How the harmful fungus Ustilago maydis able to form in the aerial parts of the corn plant and weakens it has been investigated by a research team led by the University of Bonn.

According to the experts, the release of molecules by the fungus known as effectors, which control the metabolism of the plant and suppress its immune defenses, causes enormous tumor-like tissue growths--known as galls--to form at the site of the infection.

Smut is a plant disease that primarily affects grasses, such as corn (maize), wheat, sugarcane, and sorghum, and is brought on by various fungi species.

Although in Mexico, the immature galls of infected ears of corn are eaten as a delicacy recognized as huitlacoche, the disease lessens corn yields and can result in economic losses.

Interaction of Ustilago maydis fungi to Corn Plants
(Photo : Jesse Gardner/Unsplash)

Armin Djamei, a specialist in plant pathology at the University of Bonn, is the study's senior author.

The fungus uses an auxin signaling pathway to serve its own purposes, as per Earth.com.

Therefore, they were interested in learning how the fungus encourages these processes of proliferation.

To accomplish this, they looked for genetic components in the fungus that would allow it to regulate the auxin signaling pathway of its host plant and thereby its cell growth.

This is due to the enormous tissue growth that uses resources and energy that would otherwise be needed for Ustilago maydis defense..

The lead author, Janos Bindics, a researcher at the IMBA Institute of Molecular Biotechnology in Vienna, explained that the proteins encoded by five Tip genes can bind to a protein in the corn plant is also known to experts as Topless.

Topless is a key switch in the plant that inhibits a number of signaling pathways.

This suppression is overridden by the fungus-specific effectors made by the Tip gene cluster, especially for auxin- and other helpful signaling pathways.

Further study is required to better comprehend the infection process in various plant diseases because a variety of pathogens disrupt the auxin signaling pathways of both the host plants that they infect.

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Corn Smut

Corn smut is a plant disease that affects teosinte and corn (maize) plants and is brought on by the fungus Ustilago maydis, as per Britannica.

Any above-ground plant part can be affected by corn smut, and symptoms only appear where the infection is present.

Although heavily infected plants frequently look distorted, corn smut is typically not fatal.

White galls that later burst to start releasing dark spores that can infect other corn plants are the first signs of an attack.

Warmer weather is when the illness is most active.

The spores infect the planting the following year after overwintering in the soil and also in corn litter.

Corn smut cannot be chemically controlled, but it can be kept in check by trying to remove galls before they mature and removing corn litter every fall.

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