Types and control methods of rose diseases and insect pests in Xiushan County

Types and control methods of rose diseases and insect pests in Xiushan County

Roses, native to China, belong to the family Rosaceae, Rosaceae, and roseaceae. In Europe, roses, roses, and moon seasons are called roses. The rose is the national flower of the United Kingdom and the city flower of Jilin, Shenyang and other cities in China. "Rose" in the popular sense has become a common name for a variety of rose plants. As an important flowering plant, the rose has always been loved by people for its large and gorgeous flowers, diverse flowers, strong color and delicious taste, and beautiful meaning. In addition, it has many practical medicinal and edible values, and its flowers and fruits can be used in a variety of foods and to refine essential rose oil. The flowers and roots of the first bloom of the rose can be medicated, and have the effects of rational qi, blood invigorating, and astringent. Therefore, roses have the reputation of "golden roses".

In recent years, Qingxichang Town, Xikou Town, Pingkai Street and other places in Xiushan County, Chongqing City, in the form of rose gardens, agricultural companies, farmhouses, etc., large-scale planting of roses has reached more than 100 hm2, and it has shown a trend of increasing year by year. Because roses have both ornamental and economic value, their development momentum is good. Xiushan County is located in the hinterland of Wuling Mountain, belongs to the subtropical humid climate zone, high temperature and rain, little sunshine, and great humidity in the field, which is conducive to the occurrence, epidemic and spread of rose diseases and insect pests. According to the investigation of Xiushan County Plant Protection plant inspection station in recent years, xiushan county rose disease mainly includes more than ten kinds of black spot disease, powdery mildew, blight and other diseases, and the main insect pests are aphids, red spiders, tianniu and so on. In general, the production of roses in Xiushan County is more harmful than insect pests, and pests and diseases cause greater harm to rose production.

1 Rose disease

1.1 Rose black spot disease

1.1.1 Identification of rose black spot disease Rose black spot disease is a worldwide disease that occurs very commonly and is one of the most harmful diseases to roses. The pathogens of Rosa nigra disease belong to the subphylum Hemiphalus, the order Black Discospores, and the genus Actinomycetes. Foliage, flowers, and new shoots occur. At the beginning of the leaf, there are dark spots of varying sizes, and there are radial brown hyphal threads and small black spots (conidia discs) under the stratum corneum of the lesions. It expands and appears yellowish-brown or dark purple, and finally turns gray-brown, and when it is severe, the new shoots die and the entire lower leaves of the plant are completely shed.

1.1.2 Prevention and control methods of rose black spot disease The main prevention and control methods include: (1) winter garden clearance. Remove dead branches and spray 29% stone sulfur water agent for protection. (2) Strengthen cultivation management. One is to keep the field ventilated and transparent, and control the humidity in the field; the second is to apply more phosphorus and potassium fertilizer and less nitrogen fertilizer to improve the plant's disease resistance; the third is to spray as little water as possible during the onset period, or only spray water in the morning when the weather is clear, to avoid wetting the foliage for a long time. (3) If the diseased leaves and branches are found, they should be completely pruned and burned centrally to reduce the source of infection. At the beginning of the disease, 50% carbendazim wettable powder, or 70% manganese zinc wettable powder, or 80% methylthiophilin wettable powder 600 to 800 times liquid can be sprayed, according to the development of the disease, the interval is 7 to 10 days, sprayed 2 to 3 times, pay attention to the rotation of the agent.

1.2 Powdery mildew rose

1.2.1 Identification of powdery mildew Rose powdery mildew is a common disease in Xiushan, and its pathogen belongs to the subphylum of subphylum, powdery mildew, and single-bundled trepidation. The disease mainly harms the young leaves and flowers of the young shoots of roses. The appearance of white powder at the infected site is a clear symptom of this disease. A faded green macula is produced on the initial leaves, and later a white spot appears on the underside of the leaf, which gradually expands into an irregular shape. In severe cases, the white spots are connected to each other in pieces. The young shoots of the plant are curled and crumpled. The surface of the buds is covered with white powder, and the flowers are deformed. The white powder layer on the petiole and skin spines is thick and difficult to peel off, causing the plant to fall leaves, and the buds are stiff and cannot open normally. The onset period is from May to September of each year, and the symptoms are more obvious, so it is easier to identify and prevent.

