HOSTPLANT SPECIFIC COLOUR BEHAVIOUR BY HYALOPTERUS-PRUNI (APHIDIDAE)

Emigrants of Hyalopterus pruni (flying outdoors) are attracted to colour plates in the range of orange-yellow-green with an optimum at yellow, but only when these colours are unsaturated tints - i.e. when they are mixed up with white lead. (Maximum alighting occurred at a reflection of about 35%, in the range of 320-460 nm). Leaf areas of Phragmites communis Tr. (9.5×9.5 cm) attracted twice as many landings as beet leaves (Beta vulgaris L.) From this it is concluded that a limited degree of alighting on a specific hostplant is caused by specific adaptation to the unsaturated colour of the hostplant, Phragmites. In contrast to H. pruni, Aphis fabae prefers the more saturated colours and Beta-leaf to those of Phragmites. © 1969 North Holland Publishing Company.