Blackcurrant grows and bears fruit on every garden plot. Its beneficial properties are undeniable. But like other garden crops, it is susceptible to a variety of pests, including Cecidophyopsis ribs. the following article describes different methods and control measures to protect the berries from pest attacks.
WHAT IS CECIDOPHYOPSIS RIBIS?
Cecidophyopsis ribis refers to the four-legged Cecidophyopsis ribis. it is often referred to as blackcurrant gall mite or big bud mite. they are extremely difficult to see because of their tiny size. Adult female Cecidophyopsis ribis have an external size of 0.2 mm, and male Cecidophyopsis ribis are even smaller.
The body of Cecidophyopsis ribis is white, worm-like, elongated, and rounded, with four legs. The legs are made up of segments, hence the name arthropod. cecidophyopsis ribis suck the sap from plants with their stinging, sucking mouthparts that lead them to their death.
THE DEVELOPMENTAL CYCLE OF CECIDOPHYOPSIS RIBIS
Fertilized females of Cecidophyopsis ribis overwinter in the bud. An enclosed shelter protects them from winter frosts and other weather hazards.
In spring, when the air temperature reaches 41°F (5°C), females of Cecidophyopsis ribis begin to concentrate on egg production. A single female plant is capable of laying about 8,000 eggs. A single bud can hold 3 to 8,000 eggs at a time, causing the bud to swell and become similar to a small pea. Such peas look like crushed cabbage shoots in a cut.
The larvae of Cecidophyopsis ribis last for about 6 to 12 days. The voracious young specimens penetrate the healthy buds through the cracks in the head and start feeding during the flower bud bloom. Sucking sap from young buds, flowers and plant shoots leads to the death of undeveloped plant organs. young females and larvae of Cecidophyopsis ribis for about a month, coinciding with the beginning of flowering and mass flowering. During this period, they can be seen with the naked eye. The voracious swarms of pests are carried by wind, clothing, and rain to other bushes.
HOW HARMFUL IS CECIDOPHYOPSIS RIBIS?
Depending on the degree of damage, Cecidophyopsis ribis belongs to the group of very dangerous pests of horticultural fruit crops. In one year, one female Cecidophyopsis ribis produces 5 generations (2 spring and 3 summers and fall), which makes about 150-400 thousand pests.
During development, Cecidophyopsis ribis has adapted to tolerate climatic catastrophes in sheltered conditions (buds, shoots, galls, etc.), which complicates the control of these pests. The developed adaptations are so reliable that berry crops (blackcurrant, red currant, white currant, and gooseberry) may perish within a season without radical protection measures.
Signs of Cecidophyopsis ribis infection
Cecidophyopsis ribis mainly affects the flower buds of the plant. In autumn, deformed, damaged flower buds increase in size and begin to differ in appearance from healthy ones.
After autumn leaf fall, two types of buds can be clearly distinguished in currant bushes affected by Cecidophyopsis ribis
- healthy buds with round elongated normally developed buds and elongated leaf buds covered by dense external scales.
- diseased ones are swollen, rounded, and resemble an exserted miniature cabbage head. They are swollen by large numbers of overwintering, sexually mature females of Cecidophyopsis ribis, which are ready to reproduce with the arrival of warm weather.
In spring and summer.
- The change in shape, size, and color of the leaves at the top of the young shoots is striking.
- Leaves become rough, leathery to the touch, light in color, and possibly deformed.
- The shoots stop developing. The witch’s broom appears on the stem. It infects the plant virally and its carrier, along with other pests, is Cecidophyopsis ribis. they are carriers of viral diseases such as leaf reversal and swelling of flowers. There is no treatment. Diseased plants are destroyed.
CONTROL MEASURES OF CECIDOPHYOPSIS RIBIS
Fighting germination Cecidophyopsis ribis is very difficult, it spends almost its entire life inside the buds. When the vulnerable larvae migrate, the maximum number of larvae can be eliminated by treating them with insecticides.
However, considering the placement period (germination and flowering), treatment is strictly forbidden because of the presence of beneficial insects (bees, bumblebees) pollinating at this time. This is why the budding Cecidophyopsis ribis is known as a particularly dangerous pest. The technique of active elimination of budding Cecidophyopsis ribis is carried out during the period before flowering and after harvesting.
