The role of temperature, photoperiod, crowding and plant quality on the production of alate viviparous females of the bird cherry-oat aphid,Rhopalosiphum padi

Experiments indicated that for offspring of apterousRhopalosiphum padi (L.) (Hemiptera: Aphididae), photoperiod and crowding were the most important determinants of wing development whereas crowding and plant quality were more significant for the next generation. Plant quality became increasingly important as temperature increased while crowding became less so. More alates developed on plants previously infested with aphids, indicating that aphid feeding reduced plant quality. High temperature suppressed alatoid production, but could be overcome by crowding. Temperature appeared to influence wing development indirectly rather than directly by acting on the aphid through the plant. Adult weight and potential fecundity were also reduced for aphids which fed on previously infested plants.