Pests and diseases of the rose. Means of protection
Diseases and pests cause severe damage to roses, and sometimes lead to their death. Timely and correct implementation of agricultural techniques and protective measures forms the basis of preventive plant protection. In this article we tried to collect information about all the most common diseases and pests of roses and, of course, provided the reader with a complete list of the arsenal of dealing with them.
Before starting the prevention of culture from diseases and pests, you need to remember your health. To preserve it, pesticides (pesticides) should be applied, observing elementary rules: use respirators, rubber gloves, use drugs only in the prescribed doses. After treatment, wash hands and face with soap and water.
- Pests of roses
- Rose diseases
- Preparation of spray solutions
- Folk remedies for roses
Pests of roses
The most dangerous pests during the growing season of roses, when buds, leaves, shoots and flowers develop on bushes that serve as food for larvae or adult insects. Plants are especially in need of protection at this time.
Among the gnawing pests for roses, the most dangerous are beetles, caterpillars and sawfly larvae. They violate the integrity of organs, slowing the growth and development of bushes, reducing flowering. Damage by gnawing insects boils down to the following: coarse or perforated eating of the pulp, leaving the veins intact;
- curly eating of leaves from the edges;
- mining, that is, eating inside the tissues of the leaves of the courses;
- gnawing in the stems of moves;
- damage to buds and flowers outside;
- the destruction of stamens and pistils.
The oral organs of sucking pests are adapted to suck out liquid food. They pierce the tissues and suck out the cellular juice, causing a disturbance in physiological processes. From such damage, the leaves turn yellow, curl, dry out and die. Particularly common sucking pests of roses include ticks, aphids, scale insects, cicadas (whitefly rosacea). The listed pests can appear both in open and protected ground.
Settles on rose bushes in large colonies, located on the underside of leaves, on the stems of young shoots, buds and peduncles. Aphid larvae are very small, barely visible to the eye. They quickly turn into wingless large female founders, which hatch at once about a hundred larvae, the latter, in turn, after eight to ten days are able to give new offspring. Only ten or more generations per year.
According to the Swiss grower S. Olbricht, the generation of one aphid during the growing season can produce about two million individuals. By the end of summer, winged aphids appear - males and females. They lay fertilized wintering eggs, from which new aphid colonies emerge in early spring.
Sucking juice from young organs of roses, insects grow and multiply rapidly. Bushes weakened by aphids do not grow well, shoots often bend, leaves twist and crumble, and buds do not open or give ugly flowers. Roses, weakened by aphids, tolerate wintering conditions worse.
The appearance of aphids on roses can be judged by the increased activity of ants in the rose garden, which drink the sweet juice secreted by aphids. Ants protect aphid colonies and even organize new colonies, transferring the female founders to places not yet populated by pests. Aphids are readily eaten by seven-point ladybugs. One of them can eat up to 270 aphid larvae per day.
Rose aphid control measures: treatment in early spring before swelling of the kidneys with contact insecticides. Later, one of the following insecticides is used: actellic, anti, karbofos, methation, horn and others.
Spraying with a solution: 2 g of kerosene in 10 l of water.
An infusion of the following composition is also effective: 300 g of chopped onion or garlic and 400 g of tomato leaves are placed in a three-liter jar. The latter is filled with water and put in a warm place for 6 hours to insist. After this, the infusion is mixed well, filtered through gauze or a fine mesh and in a large bowl the volume is brought up to 10 l with water.
So that the infusion sticks well to the leaves and shoots, add 40 g of 72% soap, but better - liquid green. This infusion is treated with bushes every seven days in a fivefold repetition. It can also be used against ticks, tinkers, sawflies, caterpillars.
Pay attention to our detailed material: Aphids on roses and pest control methods.
Widespread and causes great harm to the culture. The leaves are covered with small white dots, become like marble and lose their decorative effect. Severe damage by cicadas leads to premature yellowing and falling of leaves. In the fall, the female lays eggs at the ends of the shoots of roses. In spring, larvae emerge from the overwintered eggs (they can be seen on the underside of the leaves). These are white small, inactive larvae that feed on leaf juice. The body of the circus is white or pale yellow, elongated. Adults are very mobile. At the slightest touch to the sheet, they quickly jump and fly to another place. Two to three generations develop annually.
