Impact of Triclopyr Amine onGalerucella calmariensisL. (Coleoptera: Chrysomelidae) and a Step toward Integrated Management of Purple LoosestrifeLythrum salicariaL

• Published in: Biological control Vol. 12; no. 1; pp. 14 - 19
• Main Authors: Lindgren, Cory John, Gabor, T.Shane, Murkin, Henry R.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.05.1998
• Subjects: classical biological control; Garlon 3A; herbicide intervention; integrated vegetation management; leaf-eating beetle; purple loosestrife; herbicide intervention; purple loosestrife; integrated vegetation management; classical biological control; leaf-eating beetle; Garlon 3A
• ISSN: 1049-9644; 1090-2112
• DOI: 10.1006/bcon.1997.0607

There is a need to investigate the potential for the integration of classical biological control strategies with herbicidal control strategies for the management of purple loosestrife (Lythrum salicaria) in North America. The objectives of this study were to determine the effects of triclopyr amine at 12 kg/ha on the survival and fecundity of adultGalerucella calmariensisand on the ability of third instar larvae to pupate through to teneral adults. To examine the effects of triclopyr amine on oviposition, adultG. calmariensiswere divided into three experimental groups: a direct contact group, an indirect contact group, and a control group. Each experimental treatment was replicated three times. Twenty adults (10 pairs) were used in each replication. Differences were not detected between the number of adults that survived in each of the three groups, the total number of eggs oviposited by adults in each group, or the total number of egg masses oviposited in each group. However, the adults in the indirect contact group oviposited significantly smaller mean egg-batch sizes. Eggs oviposited by each group were placed in petri dishes and monitored until the third instar stage when they were transferred to pupation chambers. Differences were not detected between the mean number of new generation adults produced between experimental groups. To examine the effect of triclopyr amine on the ability ofG. calmariensisthird instar larvae to pupate to teneral adults, third instar larvae were divided between a control group and a triclopyr amine group. Larvae were sprayed to wetness with triclopyr amine at the rate of 12 kg/ha, placed into pupation chambers, and monitored for adult emergence. Differences were not detected between the number of larvae that pupated through to teneral adults in the control group vs the triclopyr amine group. Based upon these results we conclude that triclopyr amine is compatible with the classical biological control agentG. calmariensis.