In 2009, a novel solution to the resistance problem was trialed in Arizona, when sterile male pink bollworms (Pectinophora gossypiella) were released into populations of their wild Bt-resistant counterparts. The hypothesis was that sterile males mating with the few surviving females, who had developed resistance, would lead to a decrease in pests in the following generation. There was a dramatic reduction in pink bollworms, with only two pink bollworm larvae being found by the third year of the study.[1]