Location: Sunflower and Plant Biology ResearchTitle: Pest potential of Neotephritis finalis (Loew) on Silphium integrifolium Michx., Silphium perfoliatum L., and interspecific hybrids
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/12/2019
Publication Date: 2/14/2020
Citation: Reinert, S., Hulke, B.S., Prasifka, J.R. 2020. Pest potential of Neotephritis finalis (Loew) on Silphium integrifolium Michx., Silphium perfoliatum L., and interspecific hybrids. Agronomy Journal. 112:1462-1465. https://doi.org/10.1002/agj2.20078.
Interpretive Summary: The fly commonly known as the sunflower seed maggot is a sunflower pest that also infests Silphium, a group of plants closely related to sunflowers that are being explored as potential new crops. Observations of flies emerging from Silphium heads in North Dakota showed that some Silphium species are more heavily infested by this pest than others. But even when many flies infested Silphium heads, seed production was not affected. Fly infestation in a second year was also very low. Combined observations in two locations over two years suggest the sunflower seed maggot is not likely to limit seed production in Silphium.
Technical Abstract: Neotephritis finalis (Loew), a fly known as a minor pest of cultivated sunflowers (Helianthus annuus L.), has also been observed to attack Silphium spp., which are being evaluated as new crops to produce biomass or edible oil. Fly infestations of Silphium integrifolium Michx., Silphium perfoliatum L. and their interspecific hybrid were assessed by securing bags over heads late in bloom and counting emerged adult flies ˜ 40 d later as a proxy for number of successful larvae. Effects on seed production were assessed by examining the percent of achenes containing fully developed seeds (i.e., seed set). In 2017, far more flies emerged from S. integrifolium and hybrids than from S. perfoliatum, but even high numbers of adult flies emerged per head appeared unrelated to seed set in S. integrifolium. In 2018, far fewer flies were found across all Silphium spp, but seed set was similar to 2017. Combined, results suggest that N. finalis is unlikely to limit seed production of Silphium spp.