In these experiments we compared the performance ofA. lucorum
on two transgenic cotton cultivars, GK12 and SGK321, designed to
control lepidopteran pests such asH. armigera, as well as on two nontransgenic isolines Simian3 and Shiyuan321. Simian3 was the nontransgenic parental cultivar used to produce the GK12 cultivar that
expressed the Cry1Ac toxic protein. Similarly, Shiyua321 was the nontransgenic cultivar used to obtain SGK321, a cultivar expressing
Cry1Ac þ CpTI (Cowpea trypsin inhibitor gene) (Guo, 1995). These
cultivars were provided by colleagues at the Biotechnology Research
Institute of the Chinese Academy of Agricultural Science