Transgenic strawberry lines constitutively expressing the cowpea trypsin inhibitor gene (CpTi) were examined under field conditions to determine if this gene offered protection against the feeding of vine weevil (Otiorhynchus sulcatus). Data are presented on plant performance over three seasons (years) [date not given]. Field results for two years confirmed previous glasshouse findings and demonstrate protection in terms of attack by vine weevil larvae on all the transgenic lines. Over three years, two 'Melody' lines and three 'Symphony' lines continued to demonstrate significantly improved plant growth compared with the control lines. The genotype into which CpTi was inserted had a significant effect on performance. The CpTi has a significant effect on vine weevil in terms of a reduction in the number of pupae. The numbers of Carabid and other non-target arthropods were assessed over the duration of the trial, and were significantly affected by the CpTi transgenic lines.