Influences of habitat-level crop diversity on community dynamics of pentatomids and their parasitoids in New Jersey

View the project report

Commodities

• Agronomic: soybeans
• Fruits: peaches

Practices

• Pest Management: biological control

The brown marmorated stink bug (BMSB) is an invasive insect that is a major agricultural pest in the United States and other countries. In the Mid-Atlantic, BMSB reached outbreak levels in 2010 and has caused severe damage to fruit, vegetable, and field crops since. Several native stink bugs persist in agroecosystems as well, and BMSB has altered community dynamics of these species and their natural enemies. For instance, Trissolcus japonicus, a nonnative egg-parasitoid that is closely associated with BMSB in Asia, has established populations in 15 known US states and DC since 2014, and its establishment is likely due to availability of BMSB egg masses. The arrival of T. japonicus has community-wide effects, as the parasitoid also parasitizes other pentatomid eggs and competes with endemic parasitoids for reproductive resources.

In this project, we will evaluate how habitat diversity and background pentatomid abundances influence stink bug-parasitoid food-webs. We will survey four species BMSB and three native stink bugs (two pests and one beneficial) and their associated parasitoids in four different habitat-types in New Jersey—peach-dominated, soybean-dominated, mixed-crop with flowers, and forest. Egg parasitoids will be surveyed via field-deployed sentinel egg masses, and host-parasitoid interactions will be classified as successful (adult parasitoid emergence) and unsuccessful (partially developed parasitoid) parasitism. We will compare parasitoid abundance and species richness and food-web metrics, such as linkage density, to compare control of stink bug pests in different habitats and inform management strategies aimed to maximize ecological pest control.

1. Survey and compare abundances of four pentatomid species—BMSB, BSB, HB, and SSB—in four habitat types in New Jersey—peach-dominated, soybean-dominated, mixed crop, and forest.
2. Assess successful and unsuccessful parasitism and predation of sentinel eggs of BMSB, BSB, HB, and SSB in four habitat types in New Jersey—peach-dominated, soybean-dominated, mixed crop, and forest. Identify parasitoid species using species identification keys and molecular techniques such as DNA barcoding.
   • Compare abundance and diversity of the parasitoid complex across habitats
   • Compare incidence of parasitism in eggs between pentatomid species and habitat type
   • Calculate food-web complexity matrices across habitats and compare them between habitat types