Measures against rosacea: control of cicadas is most effective during the mass emergence of larvae. It is recommended that two treatments with insecticides with an interval of 10-12 days with the capture of the territory adjacent to the stands.
Drooling pennies, or omnivorous cicadas
The body of the adult insect is yellow-gray. Larvae live in their foamy secretions in the form of salivary foam, suck the juice from the stems. They are located in the axils of the leaves and on their lower side. When touched by the leaves infested by the pest, the larvae quickly jump out of the foam and hide.
Measures to combat slobbery pennies: spraying with insecticides.
Spider mite on a rose
One of the most dangerous pests of roses, especially in greenhouses, where it can develop year-round. Adult mites have four pairs of legs, their body is oval, 0.3-0.5 mm long, greenish yellow with black spots on the back. Winter body color - orange or red. Larvae are greenish with three pairs of legs. The eggs are small, up to 1 mm in diameter, round, transparent, located under a thin web. One female lays up to 180 eggs. Five to seven days later, larvae emerge from the eggs. The whole cycle of tick development is 10-25 days. An adult tick lives 18-35 days.
Both adult ticks and their larvae damage the leaves of roses on the underside, causing a sharp violation of physiological functions and metabolism. Pests suck the juice from the leaves, the affected leaves turn yellow, become covered with small bright spots at the injection sites and fall prematurely. The cobwebs and excrement secreted by the pests pollute the leaves, a lot of dust lingers on the latter. As a result, roses lose their decorative effect.
Females overwinter, mainly under plant debris, in greenhouses - under lumps of soil and in other secluded places. In spring, at an air temperature of 12–13 ° C, females lay barely noticeable transparent cream eggs on the underside of the leaves. In winter greenhouses, ticks live and breed constantly.
Often inexperienced rose growers complain of the yellowness of rose leaves, attributing to the plants various diseases (chlorosis, etc.). In fact, this is the work of spider mites. You can detect them with a magnifier.
Measures to combat the spider mite on a rose: spraying plants with axex at a concentration of 0.08% or with isophene - 0.05, omait - 0.1% and other acaricides. The development of ticks is restrained by spraying cold water on the lower surface of the leaves 3-4 times a day.
In closed ground conditions, the avermectin group preparations are most harmless: actofit, phytoverm, vermitek. These drugs do not affect eggs and non-moth-eating, waiting for molting, larvae and protonymphs of the tick. At a temperature of + 20 ° C, at least 3 treatments with an interval of 9-10 days are required. At + 30 ° C 3-4 treatments with an interval of 3-4 days.
The caterpillars of the three species of rosette leaflets and the fruit leaflet cause great harm to the leaves and young shoots of roses. The first caterpillars appear early in the spring, damaging barely blossomed buds, then young shoots and leaves.
Measures to combat rose leaves on a rose: with a small population of leaflets, the caterpillars are collected by hand and destroyed. In the spring, before the buds open, they spray the bushes with one of the pesticides.
There are two types: the Belt sawfly and the downward sawfly. The most common top-down sawfly. False caterpillars, or sawfly larvae winter in cocoons in the soil. In the spring, they pupate, and adult insects fly out of the pupae. The length of the adult insect is up to 6 mm, its back is shiny, black, wings are darkish, legs are black, legs are yellowish. The sawfly somewhat resembles a bee in structure. Females lay eggs one at a time on the tops of young shoots. Leaving the eggs, the caterpillars bite into a young shoot, make a move up to 4 cm long inside it (from top to bottom) and develop there. A damaged shoot darkens and dries. In autumn, the caterpillars descend into the soil for wintering.
Measures against rose sawflies: in the autumn they dig the soil under the bushes so that the pseudo-caterpillars are on the surface and freeze in winter. Against spawning caterpillars, plants are sprayed with one of the pesticides. Pruning shoots are trimmed and burned before larvae emerge from them.
Bronze and deer
Bronze beetles on top are golden green in sparse hairs, below are copper-red. The length of their body is 15-20 mm. Beetles fly from May to August. Females lay eggs in humus-rich soil in manure. At the end of summer, larvae pupate in the soil, beetles emerge from them, which winter there and fly out next summer. Deer - black beetles densely covered with grayish hairs with white spots, body length of the beetle is 8-12 mm.
Both beetles eat petals of rose flowers, eat stamens and pistils. Flowers of light tones suffer more from them.
