Oviposition preference and offspring performance of Eurosta solidaginis ongenotypes of Solidago altissima

We studied the relationship between oviposition preference and offspring pe rformance in Eurosta solidaginis, fly that induces galls on tall goldenrod, Solidago altissima. In a garden experiment, we measured the oviposition pr eference and performance of E. solidaginis on four replicates of 20 genotyp es of Solidago altissima for two years. No evidence was found of an oviposi tion preference based on plant genotype. E. solidaginis survival was influe nced by plant genotype in 1991, but not in 1990. In 1991 there was no corre lation between the preference for plant genotypes and larval performance on these genotypes. More rapidly growing ramets were ovipunctured more freque ntly. However, survival was highest on ramets with intermediate growth rate s. On a per-plot basis, there was no relationship between mean growth rate and oviposition preference or offspring performance. In both 1990 and 1991 there was no significant correlation between preference and performance amo ng plots. There were no significant positive correlations between years in the experimental garden in E. solidaginis preference for, or performance on , S. altissima genotypes. There were also no significant positive correlati ons between preference and performance by E. solidaginis for S. altissima g enotypes in the field and in the experimental garden. This indicates a high degree of plasticity in plant traits related to oviposition preference and offspring performance.