The apterae of Myzus persicae are generally yellowish-green (see first picture below) but vary from whitish or pale yellowish green to mid-green, rose-pink or red (see second picture below). They are often darker in cold conditions. The antennae are 0.7-1.0 times the body length, reaching to the siphunculi. The antennal terminal process is usually longer than antennal segment III, 0.90-1.49 times its length (cf. Myzus certus and Myzus dianthicola, both of which usually have the terminal process shorter than antennal segment III). Their siphunculi are slightly swollen towards the darkened tips (cf. Myzus ornatus and Myzus lythri, which both have tapering siphunculi). The siphunculi are 1.9-2.5 times the length of the rather pointed cauda, and at least 0.82 times longer than antennal segment III (cf. Myzus ascalonicus and Myzus cymbalariae, which both have siphunculi less than 0.81 times longer than antennal segment III). The body length of Myzus persicae apterae is 1.2-2.3 mm.
The alateMyzus persicae (see first picture below) has a solid pigmented area occupying the mid-abdominal dorsum from segments 3 to 6, as well as further bars on adjoining segments. Immatures have no visible cauda and shorter siphunculi but otherwise resemble the adult apterae. The colony structure of Myzus persicae on secondary hosts is usually dispersed (see second picture below) (cf. Myzus antirrhinii, which forms large dense colonies).
The micrographs below show an aptera (note the slightly swollen, dark-tipped siphunculi) and an alate, both preserved in isopropyl alcohol.
Micrographs of clarified mounts by permission of Roger Blackman, copyright AWP all rights reserved.
The peach-potato aphid does host alternate where its primary host - peach (Prunus persica) occurs. Eggs are laid on the primary host and spring colonies curl the young leaves of peach. However, most of the population overwinters as mobile stages on secondary hosts: herbaceous plants and brassicas. Myzus persicae is a major pest of its summer hosts, including potatoes, sugar beet, lettuce, brassicas and legumes, mainly because it transmits a number of important plant viruses. Whilst Myzus persicae is a polyphagous generalist.
The subspecies Myzus persicae nicotianae is a tobacco specialist, but also occurs on a variety of other secondary hosts. In most of its range it is anholocyclic, but its primary host is Prunus persica.
Other aphids on same host:
Myzus persicae has been recorded on 33 species of the Prunus genus.
Myzus persicae has been recorded on 8 species of the Brassica genus (Brassica juncea, Brassica napus, Brassica nigra, Brassica oleracea, Brassica rapa, Brassica madritensis, Brassica racemosus, Brassica rigidus).