Surface Warfare: Plant Structural Defenses Challenge Caterpillar Feeding
Herbivorous insects, especially caterpillars, exert significant selection pressure on their host plants, as they exclusively depend on them for their growth and development. To counter this extensive loss of plant biomass that significantly affects their growth, development, and fitness, plants have evolved a suite of structural and chemical defenses. Structural defenses, including surface waxes and trichomes, are primarily present at the leaf surface where caterpillars tend to initiate their feeding after hatching. In this chapter, we argue that these structural defenses play an equally important role to their counterpart, chemical defenses, which have traditionally received disproportionately more attention. We discuss various roles played by waxes and trichomes as examples of surface structural defenses, their chemical composition, and morphological features that assist in combating herbivory in various caterpillar-host plant systems. We then use trichomes as a model to discuss the specificity and diversity of plant-herbivore interactions and to examine the counter defense strategies employed by caterpillars to thwart these defenses. Finally, we discuss current developments and future avenues bridging natural history and mechanistic underpinnings in our understanding of structural defenses and their ongoing surface war against caterpillars.
Kaur, I., Watts, S., Raya, C., Raya, J., Kariyat, R. (2022). Surface Warfare: Plant Structural Defenses Challenge Caterpillar Feeding. In: Marquis, R.J., Koptur, S. (eds) Caterpillars in the Middle. Fascinating Life Sciences. Springer, Cham. https://doi.org/10.1007/978-3-030-86688-4_3
Caterpillars in the Middle. Fascinating Life Sciences