J. Sedlak, F. Paprstein
The goal of this study was to develop a method for rapid in vitro shoot multiplication of five older pear cultivars and landraces (‘Beurre de Merode’, ‘Grise Bonne’, ‘Holzfarbige Butterbirne’, ‘Jakubka ceska’, ‘Solanka’). Six proliferation MS media containing different concentrations of cytokinins BAP (6-benzyl-aminopurine), TDZ (thidiazuron) or 2iP 6-(gamma,gamma-Dimethylallylamino) purine were tested. For the five genotypes, the effect of three growth regulators on proliferation, callus formation and shoot morphology is shown. Selected pear cultivars were successfully established in vitro using mercuric chloride in a concentration of 0.15% as a sterilization solution. Of the 100 shoot tips taken only 1 explant of ‘Holzfarbige Butterbirne’ and 6 explants of ‘Solanka’ were visibly contaminated with microorganisms. The number of newly formed shoots varied with the cultivar and concentration of cytokinins. Generally, the highest proliferation rate was obtained for pear cultivar ‘Grise Bonne’ that produced 4.7 shoots (longer than 10 mm) on MS medium containing 1 mg L-1 TDZ. On the contrary, the lowest proliferation rates 1.0 were obtained for cultivars ‘Grise Bonne’ and ‘Solanka’, which almost did not multiply on MS medium containing the lowest concentration of BAP 1 mg L-1. Abundant callus formation at the base of explants and abnormally narrow undeveloped leaves were observed on the media containing TDZ. All in vitro plants of pear cultivars on MS medium with 10 mg L-1 2iP developed good foliage. The root induction was relatively low from 3 to 26% of in vitro rooted plants. On an average, NAA promoted rooting of more plants than IAA and IBA.
Sedlak, J. and Paprstein, F. (2012). MICROPROPAGATION OF OLD PEAR CULTIVARS. Acta Hortic. 961, 473-477
DOI: 10.17660/ActaHortic.2012.961.62
multiplication, explant, medium, Pyrus, in vitro

Acta Horticulturae