Control measures: picking beetles early in the morning when they are still sitting on flowers.
Under adverse conditions (lack of light, moisture, mineral nutrition or an excess of nitrogen fertilizers) roses weaken. This reduces the resistance of plants to many diseases and to the settlement of pests. Sometimes roses are so oppressed that they die. The sources of infection with fungal diseases can be stems and leaves remaining on the site after the removal of dead bushes.
More often young actively growing shoots and leaves are sick. With air humidity below 60% and a temperature of 17-18 ° C, powdery mildew is almost not manifested. On the surface of leaves, stems, buds and thorns, a powdery mildew is formed of white, ash or grayish color. At first, the plaque is weak, occurs in the form of separate spots, but gradually it grows and forms a continuous mass on the surface of the affected area. As a result of the disease, tissues are destroyed and a number of physiological processes in roses are disturbed, leaves are twisted, young areas of shoots die prematurely.
Powdery mildew control measures on a rose: autumn pruning of affected shoots, collection and burning of fallen leaves. Digging the soil with a turnover of the reservoir - while the causative agents of the disease die from a lack of air in the soil. In autumn or early spring (before buds open), after pruning the affected shoots and harvesting the fallen leaves, they are sprayed with solutions of: 3% iron sulfate with 0.3% potassium sulfate or 3% copper sulfate.
During the growing season, excluding flowering time, regularly (after seven to ten days) is sprayed with other drugs that are approved for use on individual farms. For example, with a copper-soap solution: 200-300 g of liquid green soap (or 72% household soap) should be dissolved in 9 l of soft water (preferably rain); Dissolve 20-30 g of copper sulfate in 1 liter of water; stirring the soap solution quickly, pour a solution of copper sulfate into it with a small stream. The solution is ready to use.
For spraying use a 1% suspension of colloidal sulfur. Sulfur has a stimulating effect on the growth and development of roses, especially on alkaline soils. This is apparently due to its oxidation and subsequent increase in water-soluble nutrient reserves in the soil. Unilateral introduction of nitrogen enhances the development of the disease. Feeding with potash fertilizers increases the resistance of roses to powdery mildew. With a strong development of the disease, plants can be sprayed with soda ash (50 g per 10 liters of water).
In addition, in autumn and spring, soil around the rose bushes is sprinkled with wood ash (100-120 g per 1 m²) and lightly embedded in the surface layer. Once every seven days in the evening, five-day infusion of ash (200 g per 10 l of water) and mullein (1 kg per 10 l of water) is sprayed. Trace elements in ash and slurry are destroyed by the powdery mildew pathogen and contribute to the healing of roses. Thus, the biological method of control and foliar top dressing are carried out. Spraying is repeated until the signs of the disease disappear.
Black spotting (Marsonina)
This is a fungal disease, manifested in the form of black-brown spotting on the leaves of roses. Usually, signs of the disease become noticeable in the second half of summer. Dark brown radiant spots of different sizes form on leaves, petioles and stipules. With severe infection, the entire leaf darkens, the leaves dry and fall off. Mycelium and spores winter on shoots and leaves.
Measures to combat black spotting roses: collection and burning of diseased leaves, pruning and burning of diseased shoots, digging the soil with a turnover of the reservoir, autumn or early spring spraying of roses and soil before the buds open with one of the permitted preparations.
In spring, an orange dusty mass of spores appears on the stems near the blooming leaves and the root neck. In summer, small orange-yellow sporulation pads are visible on the underside of the leaves. The disease of roses with rust manifests itself more strongly in years with a warm and wet spring. As a result, the functions of the autonomic organs are impaired: transpiration increases, photosynthesis decreases, breathing is difficult, and metabolism is impaired. With the development of rust, plants are inhibited, leaves dry out, stems, shoots and flowers are deformed.
Rust control measures on a rose: pruning the affected shoots, collecting leaves and burning them, digging the soil, spraying roses before shelter for the winter with Bordeaux liquid or iron sulphate. During the growing season, they are treated with a copper-soap solution.
It appears in whitening or yellowing of leaves. The main reasons are the lack of iron, manganese, zinc, magnesium, boron and other elements in the soil. For example, with a lack of iron (usually on carbonate soils), the so-called calcareous form of chlorosis develops. At the same time, chlorotic coloration extends over almost the entire sheet, except for the veins. At first, the youngest are affected - the apical leaves. If the disease progresses, small veins become discolored. The leaf acquires an almost white or creamy-white color. Subsequently, the tissue dies, the leaf falls off.
