Expression of the insecticidal lectin from snowdrop (Galanthus nivalis agglutinin; GNA) in transgenic wheat plants: effects on predation by the grainaphid Sitobion avenae

Transgenic wheat plants containing the gene encoding snowdrop lectin (Galan thus nivalis agglutinin; GNA) under the control of constitutive and phloem- specific promoters were generated through the particle bombardment method. Thirty-two independently derived plants were subjected to molecular and bio chemical analyses. Transgene integration varied from one to twelve estimate d copies per haploid genome, and levels of GNA expression from 0 to ca. 0.2 % of total soluble protein were observed in different transgenic plants. Se ven transgenic plants were selected for further study. Progeny plants from these parental transformants were selected for transgene expression, and te sted for enhanced resistance to the grain aphid (Sitobion avenae) by exposi ng the plants to nymphal insects under glasshouse conditions, Bioassay resu lts show that transgenic wheat plants from lines expressing GNA at levels g reater than ca. 0.04% of total soluble protein decrease the fecundity, but not the survival, of grain aphids. We propose that transgenic approaches us ing insecticidal genes such as gna in combination with integrated pest mana gement present promising opportunities for the control of damaging wheat pe sts.