IMPACT OF TRICLOPYR AMINE ON GALERUCELLA-CALMARIENSIS L. (COLEOPTERA,CHRYSOMELIDAE) AND A STEP TOWARD INTEGRATED MANAGEMENT OF PURPLE LOOSESTRIFE LYTHRUM-SALICARIA L

There is a need to investigate the potential for the integration of cl assical biological control strategies with herbicidal control strategi es for the management of purple loosestrife (Lythrum salicaria) in Nor th America. The objectives of this study were to determine the effects of triclopyr amine at 12 kg/ha on the survival and fecundity of adult Galerucella calmariensis and on the ability of third instar larvae to pupate through to teneral adults. To examine the effects of triclopyr amine on oviposition, adult G. calmariensis were divided into three e xperimental 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. Differ ences were not detected between the number of adults that survived in each of the three groups, the total number of eggs oviposited by adult s in each group, or the total number of egg masses oviposited in each group. However, the adults in the indirect contact group oviposited si gnificantly smaller mean egg-batch sizes. Eggs oviposited by each grou p were placed in petri dishes and monitored until the third instar sta ge when they were transferred to pupation chambers. Differences were n ot detected between the mean number of new generation adults produced between experimental groups. To examine the effect of triclopyr amine on the ability of G. calmariensis third instar larvae to pupate to ten eral adults, third instar larvae were divided between a control group and a triclopyr amine group. Larvae were sprayed to wetness with tricl opyr 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 con trol group vs the triclopyr amine group. Based upon these results we c onclude that triclopyr amine is compatible with the classical biologic al control agent G. calmariensis. (C) 1998 Academic Press.