1.2.2 Prevention and control methods of powdery mildew The main prevention and control methods include: (1) remove diseased branches and leaves in autumn and winter, prune diseased buds, diseased branches and diseased leaves in early spring, and bury or burn them in a concentrated manner. Improve cultivation conditions, increase ventilation and light transmission, apply less nitrogen fertilizer, and apply more phosphorus and potassium fertilizer. (2) At the beginning of the disease, 12% rusty spirit wettable powder, or 60% pyrazol manganese zinc wettable powder, or 56% ether bacteria pyrimidine suspension agent, or 25% triazolone wettable powder 800 to 1 000 times liquid spray prevention and treatment, according to the development of the disease, interval 7 to 10 days, spray 2 to 3 times.

1.3 Rose blight

1.3.1 Identification of rose blight The main harm to the branches of the plant is the pathogen of the subphylum hemiknophyllum, the spherical spore, and the genus Shieldshell. Initially small red spots, later enlarged and darkened, the brown and purple edges around the spots contrasted significantly with the green of the stem, the conidia of the pathogen appear when the center of the plaque becomes brown, with the enlargement of the conidia, the longitudinal cracks appear in the epidermis of the stem, and the later lesions are depressed and longitudinally cracked, and black spots appear in the center of the disease, and black spore piles emerge when wet. When the disease is severe, the branches and leaves above the diseased part shrink and die.

1.3.2 Prevention and control methods of rose blight The main prevention and control methods include: (1) Do a good job of clearing the garden in autumn and winter, and completely cut off the diseased and dead branches and burn them in a concentrated manner. During the dormant period, 29% stone sulfur compound was sprayed with water agent protection. (2) Strengthen cultivation management, apply sufficient base fertilizer, and enhance plant growth. (3) Choose to prune on a sunny day. The cut is first disinfected with 10% copper sulfate, and then a callus antiseptic film is applied to protect the growth of wound healing tissue and prevent the infestation of decaying bacteria. After pruning and grafting, management should keep up to promote early healing of wounds. (4) At the beginning of the disease, 50% carbendazim wettable powder, or 70% bacillus qing wettable powder, or 80% methylthiophilim wettable powder 600 to 800 times liquid.

1.4 Rose phyllosa

1.4.1 Identification of rose phylloxera Caused by nematodes, the pathogen is bundle nematodes. Symptoms are white tumors in the root knots, with a long residual period and greater harm. The larvae and males are linear, the females are pear-shaped, and when they are expanded, they break through the root cortex and expose them, which is a white nodule seen in the roots. The larvae are white and elastic and later harden. The surface of the tumor is rough. Brown or black-brown, in severe cases, nodules can grow out of the ground. Roses with long rhizomas grow poorly, the foliage is yellow, the number of roots is reduced, and the nodules grow exponentially.

1.4.2 Control methods of rose phylloxeracosis The main control methods include: (1) soaking the roots of plants with 72% agricultural streptomycin soluble powder 500-600 times liquid for 10-15 minutes before planting. (2) When grafting, the knife will be sterilized with high temperature or sake to avoid nematodes from invading the wound. (3) Coating the affected area with methanol, glacial acetic acid, iodine tablets (50:25:10) mixed liquid; or coating the affected area with sodium dinitro-o-cresol and wood alcohol (20:80) mixture, can make the tumor disappear.

1.5 Rose rust

1.5.1 Rose rust identification Rust damages rose buds, leaves, young branches, petioles, flower trays, peduncles and other parts of the rose. Occurs mainly on buds and leaves. Rose rust pathogens belong to the subphylum Basidiomycetes, Rust order, and polycellular rust bacteria. Rust spores are piled on the back of the leaf into an orange-red powdery substance, surrounded by lateral filaments, naked. Rusty spores are strung together, summer spores are stacked, surrounded by stick-like side filaments, and winter spores are black and loosely exposed. In the spring budding stage, the base of the diseased bud is enlarged, and a large amount of orange-red powder grows in the 1 to 3 layers of scales; some curves are deformed, and they die after 15 to 20 days. After the young leaves are damaged, they first grow on the front of the leaf, with small yellow dot-like spores, and then form orange-red spore piles on the back of the leaf. In autumn, after the axillary buds are infected by pathogens, they die after overwintering.

1.5.2 Rose rust control methods The main prevention and control methods include: (1) timely removal of diseased buds, inspection in late March to April, found that the diseased buds should be immediately removed and destroyed. The general disease bud rate is less than 0.5%, and the spore spread can be prevented after removal. (2) Before the peak of the disease in early April or late August, spray 1 to 2 times to control the development of the disease. The agent is the same as that of powdery mildew mentioned above.

