Basal Rot (caused
Symptoms and damage
This is the most serious daffodil bulb disease
which although it was described a hundred years ago as a serious threat, is
growing in intensity as a result of hotter summers. The initial symptoms is the
premature dying back of the foliage which when investigated, or at lifting
time, reveals a soft or mummified bulb containing a chocolate brown rot
spreading upwards from the base plate. At this point recovery of the bulb
usually becomes impossible. The bulbs can become infected in storage or after
planting and spores become widespread and are viable for over ten years in the
Control is very difficult even commercially.
Resistant cultivars such as St Kevern are grown, but even these are not immune.
The avoidance of fresh manure or excessive nitrogen is essential and the early
lifting of the bulbs is preferred. These should immediately be sprayed with a
suitable fungicide and dried rapidly in a good air-flow by using electric fans.
Storage should then be at a low temperature of 17-18C (62-64F) with planting in
late September or early October when soil temperatures are lower. Bulbs in
storage should be inspected regularly and soft ones destroyed.