DEAD FLOWER BUDS ON ‘CONFERENCE’ PEAR TREES: PROPOSAL OF A SOLUTION

The phenomenon of dead flower buds on pear trees has been observed for many years and been seen to reduce significantly the productivity of the fruit trees in some years.
The frequency of dead flower buds can vary significantly from one year to another and young pear trees are considered to be more susceptible than older trees from the same pear cultivar.
There is apparently a climatic influence during the season on the phenomenon; a warm period at the end of the season in autumn followed by a sudden frost has often been seen as a determining factor, inducing the occurrence of dead flower buds.
However, dead flower buds were found on young Conference trees in the winter 2006/2007 without any clear frost interference.
There seems to be a varietal response for this phenomenon: the pear cultivar ‘Doyenne du Comice’ seems to be less susceptible than the pear cultivar ‘Conference’. The real reason for the phenomenon of the dead flower buds is not clearly understood today.
The internal tissue of the flower buds becomes damaged by frost and an infection follows.
It is not clear whether this infection is a bacterial infection caused by Pseudomonas syringae pv. syringae or a straight or additional fungal infection caused by Alternaria alternate. In this study the efficacy of the systemic fungicide fosetyl-Al (Aliette) as an inducer of plant defence reactions is studied.
Application of the systemic compound in the period of May–June, when flower buds are initiated, was evaluated against the phenomenon of the dead flower buds during the following winter.
The results of these trials will be discussed in this paper.

X International Pear Symposium

T. Deckers, H. Schoofs, P. Creemers, M.P. Latorse, D. Rosati, L. De Maeyer

dead flower buds, pear, fosetyl-Al

https://doi.org/10.17660/ActaHortic.2008.800.115