Symptoms and occurrence regularity of root rot of Cymbidium

Root rot is a common disease of Cymbidium, if you find that your orchid's function of absorbing water and nutrients gradually weakens and the leaves of Cymbidium will wither around noon, but can recover at night, then there is a good chance that your orchid is suffering from root rot. The editor will introduce to you about the symptoms and occurrence regularity of the root rot of Cymbidium.

Hanging orchid

First, symptoms

Root rot is mainly harmful to Cymbidium seedlings, and it can also occur at the adult stage. At the initial stage of the disease, only individual branch roots and whisker roots were infected, and gradually extended to the main root. after the main root was infected, the early plant showed no symptoms, and then the function of absorbing water and nutrients gradually weakened with the aggravation of the degree of root rot. the aboveground part was in short supply of nutrients, the upper leaves of the plant wilted only when the light was strong and the evaporation was large around noon, but recovered at night. When the disease is serious, the wilting condition can not recover at night. At this time, the root bark turned brown and separated from the pith, and finally the whole plant died.

Second, occurrence regularity

Pathogens usually spend the winter in soil and on diseased bodies, usually from late March to early April, and enter the peak period in May, and their occurrence is closely related to climatic conditions. Low temperature and high humidity of seedling bed and lack of light are the main environmental conditions that cause the disease. The growth and development of root system is hindered due to the high viscosity, easy consolidation and poor ventilation of the soil, and the disease is also easy to occur. In addition, after the roots are harmed by underground pests and nematodes, there are many wounds, which is beneficial to the invasion of bacteria. In this environment, not only the herbaceous flowers of sowing and cutting are vulnerable, but also the woody flowers such as rose, hibiscus and mulberry are also easy to occur.

Symptoms and Control methods of Root Rot of Cymbidium

China Garden Network, November 19, news: [symptoms] to harm seedlings, the adult stage can also occur. At the initial stage of the disease, only individual branch roots and whisker roots were infected, and gradually extended to the main root. after the main root was infected, the early plant showed no symptoms, and then the function of absorbing water and nutrients gradually weakened with the aggravation of the degree of root rot. the aboveground part was in short supply of nutrients, the upper leaves of the plant wilted only when the light was strong and the evaporation was large around noon, but recovered at night. When the disease is serious, the wilting condition can not recover at night. At this time, the root bark turned brown and separated from the pith, and finally the whole plant died.

[pathogen] the disease is often similar to retting root symptoms and belongs to fungal disease.

[occurrence regularity] the pathogen spent the winter in the soil and on the residual body, usually from late March to early April, and entered the peak period in May, and its occurrence was closely related to the climatic conditions. Low temperature and high humidity of seedling bed and lack of light are the main environmental conditions that cause the disease. The growth and development of root system is hindered due to the high viscosity, easy consolidation and poor ventilation of the soil, and the disease is also easy to occur. In addition, after the roots are harmed by underground pests and nematodes, there are many wounds, which is beneficial to the invasion of bacteria. In this environment, not only the herbaceous flowers of sowing and cutting are vulnerable, but also the woody flowers such as rose, hibiscus and mulberry are also easy to occur.

[control methods] 1. Disinfect seeds and cuttings. Before sowing, the seeds can be mixed with 0.3% of seed weight or 0.1% of seed weight, or soaked in 2000 times of 80% antibacterial agent EC for 5 hours; the base of cuttings can also be soaked in the same concentration for 1 hour before cutting.

2. Seedbed soil disinfection, 1.5 grams per square meter of carbendazim scattered on the surface into the soil, or 75% pentachloronitrobenzene 3 grams have a good effect, and can also treat quenching disease, blight disease.

3. Chemical control. When the disease occurs, the diseased plant can be sprayed or irrigated with 1000 times of 40% Gen Fu Ning, or 80% EC of 1500 times can be used for root irrigation.

4. Control the harm of underground pests and nematodes in time.

Control methods of soft rot of Carthamus tinctorius

Also known as safflower Cymbidium bacterial soft rot, stem rot. Carthamus tinctorius is distributed in all the cultivation areas. Damage to its rhizome, resulting in plant death, or cuttings can not survive.

Symptoms: it mainly harms the stem of Carthamus tinctorius in contact with soil, showing dark green water stains on it, causing soft rot, wrinkling after drying and water loss, and root rot.

Disease regularity: the pathogen is bacteria, Erwin's soft rot bacillus. The bacteria survived with the remains of the disease and mostly invaded from the wound. The environment such as high temperature, excessive humidity and poor indoor air circulation in summer are easy to cause serious harm. When cutting propagation, the soil is sticky and the permeability is poor. The environment is damp and unventilated, which can cause cuttings to rot and cannot survive.

Prevention and control methods:

(1) Carthamus tinctorius likes warm and humid environment, but it is not resistant to waterlogging. Therefore, it is necessary to select well-drained, loose and fertile loam for potted plants. Do not use sticky soil with unmatured organic fertilizer. Flowerpots should be hung in ventilated and cool places, especially in muggy weather. Hang them in a ventilated place, but avoid direct sunlight.

(2) when cutting and propagating, the cuttings can be cut in the washed river sand, keep ventilated, sprinkle with water every day to maintain a certain humidity, generally take root in 10-15 days, or soak the cuttings in a water bottle, change the water once a day, and install the basin after taking root. Do not insert cuttings into sticky, poorly drained soil and poorly ventilated environment to prevent disease.

(3) if the disease is serious, discard the diseased plant together with the basin soil, disinfect the basin and replace it with new soil, and plant healthy seedlings.