All types of control of Cecidophyopsis ribis on currants can be divided into.
- Agricultural techniques.
PREVENTION OF TRANSMISSION OF CECIDOPHYOPSIS RIBIS
Preventive measures against Cecidophyopsis ribis include
- Keeping the site weed-free.
- Clearing berry patches from fallen leaves.
- Compulsory hygienic pruning in autumn and spring.
- Use only healthy planting material for propagation.
AGRICULTURAL TECHNICAL MEASURES
Timely watering, feeding, and treatment of plants to increase their immunity to pest attacks.
Use only regionalized, pest-resistant varieties for planting and propagation.
It is very important that the planting material is not infested with pests. To prevent pests, you can drop seedlings or rooted plugs completely into a working solution consisting of agarwood (10 g) and colloidal sulfur (40 g) in 2.5 Gal (10 l) of water for 18-20 hours.
Rooted seedlings and shoots can be placed in hot water for up to 104-113°F (40-45°C) for 15 minutes prior to planting.
Sprouting Cecidophyopsis ribis larvae do not tolerate high air humidity. You can take advantage of this property by giving the berries rain when the hatching larvae (first generation in spring) are first placed.
Treat black, red, and white currant bushes (only currants) with fire on dormant buds in early spring (early March) every year.
Implementation of the procedure. After sanitary and thinning pruning of currant bushes, spend 2-3 times from top to bottom with a blowtorch or gas burner at a distance of 3-4inch (8-10 cm) without stopping so as not to burn the branches. Heating with fire will kill aphids and most Cecidophyopsis ribis without damaging the plant.
Fire will not damage healthy flower buds covered by dense top scales. Diseased buds are loosened and the cover is torn by the pest laying eggs of future offspring that have overpopulated the buds.
During this period, they are so fragile that fire (elevated temperatures) can burn and cause the death of unwanted “houseguests”. Of course, not all females are killed by this method, but their activity is drastically reduced.
During the same period, instead of fire treatment, currant bushes can be “bathed” with a hot shower, spending 1-1.5 buckets of water per large bush.
Perform the procedure. For bush treatment, it is more convenient to use a waterer with sprinklers. Pour boiling water into a container. Wash the bush from a height of about 6-8inch (15-20 cm) above the bush.
At low air temperatures, hot boiling water will cool to 140-158°F (60-70°C) as it fills the watering can and the water reaches the bush. Such temperatures will not damage the plants but will destroy some pests (acting on the same principle as fire treatment) and fungal infections.
PHYSICAL DAMAGE OF CECIDOPHYOPSIS RIBIS
During spring pruning, each currant branch should be carefully examined. If there are 1-2 swollen buds on the branch, cut them off, put them in a bag and burn them. If the number of swollen buds is 4-6 and they are scattered on the branch, it should be cut off and burned.
This physical destruction of Cecidophyopsis ribis is effective, especially if this procedure is carried out every year in spring and autumn.
Use of chemicals and other drugs to eradicate Cecidophyopsis ribis
The following methods of eliminating Cecidophyopsis ribis are not safe for owners, their families, pets and birds. Therefore, before using insecticides to kill Cecidophyopsis ribis, it is necessary to be well prepared to study the effects and after-effects of chemicals, their effectiveness, repeated applications and implementation of technical recommendations, according to specialized literature.
Frequency of treatment
Non-compliance with the instructions for the use of the preparation reduces its effectiveness to zero.
The developmental cycle of Cecidophyopsis ribis depends on the external temperature. the first active development of Cecidophyopsis ribis larvae begins at an air temperature of 50-53°F (10-12°C), but their emergence and placement may occur after 25 days until the air temperature reaches 64°F (18°C).
The higher the air temperature, the shorter the time for carnivorous larvae to develop from eggs, and they infect new shoots of native and neighboring shrubs (Table 1).
Table 1: Treatment intervals for preparations against Cecidophyopsis ribis
|Air temperature, °F||Developmental period, days||Treatment interval, days|
The number of treatments in the temperature interval should be at least three.
