Why your sukuma wiki has black circular spots

During cold and rainy seasons, leafy vegetables are susceptible to diseases normally caused by fungi, bacteria, or viruses. If you grow greens or planning to grow them, here are the common diseases you need to know of, their causes, prevention, control, and treatment.

Downy mildew

This is the most common fungal disease affecting vegetables. Affected leaves show white mold and faint yellow spots on the dorsal and ventral sides of the leaves respectively. The fungus thrives in cold and wet conditions. The disease can be controlled by uprooting the infected crop and burning it, and you can treat it by using the recommended fungicides.

.

Keep Reading

Alternaria leaf spot

This is common, especially in Sukuma wiki. The affected leaves have black or brown circular spots. With time, the spots enlarge and concentric rings appear on them. You can prevent the disease by planting disease-free transplants. Uproot and bury or burn the infected crop. You can also spray your crops with a suitable fungicide immediately after you see the symptoms.

White spot is a leafy vegetable disease that causes leaves to have brown or gray spots, the leaves, later on, turn yellow and fall off within a few days. The fungus can survive on seeds, so you can prevent it by planting certified seeds. You can also prevent harmful microorganisms by avoiding cool and damp conditions in your garden. The best way to control white spots is to eradicate the infected crop. The disease spreads fast, so you should remove the sick crop immediately after seeing the symptoms. The fungus can be killed by suitable fungicides and copper products.

Anthracnose

It affects leaves and stems of vegetables like turnips and causes small, gray, or black spots on these parts. The harmful microorganism survives in weeds, so you can prevent it by removing any unwanted plants from your garden. You can also prevent the fungus by keeping your garden at a lower moisture level.

The affected crops can spread Anthracnose to the healthy ones, so you need to remove the infected crops from your garden to control the disease from spreading. You can try suitable fungicides to kill the pathogen.

Damping-off

This is caused by fungus that leads to decay and wilt in seeds and seedlings respectively. The infected seedlings have light brown stems. The pathogen survives in cold and wet soils, so you need to keep the soil temperature and moisture at optimum levels to prevent occurrence of this disease in your garden.

You need also to use certified seeds. You should immediately disinfect your soil if you notice any symptoms of the infection. You should also dispose of any infected seeds or seedlings. Besides, you can use a suitable fungicide to treat the infected crops.

Black rot

This is caused by both fungi and bacteria. It brings about yellow patches on the leaves of the infected crop. With time, the patches turn brown. The pathogen spreads to the veins and midribs of leaves and the stem, making them black. The harmful microorganism can be introduced to your garden by contaminated equipment, irrigation water or plant materials. You can, therefore, prevent it by ensuring that anything you bring to your garden is disease-free. You can control black rot by removing any infected crop from your garden.

You can also practise crop rotation to prevent the buildup of the disease with seasons. Leafy vegetable diseases are many, but these are the most common ones.  

[email protected]