A POSSIBLE EXPLANATION OF VARIATIONS IN SUSCEPTIBILITY OF TULIP BULBS TO INFECTION BY FUSARIUM OXYSPORUM

In tulip-bulb production in The Netherlands, infection of young growing bulbs by Fusarium oxysporum f. tulipae occurs mainly during the last few weeks before they are harvested.
Although climatic conditions (especially soil temperature) greatly influence disease incidence, these factors are not responsible for the phenomenon mentioned.

Extracts of the outermost scale (the bulb skin) contain tulipalin (-methylene butyrolactone), a compound which is fungitoxic in vitro, but as soon as the skin has become a leathery brown husk, no growth-inhibiting effect can be demonstrated in the extract.

The same compound is found in extracts made from the first fleshy scale, but in widely varying concentrations.
The probable relationship between these varying yields of fungitoxic substance and the incidence of the disease are discussed.

I International Symposium on Flowerbulbs

B.H.H. Bergman, J.C.M. Beijersbergen

https://doi.org/10.17660/ActaHortic.1971.23.35