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Seasonal Abundance Of Ground Beetles In Highbush Blueberry (Vaccinium Corymbosum) Fields And Response To A Reduced-Risk Insecticide Program, Matthew E. O'Neal, K. S. Mason, R. Isaacs Apr 2005

Seasonal Abundance Of Ground Beetles In Highbush Blueberry (Vaccinium Corymbosum) Fields And Response To A Reduced-Risk Insecticide Program, Matthew E. O'Neal, K. S. Mason, R. Isaacs

Matthew E. O'Neal

Seasonal patterns of ground beetle activity were examined at six highbush blueberry (Vaccinium corymbosum L.) farms in southwestern Michigan. On each farm, pitfall traps were used to monitor ground beetle activity in two adjacent fields: one managed under a conventional insecticide program (grower standard) and the other with reduced-risk insecticides. Overall, more active ingredient was applied in grower standard than reduced-risk fields, with the greatest amount used in June and July. During the 6-mo sampling period, we collected 11,322 ground beetles comprised of 34 species, with Harpalus pensylvanicus DeGeer representing 70.7% of the total beetles collected. The greatest amount of …


Corn Phenology Influences Diabrotica Virgifera Virgifera Emigration And Visitation To Soybean In, Matthew E. O'Neal, D. A. Landis, J. R. Miller Feb 2004

Corn Phenology Influences Diabrotica Virgifera Virgifera Emigration And Visitation To Soybean In, Matthew E. O'Neal, D. A. Landis, J. R. Miller

Matthew E. O'Neal

We used two types of laboratory apparatus to test whether rotation-resistant and wild-type Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) responded differently to corn phenology. Beetles from Nebraska where injury to rotated corn has not been reported were defined as wild type, and beetles from Illinois where injury to rotated corn is common represented “rotation-resistant“ populations. A two-chamber emigration arena assayed propensity of both populations to leave corn during and after anthesis. A side-arm olfactometer tested whether the relative attraction of beetles to soybean versus corn was influenced by corn phenology. Beetle origin did not influence departure from corn of varying …


Does Landscape Diversity Slow The Spread Of Rotation-Resistant Western Corn Rootworm (Coleoptera: Chrysomelidae)?, D. W. Onstad, D. W. Crwoder, S. A. Isard, E. Levine, J. L. Spencer, Matthew E. O'Neal, S. T. Ratcliffe, M. E. Gray, L. W. Bledsoe, C. D. Di Fonzo, J. B. Eisley, C. R. Edwards Oct 2003

Does Landscape Diversity Slow The Spread Of Rotation-Resistant Western Corn Rootworm (Coleoptera: Chrysomelidae)?, D. W. Onstad, D. W. Crwoder, S. A. Isard, E. Levine, J. L. Spencer, Matthew E. O'Neal, S. T. Ratcliffe, M. E. Gray, L. W. Bledsoe, C. D. Di Fonzo, J. B. Eisley, C. R. Edwards

Matthew E. O'Neal

A behavioral change in some western corn rootworm (Diabrotica virgifera virgifera LeConte) populations is threatening the effectiveness of crop rotation, a successful management strategy for controlling this pest. We created a set of simple meteorologic and behavioral models that can be used to predict the spread of the beetle infesting soybean (Glycine max (L.)) throughout the midwestern United States. We used data collected in Illinois, IN, MI, and Ohio to create maps of observations to evaluate the model. We displayed data on the maps using detection thresholds for western corn rootworm in soybean fields of 10 or 20 beetles per …


An Inexpensive, Accurate Method For Measuring Leaf Area And Defoliation Through Digital Image Analysis, Matthew E. O'Neal, Douglas A. Landis, Rufus Isaacs Dec 2002

An Inexpensive, Accurate Method For Measuring Leaf Area And Defoliation Through Digital Image Analysis, Matthew E. O'Neal, Douglas A. Landis, Rufus Isaacs

Matthew E. O'Neal

We report a protocol using a common desk-top scanner and public domain software for measuring existing leaf area and leaf area removed as a result of herbivory. We compared the accuracy and precision of this method to that of a standard leaf area meter. Both methods were used to measure metal disks of a known area, the area of soybean (Glycine max L.) leaves, and the area removed by simulating leaf feeding with a hole-punch. We varied the amount of injury across a low, medium, and high degree of simulated feeding. The mean area of 10 cm2 and 50 cm2 …