What are the symptoms of root rot in spider plants? A detailed explanation of how it occurs

Root rot is a relatively common disease in spider plants. If you find that your spider plant's ability to absorb water and nutrients is gradually weakening, and the leaves wilt around midday but recover on their own at night, then it is very likely that your spider plant has root rot. Here, the editor introduces the symptoms and occurrence patterns of root rot in spider plants.

Spider plant

I. Symptoms

Root rot mainly harms spider plant seedlings, but plants at the mature stage can also develop the disease. In the early stage of the disease, only individual lateral roots and fibrous roots are infected, and it gradually spreads to the main root. After the main root is infected, the plant shows no symptoms at first. Later, as the degree of root rot intensifies, the ability to absorb water and nutrients gradually weakens. Because the above-ground part cannot get enough nutrients, only when the light is strong and evaporation is high around midday do the upper leaves of the plant wilt, but they can recover at night. When the disease is severe, the wilting can no longer recover even at night. At this point, the root bark turns brown and separates from the pith, and finally the whole plant dies.

II. Occurrence patterns

The pathogen overwinters in the soil and on diseased plant debris. The disease generally occurs from late March to early April, and enters its peak period in May. Its occurrence is closely related to climatic conditions. Low temperature, high humidity and insufficient light in the seedbed are the main environmental conditions that trigger this disease. Seedling beds with heavy, easily compacted soil and poor aeration impede root growth and development, making the disease more likely to occur. In addition, when roots are damaged by underground pests and nematodes, there are many wounds, which favors invasion by the pathogen. In such an environment, not only are herbaceous flowers propagated by sowing and cuttings susceptible, but woody flowers such as Chinese rose, cotton rose and Chinese hibiscus propagated by cuttings, division and layering are also prone to the disease.

Symptoms and control methods of root rot in spider plants

News from China Garden Network on November 19: [Symptoms] It mainly harms seedlings, but plants at the mature stage can also develop the disease. In the early stage of the disease, only individual lateral roots and fibrous roots are infected, and it gradually spreads to the main root. After the main root is infected, the plant shows no symptoms at first. Later, as the degree of root rot intensifies, the ability to absorb water and nutrients gradually weakens. Because the above-ground part cannot get enough nutrients, only when the light is strong and evaporation is high around midday do the upper leaves of the plant wilt, but they can recover at night. When the disease is severe, the wilting can no longer recover even at night. At this point, the root bark turns brown and separates from the pith, and finally the whole plant dies.

[Pathogen] This disease often has symptoms similar to root drowning, and is a fungal disease.

[Occurrence patterns] The pathogen overwinters in the soil and on diseased plant debris. The disease generally occurs from late March to early April, and enters its peak period in May. Its occurrence is closely related to climatic conditions. Low temperature, high humidity and insufficient light in the seedbed are the main environmental conditions that trigger this disease. Seedling beds with heavy, easily compacted soil and poor aeration impede root growth and development, making the disease more likely to occur. In addition, when roots are damaged by underground pests and nematodes, there are many wounds, which favors invasion by the pathogen. In such an environment, not only are herbaceous flowers propagated by sowing and cuttings susceptible, but woody flowers such as Chinese rose, cotton rose and Chinese hibiscus propagated by cuttings, division and layering are also prone to the disease.

[Control methods] 1. Disinfection of seeds and cuttings. Before sowing, seeds can be mixed with 0.3 % Tuzet at 0.3 % of seed weight or 0.1% triadimefon at 0.1% of seed weight, or soaked for 5 hours in a 2000-fold dilution of 80% 402 antibacterial emulsifiable concentrate; the base of cuttings can also be soaked for 1 hour in the same concentration of the solution before planting.

2. Disinfect the seedbed soil. Apply 1.5 grams of 50% carbendazim per square meter on the surface and turn it into the soil, or use 3 grams of 75% quintozene; both are effective, and can also control damping-off and seedling blight.

3 . Chemical control. When the disease occurs, spray or drench diseased plants with a 1000-fold dilution of 40% Genfuning; or drench the roots with a 1500-fold dilution of 8 0% 402 emulsifiable concentrate.

4. Timely control of underground pests and nematode damage.

Control methods for soft rot in red-flowered spider plants

Also known as bacterial soft rot and stem rot of red-flowered spider plants. It is distributed in all cultivation areas of red-flowered spider plants. It harms the rhizome area, causing plant death or failure of cuttings to survive.

Symptoms:It mainly harms the stem of the red-flowered spider plant where it contacts the soil, on which dark green water-soaked spots appear, causing soft rot; after drying and losing water, they shrivel, and the roots also rot.

Occurrence patterns:The pathogen is a bacterium, Erwinia carotovora. The pathogen survives with diseased plant debris and mostly invades through wounds. In summer, high temperature, excessive humidity and poor indoor air circulation make severe damage likely. When propagating by cuttingspropagation, the soil is heavy and has poor permeability. A damp, shady and unventilated environment can all cause the cuttings to develop disease and rot, so they cannot survive.

Control methods:

(1) Red-flowered spider plants like a warm, humid environment but cannot tolerate waterlogging. Therefore, choose a well-drained, loose, fertile loam for pot cultivation. Do not use heavy soil or soil treated with undecomposed organic fertilizer. The flower pot should be hung in a ventilated, cool place. Especially in the stuffy, hot days of the dog days, hang it in a ventilated place, but avoid direct sunlight.

（2）CuttingsWhen propagating, the cuttings can be inserted into washed river sand, kept ventilated, and sprinkled with water every day to maintain a certain humidity; they generally root in 10-15 days. The cuttings can also be soaked in a bottle of clean water, changing the water once a day, and potted after rooting. Do not insert the cuttings into heavy, poorly drained soil in a poorly ventilated environment, to prevent infection.

(3) For severe cases, discard the diseased plants together with the potting soil, disinfect the pot, replace it with new soil, and plant healthy seedlings.