Performance of Wild and Laboratory-Reared Gypsy Moth (Lepidoptera: Erebidae): A Comparison between Foliage and Artificial Diet

Abstract

The effects of long-term mass rearing of laboratory insects on ecologically relevant traits is an important consideration when applying research conclusions to wild populations or developing management strategies. Laboratory strains of the gypsy moth, Lymantria dispar (L.), an invasive forest pest in North America, have been continuously reared since 1967. Selection on these strains has enhanced a variety of traits, resulting in faster development, shorter diapause, and greater fecundity. As in many mass-reared insects, laboratory strains of the gypsy moth are also reared exclusively on artificial diets that lack much of the phytochemical and nutritional complexity associated with natural foliage. We tested for differences in growth and development of wild gypsy moth populations from across the invasive range in comparison to laboratory strains when reared on artificial diet and a preferred foliage host species, northern red oak (Quercus rubra L.). Overall, caterpillars reared on foliage had higher survival and faster development rates, with smaller differences among populations. When reared on artificial diet, laboratory strains had the highest performance as expected. The response from the wild populations was mixed, with two populations performing poorly on artificial diet and another performing nearly as well as the laboratory strains. Performance on diet was enhanced when larvae received cubed portions changed regularly, as opposed to filled cups. Understanding these relationships between food source and population performance is important for informing studies that examine population comparisons using wild and laboratory-reared strains.

Variation in growth and developmental responses to supraoptimal temperatures near latitudinal range limits of gypsy moth Lymantria dispar (L.), an expanding invasive species

“…The NJSS population has likely never experienced supraoptimal temperatures subsequent to its initial founding, yet it has higher survival at 29 and 31 °C than all other populations, even those from the southern range extent that have historically experienced these temperatures. This relative success may be attributed to NJSS performing better when reared on artificial diet than the wild sourced populations (Grayson et al ., ).…”

“…The thermal performance curve for the laboratory strain of gypsy moth is well characterized, with peak developmental rates occurring at approximately 28 °C (Logan et al ., ). However, recent work reports that there are performance differences between laboratory strain individuals and individuals from wild populations when reared on different diets (Grayson et al ., ). In natural populations, there is the potential to adapt to warmer temperatures as gypsy moth continues to spread south in the U.S.A.; yet, no studies have compared gypsy moth performance across their wide latitudinal range or addressed the potential for local adaptation at the leading edge of the invasive range.…”

Facilitation between invasive herbivores: hemlock woolly adelgid increases gypsy moth preference for and performance on eastern hemlock

“…Because this colony is intended for research, certain selective regimes and control measures have been enacted upon it to maximise the survival and fecundity of the gypsy moths. These include laboratory selection for higher survival and fecundity, and an artificial diet (Frontier Agricultural Sciences, USDA Hamden Formula), which may incidentally select for genotypes that show reduced performance on a natural diet (Grayson et al ., ). However, a comparison of development between gypsy moth larvae from the New Jersey Standard Strain‐APHIS substrain, ‐FS substrain, and three wild populations all reared on a natural diet, found no population‐level differences in male and female pupal weights (Grayson et al ., ).…”

“…These include laboratory selection for higher survival and fecundity, and an artificial diet (Frontier Agricultural Sciences, USDA Hamden Formula), which may incidentally select for genotypes that show reduced performance on a natural diet (Grayson et al ., ). However, a comparison of development between gypsy moth larvae from the New Jersey Standard Strain‐APHIS substrain, ‐FS substrain, and three wild populations all reared on a natural diet, found no population‐level differences in male and female pupal weights (Grayson et al ., ). Additionally, our observation of substantial wild gypsy moth larval herbivory damage to adelgid‐infested field‐grown eastern hemlocks, as well as a confirmed wild gypsy moth larval preference for adelgid‐infested hemlocks mirror results from the laboratory performance assay and further support their ecological relevance.…”

We Should Continue the Half-Century History of Applications of Antisense Oligonucleotides in Medicine, Agriculture and Forestry: A Mini-Review

“…We chose the gypsy moth as the target insect for our investigations because gypsy moth larvae, who cause damage to over 500 plant species, are therefore directly responsible for substantial economic losses. Gypsy moth larvae are voracious feeders, able to consume more than 1 m 2 of foliage per larva during the caterpillar stage [111,112]. During surges in population (outbreaks), which can last 1-3 years, larvae are capable of completely defoliating host trees, after which they move on to cereal crops and even vegetables.…”