|Authors: ||R. Sestras, C. Botez, M. Ardelean, I. Oltean, A. Sestras|
|Keywords: ||breeding, genotypes, pear, psylla, resistance|
The response of different pear genotypes to Psylla sp. (Cacopsylla) attack in natural conditions of infestation was studied in the experimental field of Cluj-Napoca Fruit Research Station, Romania, on more than 10,000 cultivars, selections, and hybrids.
Most cultivars were susceptible to Psylla attack, including the most important and widely spread in Transylvania: ‘Williams’, ‘Conference’, ‘Beurré Bosc’, ‘Beurré Hardy’, ‘Clapp’s Favorite’, ‘Curé’, etc., which represent more than 80% of the total cultivars and selections analyzed.
Several cultivars were identified as weakly susceptible: ‘Cantari’, ‘Imperiale’, ‘Lorencz Kovacs’, ‘Triomphe de Jodoigne’, ‘Severianka’ etc., most of them being ancient cultivars, with a poor productivity and quality and susceptibility to scab (Venturia pirina). One of the cultivar released at Cluj-Napoca, named ‘Haydeea’, expressed a good response in conditions of very severe Psylla attack.
In a comparative trial, ‘Haydeea’ had a fruit yield significantly higher than other cultivars and selections.
The vegetation of ‘Haydeea’ was relatively normal, while the trees of other cultivars had few fruits and lost their foliage.
After a heavy infestation period with Psylla sp., severe symptoms of tree scorching were noticed.
The cultivar, together with the rootstock and the cultivar x rootstock combination, had a significant influence upon the expression of pear tree scorching, consecutive to the infestation with Cacopsylla.
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