Why is it difficult to wash aphids off from superhydrophobic kale?

@article{Damle2016WhyII,
  title={Why is it difficult to wash aphids off from superhydrophobic kale?},
  author={Viraj G. Damle and R. Scott Linder and Xiaoda Sun and Nicholas Kemme and Lucas C. Majure and Konrad Rykaczewski},
  journal={Bioinspiration \& Biomimetics},
  year={2016},
  volume={11}
}
Many varieties of the cabbage family have leaves covered with superhydrophobic epicuticular wax, which provides them with self-cleaning characteristics. Since the wax also lowers insect adhesion, rinsing of the leaves with water should be an effective way of removing the insects. Conversely, we report that superhydrophobicity of tuscan kale increases resistance of aphids to hydrodynamic removal. The exterior surface of the insects is also superhydrophobic and acts as an extension of the leaf’s… 
1 Citations

Role of Scale Wettability on Rain-Harvesting Behavior in a Desert-Dwelling Rattlesnake

It is shown that the dorsal scales of the rattlesnake aid in water collection by providing a highly sticky, hydrophobic surface, which pins the impacting water droplets, and this high pinning characteristic stems from surface nanotexture made of shallow, labyrinth-like channels.

References

SHOWING 1-10 OF 69 REFERENCES

How aphids lose their marbles

The physical and physiological significance of the secreted powdery wax, used by aphids to efficiently parcel and transport their own excrement, is reported on.

Slippery surfaces of pitcher plants: Nepenthes wax crystals minimize insect attachment via microscopic surface roughness

It is demonstrated that microscopic roughness alone is sufficient to minimize insect attachment and a theoretical model shows that surface roughness within a certain length scale will prevent adhesion by being too rough for adhesive pads but not rough enough for claws.

Attachment to Plant Surface Waxes by an Insect Predator1

The study opens the way for using a similar approach to understand attachment by insects to waxy plant surfaces by examining how EW micromorphology and chemical composition of Brassica oleracea influence attachment by the predatory beetle, Hippodamia convergens.

Plant penetration by feeding aphids (Hemiptera, Aphidoidea): a review.

The factors responsible for determining the host-plants and feeding sites of aphids, and the various probing activities (the role of the labium, stylet insertion, surface saliva deposition, the

Insect aquaplaning: Nepenthes pitcher plants capture prey with the peristome, a fully wettable water-lubricated anisotropic surface.

  • H. BohnW. Federle
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2004
It is demonstrated that the two factors preventing insect attachment to the peristome, i.e., water lubrication and anisotropic surface topography, are effective against different attachment structures of the insect tarsus.

The cabbage aphid: a walking mustard oil bomb

It is demonstrated that aphid myrosinase expression in head/thoracic muscle starts during embryonic development and protein levels continue to accumulate after the nymphs are born, indicating the apparent lack of an effective chemical defence system in adult winged aphids.

Aphids secrete watery saliva into plant tissues from the onset of stylet penetration

It is suggested that watery saliva is secreted by aphid feeding from the onset of stylet penetration, similar to the number ejected by aphids during longer probes including a single intracellular puncture.

Predation, behavior, and attachment by Chrysoperla plorabunda larvae on Brassica oleracea with different surface waxblooms

The results show that reduction in waxbloom can substantially affect the mobility and effectiveness of this generalist predator.
...