| limited genetic variation within and between russian wheat aphid (hemiptera: aphididae) biotypes in the united states. | insect biotypes are populations able to kill or injure crops with resistance genes and complicate pest management programs based on host plant resistance. biotypes occur in russian wheat aphid, diuraphis noxia (kurdjumov) (hemiptera: aphididae), a worldwide pest of wheat, triticum aestivum l., and barley, hordeum vulgare l., that was introduced into mexico in 1980 and then spread into texas by 1986. five d. noxia biotypes were described in the united states and given the number designations 1 th ... | 2009 | 19253666 |