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Ag Data Commons migration begins October 18, 2023

The Ag Data Commons is migrating to a new platform – an institutional portal on Figshare. Starting October 18 the current system will be available for search and download only. Submissions will resume after the launch of our portal on Figshare in November. Stay tuned for details!

Data from: Honeydew associated with four common crop aphid species increases longevity of the parasitoid wasp, Bracon cephi (Hymenoptera: Braconidae)

    Abstract from published manuscript: The absence of sugar resources can be an important factor in limiting the success of parasitoids as biological control agents. Restoring vegetation complexity within agricultural landscapes has thus become a major focus of conservation biological control efforts, with a traditional emphasis on nectar resources. Aphid honeydew is also an important source of sugars that is infrequently considered. We carried out a laboratory experiment to examine the potential effects of honeydew from six different aphid species by crop species combinations on the longevity of Bracon cephi Gahan (Hymenoptera: Braconidae), the most important biological control of the wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), a major pest of wheat in the northern Great Plains of North America. The benefits of honeydew for parasitoid longevity varied significantly among different aphid and crop species, illustrating the complexity of these interactions. However, honeydew produced by four aphid species commonly found in wheat, pea, and canola crops significantly increased the longevity (by two- to threefold) of the parasitoid. The study suggests that honeydew provisioning could be an important mechanism underlying the benefits of crop diversification to support biological control that merits further research.

    Data from: High genetic diversity in the landscape suggests frequent seedling recruitment by Euphorbia virgata Waldst. & Kit. (leafy spurge) in the northern U.S.A.

      Site information and field-collected data from a 1-year 100-site survey of leafy spurge (Euphorbia virgata/esula) populations in the northern U.S. Data include: 1) estimates of leafy spurge density and relative prevalence of ramets versus genets; 2) the abundance and composition of Aphthona species complex biological control agents; 3) presence/absence of two additional biological control agents (Oberea erythrocephala and Hyles euphorbiae).

      Data from: Niche partitioning and coexistence of parasitoids of the same feeding guild introduced for biological control of an invasive forest pest

        The data set is collected to evaluate if two parasitoids (Spathius galinae and Tetrastichus planipennisi), introduced for biocontrol of the invasive emerald ash borer (EAB), Agrilus planipennis, into North America have established niche-partitioning, co-existing populations following their sequential or simultaneous field releases to 12 hard-wood forests located in Midwest and Northeast regions of the United States.

        Data from: Host plant water deficit stress impairs reproduction and development of the galling fly (Parafreutreta regalis), a biological control agent of Cape-ivy (Delairea odorata)

          Data from choice and no-choice tests associated with the paper cited below. Drought leading to water deficit stress is known to reduce performance of galling insects. The shoot tip-galling fly Parafreutreta regalis has been released for biological control of Cape-ivy (Delairea odorata) in California. Lack of moisture during the dry season causes wilting of Cape-ivy shoots, and subsequent reduced host quantity and quality could influence the fly’s ability to multiply and establish. We imposed water deficit stress on potted Cape-ivy plants, then measured the plant’s and insect’s response to water deficit compared to fully-watered plants.

          Data from: Release and establishment of the weevil Mecinus janthiniformis for biological control of Dalmatian toadflax in southern California

            We monitored populations of the stem weevil, Mecinus janthiniformis, the invasive alien weed Dalmatian toadflax (Linaria dalmatica) and other vegetation to document the impact of using M. janthiniformis as a biological control agent of L. dalmatica. Weevils were released in 2008 and again in 2014 after a wild fire. The results document increases and spread of weevil populations, decrease in Dalmatian toadflax and changes in cover of some vegetation classes.