Pink root rot – disease of onion and garlic

Pink causative agent of garlic root rot is a soil fungus Phoma terrestris. Most often the disease manifests itself in the southern regions.



Name –

of agent:

soil fungus Phoma terrestris


  • Setophoma terrestris (H. N. Hansen) Gruyter, Aveskamp, & Verkley
  • Phoma terrestris [H. N. Hansen] Gruyter, Aveskamp, & Verkley;
  • Pyrenochaeta terrestris [H. N. Hansen] Gorenz, J. C. Walker, & Larson)


  • Pink rot root, root pink bow
  • Spanish: Raíz rosada, Mancha rosada

гриб Phoma terrestris       



The most notable symptom Pink rot the roots, as the name implies, is a pink roots.

Infected roots are initially light – pink, then darken and become red and violet, shrivel, turn black and die.

Pink and red can spread up the scale of the bulb. New roots may also become infected. If the infection continues, the plant begins to wither.

The disease often leads to the death of plants. The infection is limited to external scales roots and bulbs.

It should be noted that fungi Fusarium, which cause Fusarium can also be a symptom of a pink roots. Especially in older, well-established roots.

Pink root rot usually occurs on plants that are in the stage of active growth.

розовая гниль корня лука, фото симптомов



Comments to the disease

Pink root rot – a disease usually onions. Garlic is also exposed to this disease, but the disease it is rare to economically unsafe level.

The fungus is a common inhabitant of soil, which penetrates the roots of onions or garlic directly. That is, he does not need to infect the wound. However, weak plants are much more susceptible to infection.

The causative agent can be stored indefinitely in the soil; the longer the bulbs grown in the field, the more devastating the disease becomes. The fungus can spread through water jets and rain dirty equipment.

The optimum temperature for disease development ranges from 25 ° to 30 ° C.

Pink root rot affected plants become more susceptible to defeat other fungi. Those large yield losses may occur in the case of complex diseases of the species Fusarium, Pithium, Rhizoctonia and Helminthosporium. (Fusarium, Banning of seedlings, black scab, scab silver)

розовая гниль корня лука, фото симптомов


Preventing and combating the disease root rot Pink


Crop rotation. However, due to the fact that many plants are carriers of the disease, the effectiveness of this method is not high

Front-of-the-front section of the landing material



Methods of combating disease

Options fungicides to combat root rot pink garlic (used in the general system of protection against diseases):

  • Kvadris production Syngenta, Switzerland. The active substance of 250 g / l Azoksystrobyn. The consumption rate of 0.6 l / ha.

The video – a growing root of the garlic cloves in accelerated motion




  • David B. Langston, University of Georgia
  • Howard F. Schwartz, Colorado State University


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