Common diseases of cyclamen soft rot

Cyclamen

Cyclamen with red flowers and green leaves is a kind of perennial herbaceous plant. The flowers come from the top of the tuber, showing their personality and being favored by young girls. However, such flowers and plants are easy to suffer from soft rot in the case of improper maintenance. The sick cyclamen seriously affects the ornamental value and economic value. However, what is called cyclamen soft rot is described below.

I. pathogen

Erwinia is a bacterium.

Second, symptoms

The pathogen of cyclamen soft rot is mainly spread by foliar watering and fertilization, which mainly harms the leaves. Water-immersed spots appear after the leaves are infected, and the disease spots are white or yellowish at first and dark brown gradually. On a sunny day, the leaves turn brown and yellow and gradually dry up, the internal tissues of the susceptible parts are broken down into water by bacteria, the leaves lose their support and droop, and after the leaf base or heart leaves are infected, the petioles and pedicels soften and quickly wilt and lodge in cloudy days, and gradually spread to the bulb. Under wet conditions, the external tissue of the disease site expands, the rupture and decay has a bad smell, and the internal tissue is dark brown, which often leads to the death of the whole plant within a few days.

Third, occurrence regularity

The pathogenic bacteria overwintered and survived in the soil, and the bacteria were transmitted by contact with running water, insects and diseased leaves, invaded from the wound, and the disease could occur a few days after invasion. Re-infection can be carried out many times in the growing season, which usually occurs from June to September. High temperature and rainy, plant wound is easy to occur, wet disease is serious. However, if the humidity is too high in winter, if the humidity is more than 20 ℃ for a long time, the plant will be injured while working, and the disease will often occur.

Cyclamen

IV. Prevention and control methods

1. To prevent the occurrence of soft rot, we should start from planting seedlings. The first is to disinfect the flower pots with 0.5% rain 1% formalin solution, or to expose them to the sun on a sunny day with a daily temperature of more than 30 ℃ for two weeks, using ultraviolet rays in the sun to kill bacteria, or to stir-fry the soil to kill bacteria in the soil. The bulbs can be disinfected with formalin solution at 1:80 or soaked with potassium permanganate.

two。 Strengthen cultivation management. Water properly to prevent the basin soil from getting too wet. If watering is really needed and some plants are sick, pull out the diseased plant two days before watering, dig out the soil from the root of the diseased plant, sprinkle some quicklime or plant ash, loosen the soil, and then sprinkle some quicklime on the soil surface, or spray fungicides. Secondly, fully mature fertilizers should be applied, ventilation and cooling should be paid attention to when it is hot and humid, and insect pests and other pests should be controlled in time to prevent insect pests from causing wounds. Finally, do not hurt the plants when planting and transplanting. Diseased leaves, diseased flowers and diseased plants should be cut off and destroyed in time to reduce the source of infection and avoid mutual infection.

3. At the initial stage of the disease, streptomycin or oxytetracycline can be sprayed or irrigated with roots, or 72% of agricultural streptomycin sulfate soluble powder 3000 times can be sprayed, once every 10 days, for 2-3 consecutive times.

4. When the disease is more serious and there is partial decay at the base of the root, the diseased part can be peeled off and the remaining rhizome can be soaked in disinfectant solution for 3 hours. Now it can be planted in plain sand, new roots can grow soon, new buds can be sent out, and then replanted with sterilized culture soil.

Editor's tip: do not confuse cyclamen's soft rot with cyclamen stem rot, because most of the stem rot is caused by too much watering, which is very similar to the symptoms of soft rot, but the cause is completely different, so the prevention and treatment methods are also different!

Control cyclamen (Cyclamen persicum Mill.), alias turnip, rabbit ear flower, rabbit flower, a crown, bonspark, turn petal lotus, is Primulaceae, cyclamen perennial herbs, leaves from the top of the tuber, heart-shaped, egg-shaped or kidney-shaped, leaf serrulate, leaf surface green, with white or gray halo spots, leaf back green or dark red, petiole longer, reddish brown. Cyclamen is a widely cultivated flower, which is suitable for indoor flowerpots and greenhouse in winter. Some cultivated species of cyclamen have strong aroma, while others have light or no aroma.

