Basal rot of Narcissus (daffodils) is a fungal infection which decays the base of the bulb, often during winter storage. If infected bulbs are planted, the resulting growth is yellow and may not flower.
Basal rot is one of the most serious diseases of daffodils and is caused by the soil-borne fungus Fusarium oxysporum f. sp. narcissi. The fungus enters the bulb initially by rotting roots, or directly through weaknesses in the base. Look for symptoms whenever the growing bulbs fail and on lifted, stored bulbs.
The disease is very difficult to detect in its early stages. As the brown, spreading rot develops, the bulb feels slightly soft.
You may see the following symptoms:
There are no chemical controls available.
The fungus Fusarium oxysporum is very common in the soil, where the majority of the population lives as a saprophyte (a harmless organism that feeds by decaying dead organic matter). However it also has a large number of pathogenic strains, which are able to infect different plants.
Fusarium oxysporum f. sp. narcissi only infects Narcissus. It is found in the soil, even where Narcissus have not been grown previously, and can be found on the surface of bulbs even when these are apparently healthy. Infections occur through wounds or weaknesses, such as the point at which young roots grow out into the soil from the base of the bulb.
Neck rot occurs when infection enters around the neck, often after flowering has finished.
Infection is sometimes associated with attack by the stem nematode (eelworm) Ditylenchus dipsaci, but the two problems may also occur independently.
BulbsBulbs: naturalisingBulbs: plantingDaffodilsDaffodil virusesNarcissus bulb flyNarcissus eelwormNarcissus leaf scorch
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anonymous on 26/06/2014
I garden in Germany and have a problem with what I think is Basal Rot. My garden has been built on old forest land . So I think the infection is endemic. What bulbs have a strong resistance to this fungal infection.
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