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The spotted lanternfly Lycorma delicatula White (Hemiptera: Fulgoridae) is a polyphagous insect pest that invaded the United States in 2014, in Berks County, Pennsylvania. It has since spread to several northeastern states and poses a significant threat to northeastern grape production. Most studied species of Hemiptera are known to communicate intraspecifically using some form of substrate-borne vibrational signals, although such behavior has not yet been reported in L. delicatula. This report demonstrates that adult and fourth-instar L. delicatula were attracted towards broadcasts of 60-Hz vibroacoustic stimuli directed to a laboratory arena and test substrate, which suggests that both adults and fourth instar nymphs can perceive and respond to vibrational stimuli., (Published by Oxford University Press on behalf of Entomological Society of America 2022.)

Studies were conducted from 2015 to 2018 to evaluate spotted lanternfly (SLF) distribution and developmental suitability of different plant species in the U.S. Tree bands on 283 trees spanning 33 species captured 21,006 SLF in 2 yr. More SLF per tree were trapped on tree-of-heaven Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae) than on other species, on average, and most adults were captured on tree-of-heaven. Frequency of detection of adult SLF was higher on tree-of-heaven than on other species but was actually equal or lower on tree-of-heaven than on all other species combined for younger SLF stages in 2015. An enclosed choice test between tree-of-heaven and black walnut Juglans nigra L. (Fagales: Juglandaceae) revealed nymphs showed little consistent preference, whereas adults consistently and significantly preferred tree-of-heaven. No-choice field sleeve studies evaluated SLF survivorship on 26 host plant species in 17 families. Ten plant species supported SLF for an average of ≥45 d, with the rest unable to support SLF for >30 d. Eight species were able to support development from first instar to adult: black walnut, chinaberry Melia azedarach L. (Sapindales: Meliaceae), oriental bittersweet Celastrus orbiculatus Thunb. (Celastrales: Celastraceae), tree-of-heaven, hops Humulus lupulus L. (Rosales: Cannabaceae), sawtooth oak Quercus acutissima Carruthers (Fagales: Fagaceae), butternut Juglans cinerea L, and tulip tree Liriodendron tulipifiera L. (Magnoliales: Magnoliaceae). The ability of SLF to develop to adult on hosts other than tree-of-heaven may impact pest management decisions., (Published by Oxford University Press on behalf of Entomological Society of America 2020.)

Host plant volatiles play a key role in mediating plant-herbivore interactions. How an array of host plant volatiles guides host preference and attraction in the invasive polyphagous Lycorma delicatula (White), the spotted lanternfly (SLF), is largely unknown. A pernicious phloem feeder, SLF feeds on over 70 species of plants, some with high economic impact. To aid the development of detection and monitoring tools for SLF, we used a two-choice olfactometer to compare 14 host plant species for attraction, first to a blank control, and then to their preferred host Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae), tree-of-heaven. SLF were significantly attracted to seven host plants compared to a blank control, but no host plant was more attractive than tree-of-heaven. We then used electroantennographic detection (EAD) to screen select host plants for EAD active compounds, hypothesizing that EAD-active plant volatiles act as kairomones and mediate SLF attraction to host plants. Out of 43 unique antennal responses, 18 compounds were identified and tested individually for attraction in a two-choice olfactometer against a blank control and then against methyl salicylate, the current best attractant. Eleven compounds were significantly attractive, and one, sulcatone, was more attractive than methyl salicylate. Blends of kairomones were then tested for attraction, revealing five blends that were significantly more attractive than methyl salicylate, and could be developed into lures for field testing. The presence of these kairomones in volatile profiles of 17 plant species is described. These findings support the hypothesis that the identified volatiles act as kairomones and function in attraction to host plants., (Published by Oxford University Press on behalf of Entomological Society of America 2020.)

The spotted lanternfly, Lycorma delicatula (White), is an invasive phloem feeder recently introduced into North America that attacks a broad range of woody plants. When feeding in large numbers, they can seriously damage or kill a tree. Their preferred host is the invasive tree-of-heaven, Ailanthus altissima Swingle (Sapindales: Simaroubaceae), but they are serious pests of grape, Vitis vinifera L. (Vitales: Vitaceae) and a number of other commercially important host plants. Volatile collections were conducted on tree-of-heaven and grape, and the most abundant compounds from these plants present in samples and indicated in the literature were tested for attraction in the laboratory and field. Three compounds, methyl salicylate, (Z)-3-hexenol, and (E,E)-α-farnesene, were found to be highly attractive in laboratory behavioral bioassays. Methyl salicylate was attractive to all stages of L. delicatula, whereas the youngest nymphs were not as attracted to (Z)-3-hexenol or (E,E)-α-farnesene in laboratory bioassays. When comparing individual compounds, methyl salicylate attracted the most L. delicatula. Methyl salicylate lures in the field produced a two- to four-fold increase in captures compared with unbaited controls, and field testing also revealed a significant positive dose response. Of the several types of sticky bands tested, Web-Cote Industries sticky bands were found to be most efficient at trapping L. delicatula adults and nymphs., (Published by Oxford University Press on behalf of Entomological Society of America 2019.)

Three cryptic species in the Euwallacea fornicatus species complex were reared in laboratory colonies and investigated for the presence of pheromones. Collections of volatiles from combinations of diet, fungus, beetles, and galleries from polyphagous shot hole borer ( Euwallacea sp. #1) revealed the presence of 2-heneicosanone and 2-tricosanone only in the presence of beetles, regardless of sex. Subsequent examination of volatiles from the other two species, tea shot hole borer ( Euwallacea sp. #2) and Kuroshio shot hole borer ( Euwallacea sp. #5), revealed these two ketones were present in all three species but in different ratios. In dual choice olfactometer behavioral bioassays, mature mated females were strongly attracted to a synthetic binary blend of ketones matching their own natural ratios. However, females in each species were repelled by ketone blends in ratios corresponding to the other two species. Males of each species responded similarly to females when presented with ratios matching their own or the other two species. The presence of these compounds in the three beetle species, in ratios unique to each species, and their strong species-specific attraction and repellency, suggests they are pheromones. The ecological function of these pheromones is discussed. In addition to the pheromones, the previously known attractant (1 S ,4 R )- p -menth-2-en-1-ol (also known as quercivorol) was discovered in the presence of the fungal symbionts, but not in association with the beetles. Quercivorol was tested in a dual-choice olfactometer and was strongly attractive to all three species. This evidence suggests quercivorol functions as a kairomone for members of the E. fornicatus species complex, likely produced by the symbiotic fungi., Competing Interests: The authors declare there are no competing interests.