Prevention and control of cyclamen common diseases and insect pests 1. Fusarium oxysporum disease cyclamen is very easy to get sick and should be planted in a clean and well-drained place. The main disease is Fusarium oxysporum, which often lurks on the seedlings until it begins to occur after the seedlings are transferred. In the process of transportation, attention must be paid to the management of temperature and humidity, strict disinfection, and disinfection of soil and flowerpots. The yellowed seedlings were thrown away and the seedlings were prevented by methyl topiramate or chlorothalonil 5 weeks after transplantation. Second, after the seedlings of wilt disease are moved, the stems and leaves are stunted, black fungi appear on the edge of the leaves, and light red lesions appear in the vascular bundle system of petioles and corms; there are large patches of light orange spores on the organs of the residual plants, and the disease will spread rapidly; take out the diseased plants, apply methyl topiramate or chlorothalonil to control. Third, the symptom of soft root disease is that the plant wilts suddenly, then lodging, and the bulb is small; the main reason is that the bulb is buried too deep, the temperature is too high, the humidity is too high, and so on; it is necessary to avoid watering by spraying in the high temperature season. Fourth, Botrytis cinerea flowers and leaves appear soft rot, flowers appear spots and gray mold. Reduce the temperature, increase ventilation, increase the distance between seedlings, pay attention to the night temperature is not too low, fungal fungicides can be used to control. Fifth, the symptoms of Fusarium wilt disease are yellow or brown rings on the petiole, flowers deformed, plants stop growing, the disease is mostly transmitted by thrips, the disease can be controlled by insects. Cyclamen spider it will cause leaves deformation, curl, part of the flower discoloration, flower stem distortion deformation. As well as other pest control. Prevention and control of common diseases and insect pests in cyclamen

The common diseases of cyclamen are bacterial soft rot, gray mold, anthracnose, leaf spot and root nematode disease.

Bacterial soft rot: caused by bacteria of the genus Eucella. Most of them occur in petiole and corm. At the beginning of the petiole disease spot is a small light brown spot, water-like soft rot. After expansion, the diseased tissue was soft rotted, expanded, ruptured, detached from the epidermis and smelly. After corm infection, the tissue became yellowish brown, soft rot and paste. It is easy to get sick in the growing season and early spring. After discovery, the diseased and residual tissue should be cleaned in time to reduce the source of infection, strengthen ventilation and control watering, spray with 200ppm-1000ppm streptomycin, oxytetracycline or penicillin solution at the initial stage of the disease, or smear the diseased plant, and then sprinkle the diseased plant basin with the same amount of Bordeaux solution or 0.40 stone sulfur mixture.

Botrytis cinerea: caused by half-known fungi of the genus Grapevine. Most of them occur on leaves and petioles. The disease spot is dark green to yellow-white spot at first. Water stains, enlarged plaques are irregular, sunken, soft rot, dark color. Soft grayish-brown mildew appeared on the disease spot under wet conditions, that is, the meristematic pile of pathogens, and the late pedicel and abortive flowers were also covered with gray mildew spots. Repeated infection can be done in the greenhouse. But it is mainly from February to April, July to August. High temperature, humidity and poor ventilation are beneficial to the occurrence of the disease. After discovering, clean up the diseased plant in time, adjust the temperature, humidity and ventilation condition; spray I% equivalent Bordeaux solution, 2000 times of polyantimycin or 1000 times _ 1500 times of topiramate at the initial stage of the disease.

Anthrax: caused by half-known fungi of the genus Alternaria. It occurs on leaves and petioles. Most of the disease spots on the leaves occur on the back of the leaves. The disease spot is brown at first, and the edge is not obvious. The disease spot expanded outward in the shape of a wheel, nearly to irregular shape, black inside and yellow on the edge, and gray-black particles appeared on the disease spot in the later stage. Under wet conditions, the gray-white colloid was squeezed out, that is, the meristem disk and meristem of the pathogen. The diseased leaves do not fall off after they have dried up. Most of them occur from May to July. High temperature and humidity, suffering from bacterial soft rot, which is beneficial to the occurrence of diseases under the conditions of aphids and red spiders. Diseased leaves and insects were removed in time after discovery, and 60% anthrax Fumei r -} solution or 70% topiramine 1500 times solution were sprayed at the initial stage of the disease.

Leaf spot disease: caused by pathogens, the damaged leaves appear black spots and expand, and then become light brown and withered. After discovery, diseased leaves should be removed as soon as possible, ventilation should be strengthened or equal volume Bordeaux solution should be sprayed.

Root nematode disease: caused by pathogen infection caused by nematodes. The root is uplifted and nodular, the plant growth is weak, and the leaves wither. When it is found, 2000-4000 times of mercury water can be used for soil disinfection. In order to prevent the occurrence of nematodes, potted soil must be disinfected and killed in advance.