Conditioning host plant affects antixenosis and antibiosis to Russian wheat aphid (Homoptera: Aphididae). uri icon

abstract

  • The effects of conditioning host on antixenosis and antibiosis of test hosts to Diuraphis noxia (Mordvilko) were studied. Three methods of measuring antixenosis were compared and found to be approximately equally effective. Apterous D. noxia reared on a resistant barley, Hordeum vulgare L., showed no preference between four barleys; but oats, Avena sativa L., were less preferred. D. noxia reared on wheat, Triticum aestivum L., generally showed no preference between four barleys and wheat. There was no difference between two clones of D. noxia in the antixenosis and antibiosis of two barleys (one resistant and the other susceptible to D. noxia), wheat, and oats. Conditioning host influenced antixenosis as evidenced by a significant interaction between the effects of conditioning host and test host. D. noxia conditioned on the barleys and wheat showed no preference for these genotypes, but oats were less preferred. D. noxia conditioned on oats showed an increased preference for oats relative to the two barleys and wheat compared with aphids conditioned on the two barleys and wheat. Conditioning host influenced antibiosis as evidenced by a significant interaction between the effects of conditioning host and test host. D. noxia conditioned on one of the barleys contained more embryos than expected when tested on oats. However, D. noxia transferred from any of the conditioning host plants to oats contained significantly fewer embryos than they did on other test hosts on which the number of embryos was similar.

publication date

  • 1993
  • 1993