Lipid provisioning in the eggs of an extreme dietary generalist

Parents can provide care to their offspring to increase their offspring’s
chance of survival. There are various types of parental care across insect
taxa, one of which is maternal investment. Lipids, the most energy-dense
of macronutrients, are considered a good estimate of maternal investment
in insects. However, it is not clear how different environments, such as
host plants, can impact provisioning, especially for dietary generalists
that feed on an array of plant species with varying quality. Using an
extreme dietary generalist, fall webworm (FW, Hyphantria cunea), we
investigated if females provision different amounts of lipids into their
eggs depending on the diet they fed upon as larvae. We measured the lipid
content of FW egg clusters from parents reared on seven host plant species
of varying quality. We found that parental host plants influenced egg
provisioning, such that provisioning depends on host plant but also
increases most for parents reared on low-quality diets. Additionally, we
found that female parents with heavier pupal mass produced egg clusters
with greater lipids per egg. Our results provide evidence that egg
provisioning can depend on the parental environment and suggest that the
use of low-quality host plants by generalist herbivores may be partially
overcome via maternal investment.