Project description:Female adult spongy moths vary in their flight capacity depending upon their origin and subspecies. Asian spongy moth (Lymantria dispar asiatica) females (such as the RM strain here) can fly whereas European spongy moth (Lymantria dispar dispar) females cannot (such as the CT strain here). We hypothesized that the genetic origins of these differences in flight capacity would be reflected in differences in gene expression during metamorphosis (the pupal stage). To test this, we compared the gene expression at days 1, 3, 5, 8, and 11 of pupal development of female pupae from CT and RM strains.
Project description:• Herbivore-induced plant volatiles (HIPVs), in addition to attracting natural enemies of herbivores, can serve a signaling function within plants by acting as wound signals that induce or prime defenses. However, particularly in woody plants, which compounds within HIPV blends are capable of acting as signaling molecules are largely unknown. • Leaves of hybrid poplar (Populus deltoides x nigra) saplings were exposed in vivo to naturally wound-emitted concentrations of the green leaf volatile (GLV) cis-3-hexenyl acetate (z3HAC) and then subsequently fed upon by gypsy moth larvae (Lymantria dispar L.). Volatiles were collected throughout the experiments, and leaf tissue was collected to measure phytohormone levels and expression of defense-related genes. • Relative to controls, z3HAC-exposed leaves had higher levels of jasmonic acid and linolenic acid following gypsy moth feeding. Further, z3HAC primed transcripts of phytohormone signaling (lipoxygenase 1) and direct defense (a Kunitz proteinase inhibitor) genes. These qRT-PCR results were supported by microarray analysis using the AspenDB 7K EST microarray containing ~5400 unique gene models. Moreover, z3HAC also primed the release of herbivore-induced terpene volatiles. • The widespread priming response suggests an adaptive benefit to detecting z3HAC as a wound signal. Thus, woody plants can detect and use z3HAC as a signaling cue to prime defenses before actually experiencing damage. GLVs may therefore have important ecological functions in arboreal ecosystems.