- First: Treatments are to eliminate overwintering adult females of Cecidophyopsis ribis and hatching larvae (resistant to cold). Some eggs do not have time to go through the developmental cycle.
- Second type: the larvae complete their developmental cycle with the arrival of warmth. If the treatment interval is not observed (treatment of the bush is delayed), the larvae have time to transform into adults and lay a second clutch of eggs.
- third: treatment is safe. surviving young females of Cecidophyopsis ribis may lay eggs and thus cause a new outbreak of the bush work.
It is particularly important to record the first resettlement of Cecidophyopsis ribis larvae during the budding period. During this period, they are visible to the naked eye. After treating the bushes, temperatures were further monitored and treatment intervals observed. For example, maintain temperatures in the range of 68-77°F (20-25°C) – treatment intervals of 8-10 days.
USE OF INSECTICIDES FOR THE CONTROL OF CECIDOPHYOPSIS RIBIS
The “enthusiasts” of quick measures have the possibility to offer several chemical preparations for the treatment of plants.
Cecidophyopsis ribis belongs to the group of spiders, so they are not destroyed by insecticides, but by acaricides and insecticides.
Please note! The use of chemical agents, if used improperly, can be harmful to health. Therefore, it is necessary to.
- observe personal safety measures (gloves, goggles, headgear, respirator or multi-layer dressing, gown)
- Follow the instructions in the instructions.
- It is recommended to use the product alternately in spring and autumn to avoid addictive effects.
The most vulnerable period for Cecidophyopsis ribis is when the larvae move to a new location. The first wave of hatched Cecidophyopsis ribis larvae moves to open spaces during the leaf germination and flowering stages.
Their movement to the new territory lasts 2-3 weeks. It is during this period that at least 2 sprays must be made at intervals of 8-12 days.
From the insecticides used against Cecidophyopsis ribis during this period, the following acaricide preparations are used.
- Envidor (Spirodiclofen).
- Forbid 4F.
The next period for the use of insecticides for the control of Cecidophyopsis ribis is the treatment of the bushes after the complete harvest (so that the children do not eat the last berries that are so delicious in the bushes).
It is recommended to use more potent acaricide formulations at this time.
- Compo Bi 58;
- Nitrobenzene (Nitrobenzol).
TREATMENT OF CECIDOPHYOPSIS RIBIS WITH SULFUR PREPARATIONS
Among the sulfur preparations used to control Cecidophyopsis ribis are colloidal sulfur (Sulfarid) and carbosulfur. The bushes and the surrounding soil can be treated until the end of flowering. A solution of colloidal sulfur is prepared at the rate of 10 g of drug and 75 g of carbophos per 2.5 Gal (10 l) of water.
Far from being a harmless agent, sulfur can cause young leaves to burn and fall off at the doses used. Therefore, re-spraying (after flowering) should be done with a solution 2 times less concentrated. The most efficient treatment of currant bushes is done with a colloidal sulfur solution at a temperature of not less than 68°F (20°C).
Currants form a harvest in a short time and the drug effect can last for a long time. Therefore, chemical preparations are used only once, only at the budding stage and at the beginning of mass budding. Further use of insecticides is prohibited. In the process of pest eradication, it is necessary to transition to the use of means that are less harmful to human health.
USE OF BIOLOGICAL AGENTS AGAINST CECIDOPHYOPSIS RIBIS
Such means can be used as biological insecticides. They are based on positive strains of fungi and bacteria and are harmless to humans. In addition to a whole host of positive properties of biocides and biopesticides, their application has limitations. The main one is that the drug is effective at high temperatures 59-66°F (15-19°C).
They are useless in windy, cold weather, which is often the case in early spring. If spring comes early and temperatures are high, the use of acaricide formulations is highly efficient.
Among biological insecticides, the most famous is.
The interval of application of preparations depends on the ambient temperature until the end of flowering and after harvest. These preparations should be alternated. In-tank mixtures with bio fungicides have good compatibility.
However, check the compatibility of the formulations, especially new ones, before preparing the tank mixture. Dilution and handling methods are indicated on the package. Do not deviate from the recommendations and do it yourself without success.
More related information about Garden Pests