Vine phylloxera: causes and control measures

2024 Author: Henry Conors | [email protected]. Last modified: 2024-02-12 02:47

Every gardener or owner of a summer cottage would like to grow fragrant, juicy grapes, which can be shown to experienced agronomists. However, in fact, this process is very troublesome, because during the season you often have to face many difficulties, including pests. And one of the most common diseases is aphids. If you find these insects on the bushes, you should not panic, because grape phylloxera is easily defeated if you recognize the enemy in time and start to act correctly, in a timely manner.

What does the leaf form of the disease look like

Detecting aphids is easy enough if you pay attention and look closely at the plants. Specific galls on the leaves, resembling warty formations of a spherical shape, indicate that the grapes have leaf phylloxera. If swellings are visible only on the lower side of the green mass, then this is the primary infection of the bush, and if on the upper side, then the larvae have already repopulated.

It is worth noting that the intensityThe development of phylloxera on plants can be different and directly depends on the immunity of the bushes and their age.

So, if phylloxera (growths on grape leaves) is clearly visible to the naked eye, the fight against it should begin immediately. However, experts also distinguish between the root form of the disease, due to which the bushes slow down their growth, the leaf becomes small, and fruiting is poor. Visually, the plant is simply oppressed, and in order to establish the exact cause of its disease, it will be necessary to take samples for detailed study more than once.

How to recognize the root form of the disease

In order to detect the presence of aphids or traces of their stay on the root system, you need to dig out a few suspicious vines or surface roots. Experts recommend doing the procedure in the second half of summer, since it is during this period that the pest actively multiplies and is easier to detect. Soil must also be present on the sample taken. Carefully separate the lumps of earth with a sharp thin knife or scalpel and examine the contents of the cracks in the bark. If grape phylloxera is present on them, then the grower will notice small swellings on small roots, and on thick ones - clusters of aphids that resemble yellow spots. They will be roundish, no more than 1 centimeter in diameter. It is noteworthy that the affected root tips take on a hooked or club-shaped shape with yellowish-white nodules, which darken over time, disintegrate, and then become almost indistinguishable. The bark resembles a sponge, crumbles, and the root itself looks dried up.

At the very beginning of the disease, phylloxera on grapes is almost invisible and can only be detected in the fifth year, so the procedure for control digging will have to be done annually. It is important to remember that insects most often live in areas bordering on the focus of infection, since they always leave completely diseased plants and multiply on he althy ones. The pest is able to colonize both on the surface of the root and on the part located at a depth of just over a meter. For inspection, you need to choose samples taken from living bushes.

The birthplace of phylloxera, when and where was it discovered

The homeland of the most dangerous quarantine pest is the southeastern part of the United States. Most often it was found on wild shrubs growing in the Mississippi River basin. The first defeat of vineyards was recorded in 1868 in Europe. It is known from history that in the 19th century grape phylloxera destroyed more than 6 hectares of plantations, and appeared in Russia in 1880. The great winegrower V. E. Tairov noted that aphids are the most terrible and stubborn pest, since they live on roots and foliage, destroy bush after bush, and bring only devastation and disaster everywhere. In the second half of the century, the pest appeared in the south of France and spread with extraordinary speed to almost all European regions.

It is worth noting that in a short period of time phylloxera destroyed over 70% of vineyards around the globe.

Root Pest Lifestyle

Grape aphid has an extremely complex life cycle and is divided into the following forms:

• underground;
• ground;
• providing communications (winged).

So, absolutely all aphids that infect the root system are exclusively female. Insects are distinguished by the absence of wings, yellow-green coloration with small dark dots on the back. Their sucking proboscis extends from the head to the ventral part of the body and is able to pierce the roots of the bush to suck out food. Within 4-6 weeks, females lay hundreds of yellowish eggs, of which, after 8-10 days, larvae with a particularly long proboscis are born. The pest of this form prefers to settle on old plants and winter on them.

It is noteworthy that the larvae that survived until spring are very resistant to cold, and the fight against them will not be easy.

Winged Shape Lifestyle

In late summer - early autumn, among the root aphids, you can see nymphs - thinner orange individuals with rudiments of wings. They develop more actively in conditions of high humidity and certain weather conditions. Insects crawl to the surface and after the 4th molt finally turn into a winged form with long tentacles, as well as well-developed eyes. Such a pest is already able to fly short distances, lay on the buds of grapes, the underside of the leaf and loose bark.unfertilized eggs. Smaller larvae grow into males that live only up to 10 days, because they cannot eat due to the lack of proboscis. However, after a single sexual intercourse, the female lays one fertilized egg, which will winter in the cracks and crevices of old wood.

