What is a gall midge on raspberries: a photo of a pest, ways to get rid
When growing raspberries, a gardener may encounter a problem - wilting or brittle shoots. The reason for this is a miniature insect called a gall midge. What is it and how to deal with a pest - in more detail later in the article.
Gallitsa - raspberry pest
The insect is distributed around the world. Gall mosquitoes, as the pest is also called, in nature there are about 6,000 species. Raspberries were chosen by two of them: shoot and stem.
Did you know? Growths, formed on the petioles of oak foliage by some gall pests, was once called "ink nuts": they used to extract the basis material for written ink.
Both species are dipterous; their bodies do not exceed 4 mm in length. Long antennae and thin legs give a resemblance to an ordinary mosquito. The adult shoot gall midge is lighter or with a brownish tint, the stem variety is painted black.
The larvae of individuals differ in appearance:
- shoot - body 10-12 mm long, with a yellow or green tint;
- stem - 1–2 mm long, body surface orange or pale yellow.
The life cycle of insects has practically no differences: the activity of females begins in May-June, during the flowering of raspberries. For 3 days (life expectancy), the mosquito manages to postpone the offspring.
The shoot gall midget lays eggs on fruit-bearing shoots, and the stem gallium lays on the branches of young root shoots. Inside the stem, larvae are born that feed on the sap of the plant. Due to the substance secreted by the larvae, biting into the flesh of the shoots, the so-called galls are formed on their surface - growths or swelling of the trunk. In the shoot mosquito, they have a circular shape, in the stem, they resemble an elongated cone.
Larvae of a shoot pest are selected from the stem and curled into a cocoon in the soil, near the roots of raspberries. The stem larva hibernates in a cocoon in the outgrowth formed by it on a branch. In spring, the larvae pupate, and the imago is already looking for damage or cracks in the shoot bark to postpone new offspring.
The raspberry mosquito larvae feed on the sap of the plants, biting into the pulp, they turn the inside of the stem into dust. From the slightest blow of the wind, such an escape breaks down, unable to withstand the load. The more individuals settled on raspberries, the faster it starts to dry, not getting enough nutrition.
Important! The shoot gall midge is considered especially dangerous, since its larvae wintering in the soil can spread over a large area, destroying the entire raspberry.
If the bush survives until winter, and the gardener does not detect pest outbreaks, branches with damaged tissues will not tolerate winter. Most offensively, when a bush dries, strewn with unripe fruits.
Thickening resulting from the life of the insect larvae is an open area for the penetration of fungal spores. As a result, the entire raspberry can be infected with anthracnose or gray rot and other diseases
Ways to combat the gall midge
You need to get rid of raspberry mosquito or prevent its mass reproduction in raspberries twice a year. In the spring, until the flight of the pest, about in the early to mid-April, conduct inspection and spraying with protective equipment. Much attention is paid to the lower parts of the stems and young, newly formed shoots. The same work must be repeated after the harvest, when the plants are prepared for winter.
Important! When working with chemicals, precautions must be observed, especially skin and mucous membranes should be protected.
Chemicals are used before the period of active flowering, so that the active substances do not accumulate in future berries. The following insecticides are popular and effective:
- "Arivo" - a drug with contact-intestinal action, effective against a large number of adult insects and their larvae. For spraying, a solution is prepared in a proportion of 1.5 ml / 10 l of water, the procedure is carried out in dry, clear weather. The protective effect lasts 14 days.
- "Spark" - the fight against possibly wintering larvae begins before the formation of flower buds begins. To prepare the working solution, 1 liter of warm (+ 40 ° C) water is needed, 1 tablet of the drug, wrapped in tissue, is lowered into it. The insoluble residue of the product remains on the tissue, and the resulting mixture is brought to the desired volume (8 l).
- "Karate" - shoot processing is carried out in the morning or in the evening with a solution prepared in the proportion: 1 ampoule per 1 liter of water, the mixture is brought to a volume of 10 liters. After spraying, the result is visible after half an hour.
- Confidor - the drug is preferred, since the active substances, circulating in the tissues of raspberries, help her recover from the lesion. After treatment with an insecticide, the affected shoots of plants do not lag behind in development from healthy branches. The protective period of the drug lasts up to 3 weeks. The drug is diluted in a proportion of 1 ml / 10 l of water.
Before applying folk methods to protect raspberries, you need to understand that they are effective in small amounts of pests. Popular tricks:
- Dusting with mustard powder the entire plot with the crop and applying it to the soil. Watering the soil with an aqueous solution of mustard: 200 g of powder / 10 l of water.
- Spraying plants with infusion of tansy, wormwood (dry grass 350 g / 10 l of water). First, the dried grass is boiled in 1 liter of water, then the cooled mixture is added to the desired volume and insisted for 12 hours.
Prevention of the appearance of gall midges is vital in raspberries. Chemical treatment, and folk treatment as well, kills only adult insects and feeding larvae. Eggs and pupae in most cases remain unharmed, therefore, prevention begins with constant loosening of the soil: in spring, throughout the season and deep digging in the fall.
Mechanical preventive measures are considered sanitary pruning raspberries. After winter, cut off all shoots that are damaged by frost, wind or mechanically. This will prevent the mosquito from finding a weak spot on the bark for masonry. Often, the gall midge in the initial stages of the lesion can be eliminated by simply removing the bloated branch where the offspring is located. The trimmed parts are disposed of, and the bushes are sprayed with an insecticide.
Did you know? Some pests, such as the gall midge of aphidyme, are used as a biological method for controlling aphids on crops.
The method of repelling insects using repellent plants, such as wormwood, garlic or nasturtium, has long been known. Part of the plants is planted in the aisles, part - around the raspberry.An effective form of protection is to cover the ground with a thick layer of mulch. In addition to its usual function of protecting roots from overheating and drying out, the material will restrain the emergence of young adults
Thus, if you know the enemy "in person", get acquainted with drugs and other methods of protection, then it is quite possible to protect your crop. The gardener is more likely to observe crop rotation, agricultural practices and preventive measures.