family: phylloxeridae
species: daktulosphaira vitifoliae
common names: grape phylloxera
hosts: grapes
cultural control methods: resistant rootstocks. hot water treatment may eliminate infestations
pesticides used: there are no chemical control treatments (systemics ?)
notes: An aphid like insect. Adult female remains localized on grape roots and deposits eggs around her. Upon hatching, nymphs settle close to their mother or move through cracks and crevices in the soil to new roots of the same or different vine. There are 5-8 generation per year.

Agriculture and Agri-Food Canada Insect Identification Sheet No. 89 1983

Grape Phylloxera

Phylloxera vitifoliae (Fitch)

The grape phylloxera is a serious pest of grapevines in Canada. It attacks leaves of susceptible varieties causing grotesque galls. Coincidental with the development of the wine grape industry, it has become an important pest wherever grapes are grown.

Damage:

Grape phylloxera causes the plant to form galls on the underside of leaves and occasionally on shoots and tendrils of more susceptible varieties. Leaf galls may be the size of a small pea; inside there may be one or more adult females and hundreds of eggs and hatching young. Leaf galls can become numerous. On very susceptible varieties, there may be as many as 200 galls per leaf with 50-80% of the leaves being infested. Heavily infested leaves die prematurely and fall from the vine. Defoliation can retard fruit ripening and reduce normal shoot growth. The wild grapevines appear much more susceptible than commercial wine varieties.

Life History:

The insect overwinters in the egg stage. In early spring a female hatches and migrates to a developing leaf to feed. This causes an irritation in the plant tissues and a gall is formed. When mature, the female produces numerous parthenogenetic young that migrate to form new galls. After a few generations, some fall to the ground and burrow into the roots to feed. In midsummer, winged adults emerge from the ground to lay eggs on the vines. These develop into true males and females. After mating, the females lay a single egg on the vine, completing the life cycle.

Flight activity varies but usually occurs in late July or early August and ends by mid-September. A knowledge of the seasonal activity is valuable to protect new wine grape plantings.

Control:

Grape phylloxera has several natural enemies. These predators, which act as biological control agents, include green lacewings, thrips, mites, minute pirate bugs and a predatory fly. For heavy infestations consult your provincial Department of Agriculture for recommendations.

Grape phylloxera

Daktuloshpaera vitofoliae

Phylloxeridae

Fairly complicated life cycle: the females reproduce asexually on grape roots first instars are called crawlers not mobile thereafter all develop into reproducing adults three or four generations per year temperature quite variable as they can descend as deep as the roots go. The alates are winged morphs that may be able to reproduce sexually to produce overwintering eggs. These emerge in the spring to feed on grape leaves. The insects feed by inserting proboscis and injecting saliva to induce plant to produce gall nodocities. The leaf galls are different in gall production in that theirs encases the animal. It's basically a sack that encloses the insect. In DA in vineyard they only have root form in the desert they may have leaf form. The animal is controlled by using resistant root stock.

Grape phylloxera (Daktulosphaera vitifoliae) is an economically important homopteran pest of grape vines. Native to North America but now established throughout the world the insects feed by inserting their proboscises into the roots of grape vines and extracting plant nutrients from there. Gall "tuberosities" are induced at these feeding sites which serve as nutrient sinks. These are essential to the establishment and survival of the phylloxera — inability to induce such growths results in the death of the pest. The pest is controlled by use of resistant rootstock.