THE ‘EVERGROWING’ GENOTYPE OF CORYLUS AVELLANA IS EXPRESSED IN THE OFFSPRING OF ‘TONDA GENTILE ROMANA’, ‘NOCCHIONE’ AND ‘TONDA DI GIFFONI’

The hazelnut (Corylus avellana L.) ‘evergrowing’ phenotype (EVG-d) fails both to cease growth and to enter dormancy under the dormancy-inducing (i.e., short days) conditions suitable for the EVG-D wild type.
The EVG-d phenotype is expressed by the homozygous genotype for the recessive allele d.
The EVG-d:EVG-D phenotypic ratio was 42:91 in half-sib progenies from seeds harvested on intercropped plants of ‘Tonda Gentile Romana’ (TGR) and ‘Nocchione’ (NOC), and 6:23 in the total half-sib and full-sib progenies involving ‘Tonda di Giffoni’ (TGIF) as seed parent.
In both cases there are no evidences of significant deviation from a 1:3 ratio, suggesting that the ‘TGR’, ‘NOC’ and ‘TGIF’ parental plants were heterozygous Dd at the ‘evergrowing’ locus.
The EVG-D plants start to exit dormancy and begin bud sprouting at 773 Utah chilling units.
The ‘evergrowing’ genotype does not require chilling units to sprout and might contribute to the expansion of the hazelnut crop in warm climatic region devoid of air temperature events below 0°C.

VII International Congress on Hazelnut

G. Catarcione, D. Vittori, M. Ciaffi, C. De Pace, E. Rugini

hazelnut, bud dormancy, plant breeding, non-dormant, Full Sib progeny, Utah chilling units, primary gene-pool

https://doi.org/10.17660/ActaHortic.2009.845.26