1.6 Rose gray mold

1.6.1 Identification of Rose Gray Mold One of the main diseases of Xiushan, the disease is caused by fungi, the pathogen is Botrytiscinerea, and the trait is Sclerotinia fuckliana. Pathogens overwinter on the remains of the disease and spread by air currents in the spring of the second year when conditions are right, invading from wounds or weakened organs. Xiushan County is generally susceptible to illness during the rainy season and flowering period in June and July. Rose gray mold is one of the most harmful diseases of roses, and humid environments are more likely to occur. When the disease occurs at the leaf margin and tip, it initially appears as water-stained pale brown spots, smooth and slightly sunken, and later enlarged and decayed. The buds become sick, the spots are gray and black, and the buds turn brown and die. When the petals are damaged, some of the petals turn brown and wrinkle and rot. Gray mold also infects the branches after the folding flower, in a warm and humid environment, the gray mold layer can completely cover the infected area, and the gray mold layer is a prominent feature to identify the disease.

1.6.2 Rose gray mold control methods The main control methods include: (1) timely removal of the diseased part, reduce the source of infection, and timely pruning of withered roses. (2) When cultivating in greenhouses, the greenhouse should be properly ventilated, so as not to cause excessive temperature difference between day and night and too high humidity. When potting, there should be appropriate gaps between each rose pot. When watering, pour from the edge of the pot, do not let the leaves and flowers retain water. (3) Chemical control. At the beginning of the disease, 45% Trichoderma suspension, or 50% isobacterium urea Fu wettable powder, or 20% pyrimidine wettable powder 800 to 1 000 times liquid, or 80% humus water dispersible granules, or 687.5 g/L fluorobacteria and downy mildew suspension 1 000 times liquid, 7 to 10 d spray once, spray 2 to 3 times continuously, pay attention to rotation and mixed drugs, in order to prevent drug resistance.

1.7 Rose anthrax

1.7.1 Identification of rose anthrax Rose anthrax is caused by fungi, and the pathogens are subphylum hemiknomycetes, columnar septum, and gelospore anthrax. The disease occurs under high temperature and humid conditions, and the harm is serious. Leaf lesions, symptoms are generally manifested in the leaf margin, semi-circular spots, dark brown edges, the middle of the brown to light brown; later in the occurrence, the middle of the spots become gray, often shedding. The spots are uniformly black with irregular radial edges. In a humid environment, the spots have small black dots, the conidia of pathogenic bacteria.

1.7.2 Prevention and control methods of rose anthrax The main control methods include: (1) combined with pruning in winter to remove diseased branches and leaves, remove fallen leaves, and concentrate on destruction. (2) Strengthen fertilizer and water management, improve plant resistance, drain water in time after rain, maintain appropriate temperature and humidity, and reduce germ infestation. (3) At the beginning of the disease, 50% phenyl ether and amide wettable powder 1 000 times liquid, or 80% methyl thiophanol wettable powder 800 times liquid spray prevention and treatment, according to the disease of 1 to 2 times.

1.8 Rose verticillium wilt

1.8.1 Identification of rose verticillium wilt Rose verticillium wilt is a common disease that is more serious, especially the greenhouse rose is prone to disease. Its pathogen belongs to the semi-known fungus, and the symptoms of infected plants are manifested in the stem, and there is a fading phenomenon between the leaf veins of the apical leaves, and then gradually become brown and wither. The lower leaves are yellowed. Sometimes brown to black spots appear on the xylem at the base of the diseased stem. Severe cases can cause the entire plant to die.

1.8.2 Rose Verticillium Wilt Control Methods The main control methods include: (1) strengthen cultivation management, rational fertilization and irrigation, and improve plant resistance. Reasonable dense planting, adjust ventilation and light transmission, timely drainage after rain, maintain appropriate temperature and humidity, clean up disease residues, and reduce the source of disease. (2) Disease-resistant rootstock grafting is selected. (3) Do not plant with tomatoes, potatoes, chrysanthemums, sunflowers and other crops. Avoid infection of germs. (4) Immediately after the discovery of the central diseased plant, remove the diseased plant and bury it deeply, and scatter lime to disinfect the disease socket. In severe cases, 70% methylthiopyrifolim bis-wettable powder, or 50% carbendazim wettable powder 500 to 600 times liquid, 90% methyl liqualin original powder wettable powder 800 to 1 000 times liquid, about 0.5 kg per plant.

