Photo: Kochia, southwest Montana. © 2020 Delena Norris-Tull
DNA studies to identify biocontrol insects
Summary by Dr. Delena Norris-Tull, Professor Emerita of Science Education, University of Montana Western, July 2020.
Dr. Scott Nissen, at Colorado State University, told me: “In the 1990s, we got the idea that the folks working with biological controls were more interested in the insects and not the plants.
“I was in Nebraska at the time. We wanted to use molecular genetics to understand the genetics of the plant species leafy spurge. The biocontrol guys were going to Italy to get insects to use in controlling leafy spurge in the US. We did research using RFLP [a DNA research technique] to decide whether the spurge in Nebraska was related to the spurge from Pisa, Italy. We found that it was not even closely related, using very simple genetic markers. So the insects the biocontrol guys were bringing back from Italy weren’t compatible with the leafy spurge that had become invasive in Nebraska. Our invasive spurge came from the Ukraine. The root boring weevil, from the Ukraine, turned out to be a better biocontrol.
“Leafy spurge came to the US as early as the 1700s, from soil ballast in ships. The population of spurge along the US east coast did not spread.
“In Colorado, there is an insectary on the west slope, to raise biocontrol insects, for release on land owners’ properties to control leafy spurge.
“In 1993, I traveled throughout Europe examining the DNA of insects to locate insects that might be useful for biocontrol. It took a lot of effort to convince the USDA guys of the importance of that research.”
More challenges of using Biocontrol Agents:
DNA studies to identify biocontrol insects
Summary by Dr. Delena Norris-Tull, Professor Emerita of Science Education, University of Montana Western, July 2020.
Dr. Scott Nissen, at Colorado State University, told me: “In the 1990s, we got the idea that the folks working with biological controls were more interested in the insects and not the plants.
“I was in Nebraska at the time. We wanted to use molecular genetics to understand the genetics of the plant species leafy spurge. The biocontrol guys were going to Italy to get insects to use in controlling leafy spurge in the US. We did research using RFLP [a DNA research technique] to decide whether the spurge in Nebraska was related to the spurge from Pisa, Italy. We found that it was not even closely related, using very simple genetic markers. So the insects the biocontrol guys were bringing back from Italy weren’t compatible with the leafy spurge that had become invasive in Nebraska. Our invasive spurge came from the Ukraine. The root boring weevil, from the Ukraine, turned out to be a better biocontrol.
“Leafy spurge came to the US as early as the 1700s, from soil ballast in ships. The population of spurge along the US east coast did not spread.
“In Colorado, there is an insectary on the west slope, to raise biocontrol insects, for release on land owners’ properties to control leafy spurge.
“In 1993, I traveled throughout Europe examining the DNA of insects to locate insects that might be useful for biocontrol. It took a lot of effort to convince the USDA guys of the importance of that research.”
More challenges of using Biocontrol Agents:
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