Green peach aphid

Description

Wingless adults are 1.5 to 2 mm (0.058-0.078 inch) long; their color varies from yellow, through all shades of green, to pink, red or black.

Damage

In the spring, the aphids first propagate on peach. If they are numerous, curling of leaves and distortion of shoots can occasionally be observed. 
Myzus persicae sometimes causes direct feeding damage on some other crops as well, partly because of its toxic saliva. Symptoms can include dwarfing, wilting or curling of leaves. High population densities can lead to water stress, reduced growth and eventually, to decreased yield. However, most of the symptoms - typically yellowing of leaves and chlorotic spots - and most of the damage are caused by the numerous viruses this aphid species transmits.

Lifecycle

Myzus persicae comprises a number of host races, which are sometimes described as separate species; the systematic status of M. nicotianae is particularly doubtful. 
The winter host is nearly always Prunus spp., especially P. persica (peach), but often the aphid is anholocyclic, wherever the climate allows the overwintering of active stages. 
In spring, after several generations have occurred, the increasing population density causes winged morphs to appear, which leave the tree and disperse onto the potential summer hosts. The aphid often stops to deposit some nymphs, then flies again, visiting and possibly infesting a number of plants in this way. 
In autumn, the aphids migrate back to P. persica, where mating occurs and the eggs are deposited. Aphids that have returned to peach in the autumn tend to be found on senescent leaves, mostly along the veins, whereas on summer hosts, the youngest tissue carries the largest aphid population.