1.9 Rose virus disease

1.9.1 Rose virus disease identification Rose virus disease mainly harms leaves, and is one of the serious diseases of roses. Pathogens include Rose Mosaic Virus, Arabidopsis Mosaic Virus, Strawberry Latent RingEdosis Virus, Tobacco Stripe Virus, Plum Necrotic Ringed Spot Virus, etc. Viral diseases are mainly manifested as fading green along the leaf veins, producing irregular pale yellow to orange patches on the leaves, some of which are ring-shaped or oak-like patterns, and some of which are small horn spots, linear leaves, local deformities or yellow veins or yellow flowers. Leaf yellowing, creases, and deformities are typical features of the disease.

1.9.2 Prevention and control methods of rose virus disease The main prevention and control methods include: (1) breeding and planting disease-resistant varieties according to local conditions. (2) Stem and plant treatment. Promote the use of detoxified seedlings, pay attention to the use of disease-free scion and rootstock as propagation material. (3) Pharmaceutical prevention and control. At the beginning of the disease, 5.9% capryria morpholine guanidine aqueous agent or 68% ningnan pyropeptide aqueous agent 800 to 1 000 times the liquid were uniformly sprayed and controlled, and the drug was administered 1 to 2 times according to the condition.

1.10 Rose brown spot disease

1.10.1 Identification of rose brown spot disease Rose brown spot disease is one of the common diseases that harm roses, and rose leaves, young branches and flower stems can be affected. Pathogens belong to the subphylum ascomycete fungus. The spots on the leaves are initially purple-brown to brownish dots, and later expand into larger round spots, black or dark brown, with ciliated margins, but the upper edges of individual species can also be neatly smooth. The spots are often surrounded by a yellow halo. Young shoots and peduncles are infested, producing purple to black striped spots that are slightly sunken. When the disease is severe, the lower and middle parts of the whole plant are all shed, leaving only the top few new leaves.

1.10.2 Prevention and control methods of rose brown spot disease The main prevention and control methods include: (1) complete removal of dead branches and leaves in winter to reduce the source of disease. (2) Chemical control. At the beginning of the disease, 50% carbendazim wettable powder, 80% methylthiopramine wettable powder, or 70% daisen manganese zinc wettable powder 600 to 800 times liquid spray prevention and control, spray 1 time every 7 to 10 days, spray 2 to 3 times continuously. Pay attention to the alternating use of the agent. Manganese zinc is harmful in some rose varieties, and the concentration of use is reduced to about 1 000 to 1 200 times.

1.11 Rose coal pollution disease

1.11.1 Identification of rose coal pollution disease Rose coal pollution disease is affected by other diseases and insects, and is caused by a variety of pathogenic bacteria. Coal pollution disease affects plant photosynthesis, makes plant growth poor, leads to weak growth and less flowering of rose plants, and seriously affects rose quality and ornamentality. At the beginning of the disease, small brown coal powder spots appear on the leaves, and the spots gradually expand and form large patches, covering the leaf surface and young shoots. Some mold layers are thick, black flake-like and upturned, easy to peel off.

1.11.2 Rose coal pollution control methods The main control methods include: (1) In the flower and tree growing season, especially in the spring, insecticides can be sprayed to control aphids, mesozoles, etc., and commonly used agents are imidacloprid, thiamethoxazine, thiazide and so on. (2) Appropriately reduce the planting density to facilitate ventilation and light transmission; timely pruning of plants. (3) At the beginning of the disease, 70% daisen manganese zinc wettable powder, or 80% methyl thiophanate wettable powder, or 80% daisen zinc wettable powder and other agents were selected for 600 to 800 times spray prevention and control.

1.12 Rose downy mildew

1.12.1 Identification of rose downy mildew Downy mildew rose is one of the main diseases that harm the growth of roses, and the leaves, new shoots and flowers of roses can be diseased. The pathogen is Diplocarpon rosac. Irregularly shaped pale green patches appear on the leaves at the beginning of the disease, which later enlarge to yellowish brown and dark purple, and finally grayish brown. The edges are darker and gradually expand to spread to healthy tissues without obvious boundaries. In wet weather, a sparse layer of gray-white downy mold can be seen on the back of the diseased leaf. Some of the spots are purple-red and gray-white in the center, as if they were burned by fertilizers and pesticides. When the new shoots and petals are infected, the spots are similar to those on the diseased leaves, but the spots on the tips are slightly sunken. In severe cases, the leaves atrophy and fall off, and the new shoots rot and die.

