If dark red growths appeared on the leaves of currant, this is an alarming sign: plants are affected by leaf gall aphids.
What Is Gall Aphid?
A common sucking pest that most often infects young currant leaves. Aphids inhabit the underside of leaves, forming fairly large colonies, and manifest themselves on the appearance of so-called galls on the leaves – convex outgrowths of a dark red color. As the leaf ages, galls may become yellowish or greenish. With a severe defeat, the leaves dry up and die off, the growth of shoots is inhibited. The size of adult aphids is 2.2 – 2.5 mm; the color is from lemon yellow to brown. Eggs laid in autumn hibernate in cracks in the cortex near the kidneys. Pest hatching begins rather early during leaf blooming. External signs of damage – galls – appear on the leaves during the formation of the ovaries.
The largest number of pests reach in June. The flight of winged females begins at the beginning of summer and reaches its highest point in July when aphids move to weeds, where they feed until autumn. Then the females return to the current for laying eggs. Flightless individuals can remain on the current all season. Over the summer, several generations of aphids hatch in the middle lane (up to 8).
How to Deal With Gall Aphids?
- Timely weeding of weeds.
- Spraying plants in early spring with 3% Bordeaux fluid (also for the prevention of anthracnose).
- Processing before budding of the kidneys with insecticidal drugs (“Prophylactic”, ” Spark double effect”).
- Attraction to the garden of predator insects that feed on aphids (ladybugs, lacewing, camels).
- To destroy wintering pests, it is recommended that the bushes and tree trunks be surrounded with very hot water (+80 … + 90 ° C) before the sap flow begins.
Folk Remedies for Gall Aphids on Currant
With a small lesion, damaged leaves and shoots are cut and destroyed. If the pest is small, you can try to cope with it with folk remedies.
- Infusion of marigolds. For 5 liters (half a bucket) of dry crushed marigolds take 10 liters of water and 50 g of laundry soap. The raw materials are poured with hot water, insisted for 2 days, then mixed with soap and plants are sprayed.
- Laundry soap solution: 300-400 g of soap is dissolved in 10 l of water.
- Infusion of tomato tops and onion peels. For cooking, you need 0.5 kg of onion husks and 1.5 – 2 kg of tops or stepsons of tomatoes. Leaves are brewed with 5 liters of boiling water and insisted for about 4 hours, then boiled for 3 hours, filtered and added water in a ratio of 1: 2. The husk is poured with hot water (approx. 2 liters) and insisted for no more than two days, after which another 2 liters of water and a little liquid soap are added. After that, both infusions are mixed.
- Infusion or decoction of tobacco dust.
When using natural products, 2-3 treatments are required after 7-10 days. Processing is carried out in dry, calm weather; if after some time it rains, spraying must be repeated.
With an average degree of damage, if folk remedies did not help, it is recommended to use insecticides on a biological basis: Biotin, Fitoverm, Agravertin. These drugs are considered one of the safest and can be used throughout the growing season.
If the plantings of currants suffer greatly from gall aphids, you will have to resort to chemical insecticides. Drugs show high efficacy “Aliot”, ” Kinmiks “, ” aktellik “, ” konfidor “, ” Intal sup ” et al. Usually 2-3 necessary processing, the interval between them is indicated in the instructions to the drug.