Jd. Burd et al., EFFECTS OF THE APHICIDES GAUCHO AND CGA-215944 ON FEEDING-BEHAVIOR AND TRITROPHIC INTERACTIONS OF RUSSIAN WHEAT APHIDS, The Southwestern entomologist, 21(2), 1996, pp. 145-152
The effect of low concentrations of the systemic aphicides CGA 215944
and Gaucho(R) (imidacloprid) on the feeding behavior of the Russian wh
eat aphid, Diuraphis noxia (Mordvilko), on wheat was evaluated using e
lectronic feeding monitors. Aphids began surviving 15 days after treat
ment with CGA 215944 (soil drench, 10 g AI/liter) and 45 days after pl
anting on plants grown from seed treated with Gaucho (1 fluid oz/cwt).
Following these periods of acute toxicity, CGA 215944 exhibited antif
eedant effects on D. noxia that were expressed by changes in the frequ
ency and duration of different feeding behaviors. Aphids on plants tre
ated with CGA 215944 spent significantly more time in nonprobing activ
ities and had a much higher frequency of leaf penetration, followed by
significantly shorter periods of phloem ingestion. Immediately after
the period of acute aphid toxicity, there were no substantial carryove
r effects from CGA 215944 or Gaucho on the tritrophic relationship bet
ween host plant, D. noxia, and Diaeretiella rapae McIntosh.