agronom.me
Menu

Seeds and varieties

Globe thistle as a dangerous toxic weed of crops

For agronomists

2 min read

Great globe thistle is a dangerous weed that infests crops of cereal crops. The plant is widely distributed in the central and southern regions of the European part, in Crimea, the Caucasus, Western Siberia, and Central Asia. In addition to infesting grain fields, the object poses a high risk due to the toxicity of the seed material.

The seeds of the globe thistle are poisonous: they contain the alkaloids echinopsine and echinopseine. Echinopsine has anticholinesterase activity, increases the reflex excitability of the spinal cord and has a convulsive effect, and in toxic doses, it lowers blood pressure. The main symptoms of poisoning include nausea, vomiting, diarrhea, hyperreflexia, increased tone of the occipital muscles, and convulsions. In severe cases, spasms of the respiratory muscles occur, which can lead to complete respiratory arrest.

Morphological characteristics and dimensions of achenes

Семянка в обвертке мордовника шароголового
Achene in the involucre of the great globe thistle

To identify the weed in sowing material and grain bulk, it is necessary to take into account the structural features of the achenes with and without the involucre. Achenes in the involucre have a wedge-shaped form and a pubescent surface of gray, yellowish-gray, or grayish-green color. The involucre itself consists of three rows: the outer (composed of thin spine-like soft bristles), the middle (composed of lanceolate leaflets of the same length), and the inner (composed of long keeled leaflets significantly exceeding the achene).

Cleaned achenes are cylindrical, elongated-cylindrical, slightly compressed, colored light yellow, yellowish-gray, or pale. Their surface is wrinkled, slightly pubescent, and covered with small, easily erasable hairs. On the truncate apex along the edge, there is a crown of small bristles, and the fruit scar is central, small, and round in shape.

Condition of the achene Length, mm Width, mm Thickness, mm
In the involucre 1012 45 34
Without the involucre (naked) 68 34 23

In addition to the great globe thistle, other representatives of this genus exhibit similar toxicity:

  • southern globe thistle;
  • Russian globe thistle;
  • Gmelin's globe thistle;
  • Dahurian globe thistle.

Read next