Weed Science (1999) 47, 360-365
Elizabeth J. Stamm Katovich, Roger L. Becker and David W. Ragsdale (1999)
Effect of Galerucella spp. on survival of purple loosestrife (Lythrum salicaria) roots and crowns
Weed Science 47 (3), 360-365
Abstract: Starch levels, used as a measure of plant stress, were not consistently reduced in root or crown tissue of purple loosestrife plants after 2 yr of severe Galerucella calmariensis or Galerucella pusilla (Coleoptera: Chrysomelidae) defoliation. Early in the season, defoliation from Galerucella spp. approached 100%, but the majority of Lythrum salicaria plants regrew by the end of August, resulting in an average reduction of 81% of the aboveground biomass compared to the control. The stress imposed by Galerucella spp. defoliation was less than that achieved from more severe stress imposed by mechanical shoot clipping at 2- or 4-wk intervals from June to October. Both shoot-clipping treatments killed the majority of plants after one growing season. Galerucella spp. feeding reduced plant stature, which may reduce competitiveness. However, considering the extensive carbohydrate reserves present in the large woody crowns of Lythrum salicaria, it will require in excess of 2 yr of consistent, severe leaf defoliation to cause plant mortality. A combination of stresses, such as winter crown injury, or other biological control agents in addition to Galerucella leaf defoliation may be required for plant mortality.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Elizabeth J. Stamm Katovich, David W. Ragsdale
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution
Pest and/or beneficial records:
| Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
|---|---|---|---|---|
| Lythrum salicaria (weed) | ||||
| Neogalerucella calmariensis (weed bioagent) | Lythrum salicaria (weed) | |||
| Galerucella pusilla (weed bioagent) | Lythrum salicaria (weed) |
