It’s a fungal disease that leads to the formation of a grey, powdery coating on the surface of leaves, buds, flowers and even fruits. It is caused by a wide range of fungi species that fall in the genera Erysiphe, Microsphaera, Phyllactinia, Podosphaera, Sphaerotheca, and Uncinula. These fungi have a fairly narrow host range, which means that they only attack specific plant species such as edible and garden plants, as well as horticultural and agricultural plants. Furthermore, they thrive in soil with insufficient moisture and in humid weather. Infected plants show grey powder-like spots on leaves and stems. In acute cases, the affected plant parts exhibit disfigurement and stunted growth while the leaves turn yellow and wither away.
Symptoms & indications
1. Leaves covered in white powdery spots (sometimes, the fungal growth is only visible on the lower surface of the leaves).
2. Distorted and stunted growth in plants.
3. In some cases, the infected plant parts turn dark brown.
1. First and foremost, it is important to get rid of the infected shoots. Prune off the affected shoots and dispose of them properly. Do not forget to sterilize the contaminated shears after pruning.
2. Destroy the infected, fallen leaves to prevent the spread of the disease.
3. Water the plants regularly as it reduces the risk of infection.
4. Cover the soil with a thick layer of mulch/organic compost as it prevents recurrence of infection.
5. Limit the use of nitrogenous fertilizers, instead prefer slow-release organic-fertilizers.
6. Sulfur works against the fungus but is not effective in high temperature weather conditions.
7. Copper-based fungicides, baking soda solutions, and neem oil are also effective treatments for this fungal infection.
8. Use resistant varieties of plants.