| frequency of resistance to bacillus thuringiensis toxin cry1ab in southern united states corn belt population of european corn borer (lepidoptera: crambidae). | the high-dose refuge resistance management strategy is the main approach used to delay resistance in targeted pests to bacillus thuringiensis (bt) toxins in transgenic crops. we used an f2 screen to test a critical assumption of the high-dose refuge strategy, which is that resistance allele (r) frequencies are initially rare (<10(-3)) in ostrinia nubilalis (hübner) (lepidoptera: crambidae) from the southern corn belt. we expanded the methodological scope of the f2 screen so that both males and f ... | 2006 | 16686153 |