ABSTRACT

Dow AgroSciences, LLC has genetically modified cotton (Gossypium hirsutum L.) to express two separate insecticidal crystal proteins from the bacterium Bacillus thuringiensis (Bt) for the control of key lepidopteran pests. Cotton genotype GC510 was transformed to contain the genes that express full-length synthetic protoxins (synpro) of Cry1F or Cry1Ac. Transgenic lines were backcrossed with a non-transgenic elite variety, PSC-355. Subsequently, Cry1F(synpro) and Cry1Ac(synpro) lines were crossed to produce the stacked product, MXB-13. Dow AgroSciences transgenic cotton event MXB-13 provided excellent control of the secondary foliar feeding lepidopterous insects such as beet armyworm (Spodoptera exigua), cabbage looper (Trichoplusia ni), soybean looper (Pseudoplusia includens), southern armyworm (Spodoptera eridania) and fall armyworm (Spodoptera frugiperda). Significantly lighter foliar damages or fewer foliage-feeding larvae were detected on unsprayed MXB-13 plots, as compared to those on the unsprayed non-Bt cotton variety.