Leaf Shape Lifestyle

With the onset of spring, a female wingless aphid hatches from a winter egg, initially settling on 1-6 leaves. Gradually, it moves higher and higher, sucking all the juices from the top of the green mass. In places of punctures, a green gall is formed with a concave shape, sometimes with reddish spots. In just a few weeks, grape phylloxera lays more than 1000 eggs, of which, after 8 days, young individuals appear, settling on fragile shoots. The pest will quickly crawl up, and when the plant is already completely infected, it moves to other bushes. It is noteworthy that under favorable conditions, up to 5 generations of aphids can develop in one season. By autumn, the pest becomes even larger, its body is much stronger, and its proboscis is longer. Despite the fact that the leaf form dies along with fallen leaves, such a phylloxera on grapes endures control measures very steadfastly.

How phylloxera spreads

Grape aphid root, leaf and winged forms are able to move very actively along green shoots, foliage and in the soil. Sometimes underground individuals find themselves on the surface, where they move for hours without food and rest at a speed of 3 cm per minute. Winged insects overcome up to 100meters. Also, grape phylloxera passively moves long distances with wind currents, mud or rainwater. There are cases when the pest overcame about 30 kilometers. The person himself, who acquires infected grafting and planting material, processes he althy plants with dirty tools, also contributes to the spread of the disease.

In addition, the pest is carried by wild animals and birds.

What is the danger of phylloxera

In the course of its life, phylloxera, first of all, affects the root system, so the bush receives less nutrients every year or stops absorbing them altogether. Growths, nodules and nodules completely isolate the underground parts of the plant, as a result of which they die from starvation. Young bushes can begin to dry out 3-5 years after the defeat, and older ones much later. The shoots of weakened grapes do not have time to ripen, so they often do not tolerate winter frosts.

If we consider the focus of the lesion, we can see that its outlines are oval in shape, because the pest spreads in all directions from the object of primary infection. How to treat grape phylloxera, and a photo with a detailed description of the pest is easy to find in many sources, but it is best to purchase disease-resistant varieties.

Which varieties of grapes are best planted on the site

Since the pest mainly settles on American grape varieties, experts recommend growing Europeanplant species by planting them in the sands. It is also rational to switch to complex-resistant new varieties or Save-Villar hybrids. It is also safe to use European grape varieties resistant to phylloxera at the time of grafting.

Recommended rootstock varieties:

• Kober 5BB;
• Riparia x Rupestris 101-14;
• Riparia Gluar.

The roots of these plant species are resistant to the process of decay and do not die at the time of infection with phylloxera.

Folk methods of dealing with phylloxera

After grape phylloxera has been identified, the fight against it should begin immediately. If the spread of the pest is insignificant, then improvised means can be completely dispensed with. So, they try to wash off harmful insects with a large pressure of water, after which they become prey for birds. The procedure should be done several times.

Also, many advise preparing various types of solutions:

• Soapy (100 g of tar soap dissolved in 10 liters of water). It is possible to mix soap with a small amount of washing powder and detergent, but it is better to avoid products that are too fragrant, as they attract insects.
• From the ashes (1 cup per 5 liters of water and infuse for 12 hours).
• From the peel of citrus fruits (boil 0.5 liters of powdered substance in 1 liter of water, filter and add another 10 liters of liquid).
• From the tops of nightshade plants (half fill a 3-liter bottle with finely chopped greens and pourboiling water up to the neck. Insist for a day, then add 1 tbsp. l. soap shavings or powder).
• Tobacco (1 glass of tobacco leaves brew in 5 liters of water, insist and strain).

In addition, many experienced growers advise attracting beneficial insects, birds to the plantations and planting fragrant herbs or flowers next to the bushes.

Chemicals to combat phylloxera

Of course, not all summer residents believe in folk methods of dealing with aphids, so they prefer to purchase ready-made products in specialized stores. It is advisable to treat grape phylloxera with insecticides, which are practically not washed off by precipitation and are absolutely safe for honey bees.

The most common aphid medications:

• "Fastak" (combined with other fungicidal and insecticidal agents);
• "Phozalon" (destroys aphids and protects plants for a long period, exhibits toxic activity even at low temperatures);
• "Actellik" (prevents re-settlement);
• "Kinmiks" (kills adult phylloxera and all types of larvae);
• "Confidor" and "Bi-58" (destroy the leaf form of the pest).

It is also important to completely destroy the foci of infection by applying a flammable, volatile carbon disulfide that penetrates deep into the soil. Quarantine measures are recommended to protect other plants from aphids.