carnation Fusarium wilt

Symptoms

One-sided yellowing and wilting: shoots on one side of the plant go pale grey-green then straw-coloured while the other side stays green; stems show a brown streak in the vascular tissue when split lengthwise; the whole plant slowly collapses and dies. Symptoms worsen in warm soil.

Plants affected

• carnation

Easily confused with

• grey mould (Botrytis)

  How to tell them apart: Botrytis cinerea (grey mould) attacks the upper, exposed parts — petals, flower buds and soft stems — producing water-soaked tan-brown lesions that quickly become covered by a fuzzy grey-brown layer of fungal spores in humid weather; affected tissue collapses into a soft rot and dusty grey 'smoke' puffs up when touched. Fusarium oxysporum f.sp. dianthi (Fusarium wilt) is a soilborne vascular disease starting at the base: lower leaves and one side of the plant turn dull grey-green then yellow and curl, shoots wilt and dry to a straw colour, and there is NO grey fuzz. Slice the stem near soil level — Fusarium shows a brown-streaked discoloured ring inside the vascular tissue, which Botrytis never does. Botrytis follows wounds and high humidity from above; Fusarium spreads upward from the roots and worsens in warm soil.

Common questions

How do I recognise carnation Fusarium wilt on carnation?

One-sided yellowing and wilting: shoots on one side of the plant go pale grey-green then straw-coloured while the other side stays green; stems show a brown streak in the vascular tissue when split lengthwise; the whole plant slowly collapses and dies. Symptoms worsen in warm soil.

Do I have to report carnation Fusarium wilt?

No. carnation Fusarium wilt is not a notifiable organism, so there is nothing to report to an authority. Treat it as a normal garden problem.

How is carnation Fusarium wilt treated?

Mainly with biological and cultural measures — removing affected material, changing the conditions that favour it, and treating with agents approved in your country. The exact steps and their timing depend on the plant, the season and where you live: Dr. Phyto works them out in a free diagnosis.