Bubble Smut In Corn

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

Bubble smut attacks corn in most of its cultivation areas. It differs from the dust smut in that it manifests itself in the form of galls (as pathological formations are called) on all organs of corn. Often such galls can be seen on cobs with leaves. Corn is considered the most susceptible to this ill-fated misfortune at the stage from the moment of throwing out panicles and up to the stage of milk ripeness, therefore, during this period, special care should be taken, otherwise yield losses can reach 25 - 30%, and in dry conditions - even 50%

A few words about the disease

With the defeat of corn leaves, you can observe the appearance of swellings that resemble a group of rough wrinkles in appearance. And in panicles, isolated flowers are mainly affected, on which the formation of small saccular swellings begins. At the same time, rather large galls are formed on the cobs with stalks, in which fungal teliospores develop. The spores that mature in such galls slowly germinate and attack the corn throughout the growing season. The finally matured swellings consist of black spore masses covered with grayish and shiny fleshy membranes.

With the onset of autumn, smut bumps often break off when harvesting corn and often overwinter in corn fields. And in the spring, the activated spores again infect the plants.

The causative agent of blister smut is a basidiomycete called Ustilago zeae Unger. When its mycelium matures, many harmful spores are formed. In mass, they are usually colored in black-olive tones, and spores located one by one have a spherical shape and are colored yellow-brown. They are often endowed with large bristles and are decorated with a mesh pattern.

To a large extent, the development of the ill-fated misfortune is facilitated by thickened crops, small precipitation during the period of infection and dry weather. This disease is especially harmful when it affects corn stalks with cobs. Affects its development and soil moisture. The plants are much less affected in the case of moderate humidity. But with high or low soil moisture, their susceptibility will be much higher. Increase the susceptibility and sharp fluctuations in moisture - this feature is important to consider if corn is cultivated on irrigated land.

Maize attacked by bubble smut is much more susceptible to stem rot. And if this dangerous disease covers young plants, they can easily die. And in general, the harmfulness of this scourge is very high, because it provokes infertility of the ears and a significant shortage of harvest (sometimes up to 60%).

Often, bubble smut in corn can be encountered in areas with insufficient or unstable moisture, as well as in the south of the European part of the former USSR.

As for the toxicity of the growths formed as a result of the defeat of the bladder smut, here the opinions of biologists differ. Most of them believe that young growths in the absence of teliospores in them cannot be poisonous, but old formations filled with a huge amount of teliospores are comparable in toxicity to ergot.

How to fight

The main protective measures against harmful bladder smut are the selection of healthy and strong seed cobs and the timely removal of post-harvest residues from the areas.

Seed dressing can help solve the problem of seed infection. The Lanta treater copes well with this task. And the seeds should be sown only in well-warmed soil. However, it is important not to forget that infection can occur later. The selection of resistant hybrids, as well as their proper spatial isolation, will also be an effective means of control.