WHITE SPOTS IN HAZELNUT KERNEL: SYMPTOMS, CAUSES AND QUALITY LOSS

In order to determine the origin of white spots in hazelnut kernels, several studies were carried out from 2004 to 2006. These studies included hazelnut sampling at different ripening times, different cultivars, insect trapping, microscopic and macroscopic studies of affected kernels and several preventative strategies for hazelnut trees.
Fruit sampling at different dates showed that the affection begins at the end of July (in Catalonia, Spain), when the kernel is fully developed and the shell is almost lignified.
Microscopic studies revealed that biting insects are the cause of the white spots, while trapping and protective studies pointed out that the bugs Nezara viridula L., Palomena prasina L. and possibly other secondary bugs are responsible for kernel white spots.
Significant differences in damage can be expected between zones and years.
Future studies will consider chemical spraying on hazelnut trees at various stages, with different products, in order to prevent green bug attacks on hazelnut kernels.

VII International Congress on Hazelnut

A. Romero, J. Tous, E. Martí

green bugs, Nezara viridula, Palomena prasina, feeding activity

https://doi.org/10.17660/ActaHortic.2009.845.95