Gall aphid on currants: control measures

Gallic aphid also has the name redcurrant gallic aphid, and from the very name it becomes clear that this pest is closely related to currants. It is this shrub, ubiquitous in our summer cottages, that is most often attacked by gall aphids. In this article, we will mainly talk about how to protect currant bushes from the aforementioned aggressor.

What is the purpose of processing currants from gall aphids?

The gall aphid feeds on the juice that it sucks from the leaves of the currant. In an attempt to protect its leaves from the "wounds" inflicted by aphids, the plant tightens the affected areas with a special tissue. The leaves after the gall aphid do not look at all attractive, outwardly they are all covered with mounds, similar to peculiar growths, and on the back of the leaf, if you look closely, you will see the perpetrators of this misfortune themselves. The growths that appear on the affected leaves are called galls, here's an explanation of the name of the pest.

Young, succulent leaves that have appeared in the current season are the very first to be attacked, which means that next year's harvest is under threat as well. This is due to the fact that the damaged parts of the bush stop their development.

If the gall aphid is too severely affected, the currant can even dry out completely if it does not have enough energy to heal all the wounds.

In addition, through bites in the leaves, aphids are able to carry various infectious diseases, and a plant affected by aphids decreases resistance to diseases, which ultimately can also lead to disastrous consequences.

It is worth noting that red, white, burgundy currants are most susceptible to the attack of gall aphids, and this pest does not like black and golden. Such gastronomic preferences are due to the fact that the leaves of black (and golden) currants are much tougher than those of other species, which means that it will be more difficult to bite into them.

In the absence of currant plantings in the place where aphids appear, this pest can feed on the juices of such plants as mint, sage, oregano, lavender, thyme, purse. This fact is worth remembering and try not to plant these plants near currant bushes.

Description of the pest Gall aphid

The fight against gall aphids on currants is widespread among gardeners everywhere. There are more than four thousand of its subspecies in the world. Outwardly, it is very similar to its congeners, other species of aphids. It is a small insect (only 2mm in length) with an oval body, on which there are small hairs, yellowish-green in color, mostly without wings.

During one summer season, up to twenty new generations of these insects appear. That is, only one representative of the gall aphid is capable of producing offspring in the amount of more than 100 specimens! Moreover, the number of emerging offspring is directly proportional to the air temperature. The hotter the summer, the more pests will be.

Leafy gall aphid on red currant and its life cycle

The life cycle of the gall aphid is also quite interesting from the point of view of biology. The gall aphid is divided into several groups, which are very different from each other in their vital activity. A group of founding aphids emerge from laid eggs. These representatives of aphids are, as it were, the progenitors for the rest.They themselves no longer lay eggs, but produce live individuals, and only female individuals are born, which in the future will produce the next generation of aphids.

The most common group of aphids are females that do not have sexual intercourse, however, those that are parthenogenetic give birth to their own kind. This group of aphids is wingless, and, therefore, is able to move exclusively within the framework of the "mother" plant.

Another group is called the settler. These representatives of aphids have wings, and they fly to other plants when the number of aphids has grown so that the existing food supply is coming to an end. On new plants, this aphid reproduces the next generation, and the colony of aphids continues to develop already in this place.

Striped aphids are, as it were, an intermediate generation and can be males or females without wings. They can have sexual intercourse and lay fertilized eggs.

The generation of bisexual aphids is responsible for species survival, laying eggs everywhere (for example, on weeds nearby to currant bushes). It is from such eggs that the founder's aphids appear. Eggs can rest for more than 250 days, just before warm days. In spring, the founder's aphids are born from these eggs, and they are placed on currant bushes.

The main breeding peak of aphids is the time of flowering of currants, and the most serious damage to aphids is inflicted on plantings from early to mid-June. Further, the leaves of the currant cease to be juicy and become unsuitable for feeding on aphids. Then individuals capable of moving move to other plants (mint, sage, oregano, etc.). Already on these plants, individuals appear that have both male and female sexual characteristics. In the second half of August, these specimens will again move to the currants, where they will lay their eggs.

Gall aphid photo

Gall aphid on red currants: how to fight?

If the spread of aphids has not reached a mass character, that is, only a few leaves are affected (or, for example, one branch), then the affected leaves (twig) can simply be torn off and burned (the branch cut must be processed).

Folk remedies for gall aphids

In the fight against a pest, you can use the proven "old-fashioned" methods. Such funds usually do not harm the currant itself in any way, and also do not affect the safety of the crop.
The most popular remedy in this category is tobacco dust infusion. 300 g of tobacco dust is poured with 10 liters of water, brought to a boil and, tightly closed, left in a dark place to infuse for 3 days. Then strain the infusion, add a little soap (so that the liquid does not wash off the leaves longer) and treat the affected plants, especially on the inside of the leaf, at the point where the aphids are directly attached. This procedure is carried out as needed throughout the summer (after 5-6 days), excluding the moment of flowering and direct harvesting.

Another popular method is the infusion of marigolds, which requires a large number of flowers. 500g of flowers are crushed, 10 liters of water are added, brought to a boil, closed and left in a dark place for a couple of days. After 2 days, the resulting infusion is filtered, soap is added and the plants are also treated from the lower sides of the leaves.

Such processing can be performed with the same frequency as the processing with infusion of tobacco dust.

Gall aphid: how to treat it chemically?

If it was not possible to cope with the invasion of gall aphids on currants using folk methods, biological preparations are used. Their active substances are bacterial spores, various parts of fungi, elementary viruses. These substances poisoning the insect organism penetrate into their digestive system together with the juice of the processed plant and cause their death.

So, how to spray a gall aphid? The most popular biological agents for aphid control are Bitoxibacillin, Aktofit and Avertin. They must be used strictly following the instructions, because this is still not a harmless herb infusion. When working with these drugs, you should not ignore personal protective equipment (respirators, gloves), and carry out the processing in the absence of wind.

There are, however, cases when it is no longer possible to do without the use of harsher insecticides. In such a situation, such gall aphid remedies as Aktelik, Confidor Maxi, Vofatox, Calypso, Proteus are suitable for use.

As a rule, treatment with such preparations is carried out in the spring, during bud break, which is advisable if your currants were subjected to the strongest attack by aphids last summer, or after harvest, when the damage caused by aphids this summer is obvious.

While working with such products, it is necessary to carefully study the instructions, choosing the correct dosage of the drug, and also pay attention to the processing time of the plant (early morning or late evening, since most chemicals cause fatal harm not only to aphids, but also to other beneficial insects, including bees).

And, of course, the use of personal protective equipment is strictly required.

Leaf gall aphid: preventive control measures

It is always easier to prevent a disease than to cure it later. This statement is also true for preventing the spread of gall aphids in your area.

They begin to carry out preventive treatments of currant bushes from aphids at the very beginning of spring, before the buds open. In this case, the treatment is aimed at destroying the clutches of aphid eggs.

For such processing, a drug called Nitrafen is suitable. 4 ml of this product is dissolved in 10 liters of water and the resulting solution is treated with the bushes and the area around the bush through a diffuser. The working solution is enough for 20-40 currant bushes (depending on their size).

You can repeat the treatment in the fall, after dropping the foliage.

In order to destroy eggs, ordinary boiling water can be successfully used in early spring. The water is brought to a boil and, with the help of a watering can (better, of course, a metal one), the bushes are watered. Such treatment is carried out at the stage of kidney swelling.

As a preventive measure, you can also plant crops such as marigolds, chamomile, calendula near the plantings of currants. Be sure to clear weeds throughout the growing season. Pay special attention to the absence of such a weed as the purse, it is he who is a kind of "manger" for the further development of aphids.