Susceptibility of one-year-old shoots of scab-resistant apple cultivars to low temperatures in laboratory tests
during four winters (1999/2000-2002/2003)
Alojzy Czynczyk, Grzegorz Hodun, Małgorzata Hodun, Dorota Kruczyńska
Research Institute of Pomology and Floriculture
Pomologiczna 18, 96-100 Skierniewice, Poland
One-year-old shoots from 15 scab-resistant apple cultivars grafted on M.9 were
frozen artificially at temperatures from -15°C to -35°C during four successive winters from 1999/2000 to
2002/2003. During the winter of 1999/2000 the shoots were tested only once, in
the next two winters 3 times, and twice in the winter of 2002/2003. All the trees
from which the shoots were collected were planted in the orchard in the spring
of 1995. The injuries caused by low temperatures were assessed by means of a
survival test. The results obtained showed that the damage of one-year-old
shoots depended mainly on the degree of hardiness of the trees during the
dormant period and the cultivar. The injuries suffered by the shoots after
freezing during the four successive winters (1999-2003) showed that the
cultivars ‘Florina’, ‘Ligolina’, and ‘Ligol’ had winter hardiness similar to
that of the standard cultivar ‘Novamac’. The remaining cultivars were more
susceptible to low temperatures than ‘Novamac’. All the cultivars had lower
winter hardiness at the end of the mild winters of 2001 and 2002 in comparison with
the more severe 2003 one.
Czynczyk A., Hodun G., Hodun M., Kruczyńska D., 2004. Susceptibility of one-year-old shoots of
scab-resistant apple cultivars to low temperatures in laboratory tests during four winters (1999/2000-2002/2003).
Folia Horticulturae 16/1: 61-72.