1.12.2 Rose downy mildew control methods The main control methods include: (1) remove diseased leaves, diseased stems and diseased flowers to reduce the source of infection. (2) Appropriately reduce the planting density and enhance the ventilation and light transmittance of the field, which can reduce the incidence of disease. (3) At the beginning of the disease, 68.6% propensin valerian suspension, or 72% frost urea manganese zinc wettable powder, or 70% Bacillus Qing wettable powder, or 70% Daisen manganese zinc wettable powder 600 to 800 times liquid, or 80% enoyl morpholine water dispersible granules 1 000 times liquid spray control, 5 to 7 days spray again, 2 to 3 times continuously. Pay attention to the alternating use of various agents, and the spray should be even and thoughtful.

2 Rose insect infestation

According to the survey, the main insect pests of roses in Xiushan County are aphids, red spiders, and celestial bulls.

2.1 Aphids

2.1.1 Hazard symptoms Aphids on roses occur several generations a year, and occur more seriously between May and September, with adults and nymphs as the new shoots, young leaves, peduncules, and buds of roses, sucking the host juice, making the heart leaf wrinkles unable to unfold, endangering the buds affecting the normal opening of the flowers, and causing the petals to leave spots, seriously affecting plant growth. Under open-field cultivation conditions, aphids occur in early spring and early summer. When cultivating in facilities, timely control generally does not occur seriously. The "honeydew" secreted by aphids is easy to induce coal pollution diseases, viral diseases and so on.

2.1.2 Control methods The control of aphids is relatively simple, using 30% pyrazole and thiamethoxazine suspension, or 50% pyrithodone wettable powder, or 80% alkenin pyrithodone water dispersible granules, or 70% imidacloprid wettable powder 800 to 1 000 times liquid, uniform spray control, the prevention effect is generally above 90%.

2.2 Red Spider

2.2.1 Hazard symptoms Red spiders occur in spring and autumn, and red spiders absorb chlorophyll in the leaves, reducing the efficiency of rose photosynthesis, and multiplying rapidly, which can quickly cause leaf damage and plant development to stop.

2.2.2 Control methods for the control of red spiders, optionally 20% acetazole suspension 1 500 times liquid, or 20% pyridoxine wettable powder 1 500 times liquid, or 73% alkyne mite special emulsion 2 000 times liquid, or 20% egg mite net wettable powder 2 500 times liquid spray control.

2.3 Celestial Bull

2.3.1 Symptoms of harm There are many types of Tianniu, of which the largest number and most common are in addition to the Xingtianniu and Sangtianniu, there are also bare-shouldered Tianniu, Peach-necked Tianniu, White-ribten Tianniu, Red-edged Tianniu and so on. It is a typical feature of the borer pest that causes drilling holes in the stems. When the tianniu is seriously harmful, it can cause the death of the whole plant.

2.3.2 Control methods Control time should seize the favorable opportunity after the adult insects feather from mid-May to early June, before the larvae hatch, to prevent the larvae from entering the main trunk of the moth, other periods should be timely prevention and control, reduce the harm of insect pests. The first is manual prevention and control. Adult celestial bulls have weaker flight power and can be artificially hunted during the peak of feathering. Whitening the base of the autonomous trunk with lime water around the trunk prevents adults from laying eggs. At the base of the main trunk, after the egg laying groove with yellow foamy fluid glue is found, the egg groove can be smashed with a wooden hammer to kill the eggs and hatching larvae in it. Adult mulberry cattle have a suspended death, and are easy to kill artificially during the peak of feathering. During the larval infestation period, a metal wire is inserted through the fresh fecal hole to stab the larvae in the moth tunnel. The second is chemical control. It can be injected into the borer hole with dichlorvos, oxylea fruit, chlorpyrifos and other agents, and sealed the hole with mud or cotton balls, which can poison the larvae in the moth tunnel. The third is light booby-trapping. Using the phototropism of Tianniu, insecticidal lamps or solar insecticidal lamps are installed in the field for booby-trapping, and the controllable area of each lamp is generally 2.67~3.33 hm2. Yoshiyama Huayao