How To Recognize Oat Diseases?

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

Everyone who grows oats sooner or later is faced with various diseases of this crop. However, making an appropriate "diagnosis" is often quite problematic. To facilitate this task, you need to familiarize yourself with the main symptoms of the most common ailments. And then it will not be difficult to distinguish between dusty and covered smut or crown rust from stem rust

Powdery mildew

This attack is especially harmful in the forest-steppe and in the steppe. The stalks and leaves of oats are covered with a cobweb bloom of characteristic whitish shades, which gradually begins to thicken and become covered with tiny black dots.

Hard smut

A ubiquitous ailment that manifests itself mainly in the defeat of the panicles, which in a fairly short time turn into a very dark and extremely unpleasant mass of spores. As a result, only thin silvery outer films, slightly covered with harmful teliospores, remain from the spikelet scales. For this, the hard smut is also called covered. Most often, this infection attacks oats at the stage of seed germination.

Dusty smut

All infected parts of the panicles are destroyed rather quickly and look like a black dusty mass of spores. The harmfulness of this scourge lies in a significant shortage of the long-awaited harvest (for late sowing, this is especially true).

Stem (linear) rust

This disease can be encountered at the stage of milk or wax ripeness of the seeds. On the stalks and on the leaves of oats, oblong, rusty-brown uredinia are formed, slowly joining together. And closer to the end of the growing season, in places where spots appear, black telia begin to develop - such lesions have the form of black stripes up to twenty-two centimeters long. The lack of grains as a result of stem rust damage often reaches 60%.

Reddish-brown spotting

This ailment affects not only the leaves, but also flower and spikelet scales. And sometimes this attack can also attack the seeds. On the infected organs of oats, the formation of oblong brownish or dark gray spots, framed with reddish rims, is noted. On the sides, such spots are delimited by clearly distinguishable veins, and their edges are always much darker than the middle. The formed spots do not merge, and the tissues in the places of their formation do not break, but when wet weather is established, a characteristic olive bloom may appear on them. Dried infected leaves fall off rather quickly. And if flower or spikelet scales are affected, then the grains formed on them will be puny and unsightly.

Crown rust

This infection manifests itself either immediately after throwing out the panicles, or at the beginning of the filling of the grains. On the leaves of oats, and slightly less often on its stems, the formation of oval or rounded orangeish scattered uredinia occurs. On average, their diameter reaches 0.5 mm. If the lesion is too strong, then the uredinia will begin to form in an incomprehensible form of tubercles. At first, they are all covered with the epidermis, but after some time, the uredinia rupture, and destructive urediniospores are released from them. And after a week and a half, shiny black telia appear around them, looking like small stripes of dark brown color.

Bacterial leaf burn

Characteristic light brown, even slightly reddish spots appear on oat leaves. At first they are round and very small, and a little later all the spots stretch out in the form of narrow stripes. The diseased leaves turn red and dry out after a while. Most often, this attack is manifested by foci. It is especially sad that there are no varieties of oats resistant to this disease.