With a lack of zinc, chlorosis spreads along the entire edge of the leaf and onto the tissue between the large lateral veins. Along the central and lateral veins, the leaf retains a green color. At the base of the veins, green sections of the leaf are wider.
With a lack of magnesium, the lower leaves turn yellow and die, the veins remain green, the edges of the leaves twist. Boron deficiency is manifested in the light color of young leaves, they become thickened and brittle. Young growing parts are ill, the ends of shoots (growth points) die off. Even with a slight excess of alkali, rose leaves begin to chlorinate, especially in the late fall and winter periods.
Rose Chlorosis Control Measures: establish the cause of the disease as a result of soil or plant analysis.Salts of the corresponding nutrients are introduced into the soil in prescribed doses.
Downy mildew, peronosporosis
One of the dangerous diseases of roses, especially rose hips. At the beginning of the disease, brown drying spots appear on the upper side of the leaves, on the lower side - a grayish, barely noticeable plaque of sporulation of the mushroom. Over time, brown spots become reddish-brown, gray gradually turn yellow, then turn brown. Affected tissues die, leaves fall off.
The disease develops especially severely in rainy and hot times.
Measures to combat rose peronosporosis: for the prevention of the disease with the onset of hot and rainy days, the bushes are sprayed with fungicides.
Preparation of spray solutions
For flower enthusiasts, copper-soap solution and lime-sulfur broth are not always successful. To prepare the drug efficiently, carefully observe the following procedure.
For a copper-soap solution, they take only warm, soft water, preferably rain. If it is not, add 5 g of soda ash or 2 g of dry mustard per 10 l of water to soften the water. For more than 5 hours, the solution should not be stored - it quickly deteriorates. The solution is prepared at the time of use in a wooden or enameled container.
In nine liters of hot (50-60 ° C) water, 300 g of liquid green soap is dissolved; for lack of it, 72% household soap is used. Then 30 g of copper sulfate are dissolved in 1 liter of hot water.
In a hot state, a solution of copper sulfate is poured into a soap jet with a thin stream. The contact area of the solutions is immediately shaken quickly or the liquid is mixed with a wooden stick. The solution turns blue. Before spraying, the drug is cooled to 20-25 ° C. If flakes fall in the liquid, the solution cannot be used.
Lime-sulfur broth is prepared as follows. For 17 liters of water, take 2 liters of ground sulfur and 1 liter of benign quicklime (or 1.5 liters of quicklime). Lime is quenched in a small amount of water, without bringing it to a boil. When the lime is heated, sulfur is added to it and, thoroughly mixing, add the rest of the water. The mixture is boiled over a fire for about 50 minutes from the moment of boiling, until it acquires a cherry-red color.
During boiling add water to the original volume. Stop topping up 15 minutes before the end of cooking. The finished broth is cooled, defended and filtered through a canvas in a glass, clay or enameled dish. The strength of the broth is determined by a hydrometer. Typically, its density is 1.152-1.162 g / cm3 (10-20 ° according to Bome).
To spray the plants take 180-220 g of the prepared broth (concentrate) per 10 l of water. Two to three days before the start of the treatment, a test spraying of one or two rose bushes is done. In the absence of burns on plants, the solution can be used for spraying. In case of burns on the bushes, lime should be added to the solution. Store the broth in a well-closed container in a dark, cool place.
To prepare 10 l of 1% Bordeaux liquid, you need to take 100 g of copper sulfate and 100 g of quicklime or 150 g of quicklime. In one glass, clay, enamelled or wooden dish, lime is extinguished or diluted (milk of lime is obtained), and copper sulfate is diluted in the other. Then slowly with a thin stream with rapid stirring, a solution of copper sulfate is poured into a solution of milk of lime. The resulting mixture is called Bordeaux liquid.
Determine the suitability for processing it as follows: cleaned from dirt and rust to shine, the knife or nail is lowered into the finished solution. If the iron object removed from the solution is covered with copper, then lime must be added to the bordeaux liquid until the plaque ceases to form. For the preparation of a 3% Bordeaux liquid, the amount of quicklime is accordingly increased to 300 g, of copper sulfate - also to 300 g.
