Every gardener or owner of a summer cottage would like to grow fragrant, juicy grapes that can be boasted to experienced agronomists. However, in fact, this process is very troublesome, because for the season 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 the phylloxera of grapes is easily defeated if you recognize the enemy in time and begin to act correctly in a timely manner.
What does the leaf form of the disease look like
Detecting aphids is simple enough if you are careful and take a closer look at the plants. Specific galls on the leaves, reminiscent of warty formations of a spherical shape, indicate that there is a leaf phylloxera on grapes. If the swellings are noticeable only on the lower side of the green mass, then this is the primary infection of the bush, and if on the upper, then the larvae have already settled again.
It is worth noting that the intensity of phylloxera development on plants can be different and directly depends on the immunity of the bushes and their age.
So, if the phylloxera (growths on the leaves of grapes) are clearly visible with 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 sparse. Visually, the plant is simply oppressed, and in order to establish the exact cause of its disease, you will have to take samples more than once for a detailed study.
How to recognize the root form of the disease
In order to detect the presence of aphids or traces of its presence on the root system, you need to dig out a few suspicious vines or superficial roots. Experts recommend doing the procedure in the second half of the summer, because it is during this period that the pest multiplies actively and is easier to detect. Soil should also be present on the sample taken. Using a sharp thin knife or scalpel, carefully separate the lumps of earth and examine the contents of cracks in the cortex. If the phylloxera of grapes is present on them, then the winegrower will notice small swellings on small roots, and on thick ones - clusters of aphids resembling yellow spots. They will be roundish, not more than 1 centimeter in diameter. It is noteworthy that the affected root tips take a hooked or club-shaped form with yellowish-white nodules that darken over time, disintegrate, and then become almost indistinguishable. The bark resembles a sponge, crumbles, and the root itself looks dried out.
At the very beginning of the phylloxera disease on grapes, it is almost invisible and it can only be found in the fifth year, so the control excavation procedure will have to be done annually. It is important to remember that insects most often live in areas bordering the foci of infection, since completely diseased plants always leave and breed in healthy ones. The pest is able to settle both on the root surface and on the part located at a depth of a little more than a meter. For inspection, you need to choose samples taken on live bushes.
Homeland of phylloxera, when and where was revealed
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 the vineyards was recorded in 1868 in Europe. It is known from history that in the 19th century the phylloxera of grapes destroyed more than 6 hectares of plantations, and appeared in Russia in 1880. The great wine-grower V.E. Tairov noted that aphid is the most terrible and persistent pest, because it lives on roots and foliage, destroys bush after bush and brings only devastation and calamity everywhere. In the second half of the century, the pest appeared in the south of France and with extraordinary speed spread to almost all European regions.
It is worth noting that in a short period of time, phylloxera has destroyed over 70% of vineyards around the globe.
Root Pest Lifestyle
Grape aphids have an extremely complex life cycle and are divided into the following forms:
- underground;
- ground;
- providing communication (winged).
So, absolutely all individuals of aphids affecting the root system are exclusively female. Insects are distinguished by the absence of wings, a yellow-green color with small dark dots on the back. Their sucking proboscis extends from the head to the abdominal part of the trunk and is capable of piercing 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. A 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 lifestyle
In late summer - early autumn among the root aphids you can see nymphs - thinner orange individuals with buds 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 capable of flying short distances, laying unfertilized eggs on the grape buds, the underside of the leaf and the loose bark. Male larvae grow from smaller larvae, which live only up to 10 days, because they cannot eat due to the absence 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-shaped lifestyle
With the onset of spring, female wingless aphids hatch from a winter egg, which initially settles on 1-6 leaves. Gradually, she moves higher and higher, sucking all the juices from the top of the green mass. A green gall with a concave shape, sometimes with reddish spots, forms at the puncture sites. In just a few weeks, the phylloxera of the grapes lays more than 1000 eggs, of which in 8 days young individuals appear, settling on fragile shoots. The pest quickly creeps 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 the fallen leaves, such a phylloxera on grapes transfers control measures very persistently.
How phylloxera spreads
Grape aphids of root, leaf and winged forms are able to very actively move along green shoots, foliage and in the soil. Sometimes underground individuals find themselves on the surface, where they move for hours without food or rest at a speed of 3 cm per minute. Winged insects overcome up to 100 meters. Also, the phylloxera of grapes passively moves long distances with wind, mud, or rainwater. There are cases when the pest covered about 30 kilometers. The person himself, contributing to the infected grafting and planting material, treating healthy 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 dangerous phylloxera
In the course of its life, the phylloxera, first of all, affects the root system, so every year the bush receives less nutrients or completely ceases to absorb them. 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 up 3-5 years after the defeat, and more mature ones much later. The shoots of weakened grapes do not have time to ripen, so often they do not tolerate winter frosts.
If we consider the lesion focus, 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.
What grape varieties are best planted on the site
Since the pest mainly lives on American grape varieties, experts recommend growing European plant species by planting them in the sands. It is also rational to switch to complex-resistant new varieties or hybrids of Save-Villar. It is also reliable to use European grape varieties resistant to phylloxera at the time of inoculation.
Recommended varieties of rootstock vines:
- Cober 5BB;
- Riparia x Rupestris 101-14;
- Riparia Gluard.
The roots of these plant species are resistant to decay and do not die at the time of phylloxera infection.
Folk methods of dealing with phylloxera
After the phylloxera of grapes has been identified, the fight against it should begin immediately. If the spread of the pest is insignificant, then you can completely do it with improvised means. 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 are advised to prepare a variety of types of solutions:
- Soapy (dissolve 100 g tar soap in 10 l of water). It is possible to mix soap with a small amount of washing powder and detergent, but it is better to avoid too aromatic preparations, since they attract insects.
- From ash (1 cup per 5 liters of water and insist for 12 hours).
- From the peel of citrus fruits (0.5 liters of the crushed substance, boil in 1 liter of water, filter and add another 10 liters of liquid).
- From the tops of solanaceous plants (half fill a 3-liter bottle with finely chopped herbs and pour boiling water over the neck. Insist for a day, then add 1 tbsp. L soap soap or powder).
- Tobacco (brew 1 cup of tobacco leaves in 5 liters of water, insist and strain).
In addition, many experienced growers are advised to attract beneficial insects, birds to the plantation and plant aromatic herbs or flowers near the bushes.
