When the plants ofthe four Bt genotypes, Tv16, TH9,
LE124 and LE186, were artificially infested with H.
armigera larvae in the field, leafand fruit damage on
these Bt genotypes was significantly lower than the nontransgenic
control (Fig. 1). In 1999, when the six Bt
tomato hybrids were infested with H. armigera larvae,
leafan d fruit damage on the plants was lower than on
the non-transgenic hybrids. Ofthe six Bt hybrids, the
hybrids Tv16TH9 and LE124LE186 suffered the
lowest damage by H. armigera (Fig. 2). These results
indicate that cry1Ab gene expression within the tomato
genotypes, Tv16, TH9 and LE124, was sufficient to kill
H. armigera larvae under field conditions. Gene expression
was equally high in the tomato hybrids