Plant Fungus Diseases

Fungal disease is the common cause of poor health and yield of plants. University of Texas at Austin states that 70 percent of all the plant diseases are caused by fungi. Some fungal diseases in plants also affect humans significantly. An excellent example would be the infamous Irish potato famine in the 1840s that was responsible for 750,000 human deaths.

Potato Blight

The fungus Phytophthora infestans is responsible for this common plant disease. It spreads rapidly through many parts of the potato plant and causes speedy death of the invaded tissue. In many cases, the stem or the potato fruit itself gets infected, and this can cause the death of the entire plant.


Rusting of crops is another common fungal plant disease that causes widespread plant destruction. This fungal plant disease usually infects leaves, seeds or the fruit of the plant and causes powdering up of the produce. While the disease does not kill the host plant, it completely destroys its produce. With over 6,000 species of rust fungi affecting plants, ranging from staple crops to coffee and fruit bushes, rust is the most widespread of plant diseases.


Smut or spore formation has led to immense losses to agriculture in the past, the the American Phytopathological Society states. These fungal plant diseases can be easily identified by the sootlike substance that is actually fungal spores. These spores accumulate on the galls of plants like corn. While not dangerous to humans, this disease slowly kills the plant from within, causing it to wilt and droop. Since most of the nutrition is used up by the fungi, the fruit formation is severely inhibited.

Root Rots

Unlike other plant fungal diseases, root rot can affect even big plants and trees, causing immense damage to them. Often occurring due to insufficient sunlight or aeration of the soil, it affects the roots and root hair of the plants. Even big trees like oaks are known to succumb to root rot and have fallen over because their roots have been eaten up by fungi. This plant disease has caused significant losses to carrot farmers in countries like New Zealand, the Ministry of Agriculture and Forestry, New Zealand, states.


Plant mold is another fungal plant disease that slowly eats up the stem of the plant. In smaller plants, the disease can be observed on the leaves and flowers, where it causes discoloration and wilting. Often the result of damp weather and inadequate exposure to sunlight, mold affects barks of trees too. The spores are poisonous and can easily spread through the air.

Keywords: fungal disease plants, plant fungal diseases, fungal diseases

About this Author

Based in Northern California, Devin Dupre-Neary has a bachelor's degree in nursing from UC Davis. Rather than move towards a master's or work in a hospital, he chose a different route. In 2009, he wrote professionally, part-time, writing articles on a host of subjects from health issues to gardening.