times the egg weight on hydrophobic glass and 2,442,220 times the egg
 weight on hydrophilic glass. We suggest that in an ecological context, the
 optimal egg adhesion, which can resist environmental impacts, is more
 crucial than the maximum bond strength. The consistency, surface wetting,
 speed of the hardening process, and adhesive potential of the egg
 secretion may inspire further developments in codling moth control and the
 synthesis of biomimetic adhesives.
description: # Egg adhesion of the codling moth *Cydia pomonella* L. (Lepidoptera,
 Tortricidae) to synthetic substrates Dataset DOI:
 [10.5061/dryad.dncjsxmbj](10.5061/dryad.dncjsxmbj) ## Description of the
 data and file structure **- ROUGH DATA -**
 **Al_Bitar_et_al._2025_rough_data_egg_pull-off_force_on_glass.csv** Column
 A. run number: number of test runs. Column B. glass surface: hydrophilic
 and hydrophobic glass surface = substrate. Column C. (pre)load [mN] Column
 D. pull-off force [mN] required to remove an egg from the substrate:
 pull-off force required to detach 24-h aged eggs from hydrophobic and
 hydrophilic glass.
 **Al_Bitar_et_al._2025_rough_data_egg_pull-off_force_on_plastic.csv**
 Column A. run number: number of test runs. Column B. egg age: age of egg
 after oviposition. Column C. pull-off force [mN] required to remove an egg
 from the substrate: pull-off forces required to detach &lt; 24-hours and
 &gt; 24-hours aged eggs from plastic foil.
 **Al_Bitar_et_al._2025_rough_data_fecundity.csv** Column A. surface
 roughness [µm]: Spurr resin surfaces with asperity sizes (roughnesses) of
 0.3, 1, 3, 9, 12 µm used for ovipostion substrates. Column B. repetition:
 four samples counted per each substrate. Column C. eggs per female/12 h
 [number of eggs]: number of eggs per female *Cydia pomonella* laid within
 12 h on rough Spurr resin surfaces; the larger the surface asperity size,
 the rougher the substrate.
 **Al_Bitar_et_al._2025_rough_data_glass_contact_angle.csv** Column A.
 fluid: Type of fluid used for contact angle measurements of 1-µl droplets.
 Column B. repetition: three droplets measured per each substrate type.
 Column C. glass surface: hydrophilic and hydrophobic glass surface =
 substrate. Column D. contact angles of 1-µl fluid droplets [°]: contact
 angles of 1-µl fluid droplets on the glass substrates; see protocols for
 contact angle and surface energy measurements on apple surfaces (Al Bitar
 et al. 2012, 2014 in the manuscript’s reference list).                   
     **Al_Bitar_et_al._2025_rough_data_glass_surface_free_energy.csv**
 Column A. glass surface physico-chemical properties: physico-chemical
 properties (contact angles [°] and free surface energy [mN/m] with
 dispersed and polar compounds [mN/m]) of the hydrophilic and hydrophobic
 glass substrates; derived from ‚Al Bitar et al. 2025_rough data_glass
 contact angle.csv‘. Column B. hydrophilic: hydrophilic glass. Column C.
 hydrophobic: hydrophobic glass. ## Code/software csv files obtained from
 Excel software ## Access information Other publicly accessible locations
 of the data: * Supplement to the Publication on the webpage of Journal of
 Applied Entomoloty Data was derived from the following sources: *
 experimental approaches described in the corresponding article: Al Bitar
 (2025) Egg adhesion of the codling moth *Cydia pomonella* L. (Lepidoptera,
 Tortricidae) to synthetic substrates. Journal of Applied Entomology