Movement of apterous Sitobion avenae (Homoptera: Aphididae) in response to leaf disturbances caused by wind and rain

Abstract

The effect of wind and rain on initiation of dispersal and subsequent distances moved by apterous Sitobion auenae was quantified in five laboratory experiments. Wind duration and type (steady and gusting), rain duration and intensity, and a combination of wind and rain were investigated. With increased duration of wind there was an increase in the average distance aphids moved. There was less movement when aphids were exposed to gentle gusting, than to steady wind or strong gusting. With increased duration of rain there was an increase in the proportion of aphids lost from plants. Under heavy rain, the proportion of aphids off the release plant, the distance moved by them and the proportion of aphids lost, was greater than for drizzle or light rain. When wind and rain were compared, rain had the greater impact on aphid dispersal. It was concluded that leaf disturbances caused by strong gusts of wind or large rain droplets are of considerable importance in the initiation of aphid dispersal, but that wetness alone is not.

Comparative survival of insecticide-susceptible and resistant peach-potato aphids, Myzus persicae (Sulzer) (Hemiptera: Aphididae), in low temperature field trials

“…Wind and rain are known to dislodge aphids from plants (Le Roux, 1959;Tamaki, 1974;Gupta & Yadava, 1990;Mann et al, 1995) and cold and wet conditions restrict aphid movement (Harrington & Cheng, 1984). Aphids with greater resistance to insecticides may be dislodged more readily and winter weather may prevent their return.…”

Reduced wind strengthens top‐down control of an insect herbivore

“…Similarly, predators and prey often differ in size and mobility, which are traits that affect evaporation, convection, and other physiological processes (Church 1960, Denny 1993. Finally, wind destabilizes the physical environment, which can impede locomotion or crush organisms (Cannon 1986, Vogel 1994, Mann et al 1995. I report on an experimental investigation of the effects of wind on soybean aphids (Aphis glycines) and multicolored Asian ladybeetle (Harmonia axyridis).…”

Releases of a natural flightless strain of the ladybird beetle Adalia bipunctata reduce aphid-born honeydew beneath urban lime trees

“…Local insect communities in the trees could interact with the aphids and the ladybirds released. The heavy showers might have washed off the honeydew from the leaves, and washed off or disturbed the aphid populations (Mann et al 1995), resulting in lower honeydew levels in the following days. This may explain part of the observed decline in honeydew.…”