POST‐LANDING BEHAVIOR OF ALATE MYZUS PERSICAE AS ALTERED BY (E)‐β‐FARNESENE AND THREE CARBOXYLIC ACIDS

Abstract

The potential of 4 chemicals for disrupting the host-selection behavior of the aphid, Myzus persicae, was investigated using a flight chamber with both vertical and horizontal wind flow. (E)-13-farnesene (the aphid alarm pheromone) reduced probe durations, increased wandering, but did not reduce eventual settling. Undecanoic and dodecanoic acids (but not heptadecanoic acid) reduced all host-selection behaviors. Even after multiple landings, aphids never settled on surfaces treated with un-and dodecanoic acids. These laboratory data do not support the prospect that these chemicals would reduce non-persistent virus spread since aphids virtually always probed immediately after landing on any treatment. Other potential uses of these chemicals for aphid control are discussed.Ktv WORDS: Myzus persicae m Aphid alarm pheromone --(E)-l~-farnesene --Aphid repellents-Vertical flight tunnel.

Alarm Pheromones—Chemical Signaling in Response to Danger

“…In the sugar-cane woolly aphid, Ceratovacuna lanigera Zehntner (Homoptera, Pemphigidae), the alarm pheromone reportedly elicited aggressive behavior from conspecifics (Arakaki, 1989). Eßf has also a repellent effect on the landing behavior of alate aphids, which can cause them to choose an alternative host plant (Lambers and Schepers, 1978;Phelan and Miller, 1982;Wohlers, 1982). Field experiments confirmed dispersal behavior of aphids subjected to their alarm pheromone in 41 species (Xiangyu et al, 2002).…”

Alarm pheromones and allelochemics as a means of aphid control

“…Dodecanoic acid, which shortens the first probe (Phelan and Miller, 1982), was found to decrease acquisition of semi-or persistent viruses and to increase that of the nonpersistent PVY . In field trials, dodecanoic acid-treated field beans or beets were less colonized by Aphisfabae, but secondary spread of virus yellows in sugar beet was not reduced (Herrbach, 1985c(Herrbach, , 1987.…”

Wind Tunnels in Pheromone Research

“…The part of the tunnel with vertically moving air was Figure 8. Diagram of wind tunnel used by Phelan and Miller (1982) to generate both vertical and horizontal wind to study the responses of flying Myzus persicae aphids to their alarm pheromone and various fatty acids. Aphids fly toward light in the ceiling, but the operator counteracts their upward movement with downward-moving air generated by fan at upper right.…”

“…Also, air movement can be stopped in a horizontal tunnel to observe pheromone-mediated movements lacking an anemotactic component. Finally in at least one tunnel, horizontal air flow has been superimposed on vertical air flow to create an elaborate assay for a pheromone's behavioral effects (phelan and Miller, 1982).…”

“…An elaborate wind tunnel utilizing horizontal and vertical wind was used by Phelan and Miller (1982) to try to disrupt landing on host plants or host plant models by aphids by introducing clouds of the aphids' alarm pheromone over the plants (Fig. 8).…”