Folk remedies for roses
From ancient times, people used original methods of controlling pests and diseases of roses in vegetable gardens. Used these methods and well-known rose growers. In the fight against various insect pests, N. I. Kichunov sprayed roses with tobacco broth (shag), aloe extract, kerosene, and others. V. Michurin used milk juice or an aqueous extract of his juice to protect roses from rust.
Remedies for rose diseases
From powdery mildew, roses are sprayed with infusion of mullein and ash. Diluted in 10 l of water 1 kg of fresh cow manure and 200 g of ash, stirring occasionally. Insist for seven days in a warm place, filter through cheesecloth, and the infusion is ready for use. Spraying infusion of ash and mullein is carried out with the appearance of the first signs of the disease. If the signs of powdery mildew do not disappear three to four days after spraying, the spraying is repeated. Further treatment with infusion is best alternated with treatment with fungicides.
With the development of rust, diseased bushes are often burned so that the disease does not spread throughout the site. Infusion of milk can save roses from rust. Michurin acted as follows: he broke off part of the stem of the milkweed and, with the end with a protruding drop of milky juice, rubbed the rusty spot of the plant. The operation was repeated two to three times a day.
If the disease appeared immediately on a large number of bushes, then do the following. 1.5 kg of milkweed stalks are taken per 10 l of warm water, after grinding them in a meat grinder or in another way, they insist in a warm place for one day. The concentrated aqueous extract of the juice is drained and used for spraying. The disease usually resolves after a second spray.
At the farm “Decorative cultures” of Kabardino-Balkaria, a case was noted when the dogrose, intended for budding, turned out to be infected with rust. The question was about the inevitable rejection of the entire stock. At the suggestion of I.P. Kovtunenko, the dog rose was half cut and sprayed with a 3% spindle oil solution. Some time after treatment, the stock was green and in the same year was oculized. The roses grown on it were healthy.
Remedies for pests of roses
400 g of shag or tobacco waste is boiled in 9 l of water for 30 minutes. The broth is insisted in a warm place for two days, filtered through two layers of gauze and canvas to avoid clogging of the nozzle of the sprayer. Dissolve 40 g of soap, preferably green, in 1 liter of water and mix with a decoction of shag. The composition is ready for spraying.
Pass 300 g of chopped onion or garlic and 400 g of fresh tomato leaves through a meat grinder, insist in 3 l of water for 5-6 hours. Filter the infusion. Bring water to its volume in a large bowl to 10 l, add 40 g of soap. The composition is ready for spraying.
Grind 200 g dry or 600 g fresh bitter pepper. Pour 2 liters of water into enameled dishes, pour the cooked pepper there, boil over low heat for 1 hour. The broth is infused for two days. Pieces of pepper in the broth are crushed, the broth is drained, the vegetable particles are squeezed. The solution is filtered, adjusted with water to 2 liters. Pour 1 liter of a decoction of pepper into 10 liters of water, add 40 g of diluted soap to the same. The composition is ready for spraying.
Pour 1 kg of dry leaf of yarrow or 1.5 kg of dry leaf and wormwood in 10 liters of warm water. Insist in a dark warm place for two days, filter. Before spraying, 40 g of diluted soap is added to the infusion.
200 g of freshly ground horse sorrel roots are introduced into 10 l of warm water, insisted for 2 hours in a warm place. Before spraying add 40 g of green soap. The composition is ready for processing plants.
Insist 500 g of dried Datura plants in 10 l of water for 12 hours. Before spraying, add 40 g of soap.
Yu. M. Kara against the spider mite uses:
- 2% solutions of a concentrated solution of tobacco, fern leaves, calendula seeds, onion scales;
- 3% - onion bulbs;
- 8% - yarrow and marigold leaves;
- 15% - wormwood;
- 20% - tops of potatoes and tradescantia leaves;
- 25% infusion of nightshade bitter.
According to him, on the third day after treatment, the death of the pest is 71% of the infusion of onion bulbs, 76.8% - of onion scales, 81.8% - of wormwood, 83.6% - of calendula, 84.6% - of potato tops, 87.5% from tradescantia, 88.5% from ferns, 96% from yarrow, 96.1% from marigolds, 98% from nightshade, 100% from tobacco infusion.
The used material: Sokolov N. - Roses.