ADAPTATION OF APPLE AND PEAR PLANTS TO IN VITRO CONDITIONS AND TO LOW TEMPERATURE

The conservation of pear (Pyrus communis) and apple (Malus domestica) genetic resources requires alternative techniques (cryopreservation) as a duplicate of the field genebanks.
Larger collection of cultivars was chosen according to their cold hardiness and their origin (including original Czech cultivars). Selected pear and apple cultivars were introduced to in vitro cultures.
Different cultivars did not respond in the same way during in vitro proliferation.
Multiplication rate after one month on MS medium with 1 mg l-1 BAP (6 – benzylaminopurine) varied from 1.2 to 5 depending on the cultivars.
Genotypes differ in shoot morphology (callus formation, narrow and not expanded leaves). In vitro cultures were subjected to cold hardening at + 4°C to enhance their tolerance to low temperature.
Their LT50 increased from –2°C to –5°C (non-treated plants) to –6°C to –13°C (cold treated plants) depending on the cultivar.
Cold hardened in vitro cultures and dormant buds were subjected to cryopreservation procedures.
Regeneration of cryopreserved plants is under investigation.
Cryopreserved pear and apple apices are stored in liquid nitrogen.

IV International Symposium on In Vitro Culture and Horticultural Breeding

J. Sedlák, F. Paprstein, A. Bilavcík, J. Zámecník

in vitro, apple, pear, micropropagation, cold hardening

https://doi.org/10.17660/ActaHortic.2001.560.90