Transformation of eggplant with synthetic cryIIIA gene produces a high level of resistance to the Colorado potato beetle.

摘要

A population of 300 putative transgenic aubergines (Solanum melongena) carrying the syn cryIIIA gene from Bacillus thuringiensis was produced and tested for resistance to the Colorado potato beetle (CPB, Leptinotarsa decemlineata). Toxicity tests inplanta and in vitro showed that 69% of the transformed plants were resistant to neonate larvae and adult CPB. Transgenicity of the plants was confirmed by investigating beta-glucuronidase (GUS) expression, and by Southern and northern analyses. Upon selfing, primary transformants (with a single insert of the construct) generally produced progenies cosegregating for the uidA and syn cryIIIA genes at the expected 3:1 ratios. In a few exceptions, only one of the genes was expressed. The latter was attributed to the gene silencing phenomenon. The segregating resistant R1 seedlings showed the same level of resistance as the parental genotypes in growth chamber tests and under field conditions. Upon selfing, a genotype carrying 2 copies of the construct segregated at a 15:1 ratio for GUS expression and resistance to CPB, and Southern analysis revealed a 9:3:3:1 genotypic segregation ratio for individual copies of the construct.