COMPARISON BETWEEN TWO METHODS OF SELECTION FOR RESISTANCE TO ERWINIA AMYLOVORA IN YOUNG SEEDLINGS OF PEAR

Ten parents were crossed with the old French variety ‘Pierre Corneille’ (Pyrus communis) in order to find a pear variety not too susceptible to fire blight.
The ten parents were:

1. European varieties,

2. U.S. varieties,

3. U.S. and Canadian selections.

These ten parents and the common parent ‘Pierre Corneille’ were all previously observed in State or Canada for their low susceptibility.

The progenies were divided in two parts and the selection for resistance was performed according to two ways :

1. in glasshouse after inoculation on young seedlings in their first year of growing, on only one shoot.

2. in the orchard, after inoculation of fifteen shoots (5 shoots x 3 years) on 3 to 5 year old seedlings.

The two methods are compared taking as criteria the index of susceptibility (Severity x Frequency) and the rate of selection.

IV International Workshop on Fire Blight

B. THIBAULT, P. LECOMTE, L. HERMANN, A. BELOUIN

https://doi.org/10.17660/ActaHortic.1987.217.46