Benefiting from the past: establishing in vitro culture of European beech (Fagus sylvatica L.) from provenance trial trees and seedlings

Table 3 Effects of sampling date on contamination and shoot formation rates

Sampling date	N provenances	N genotypes	Σ samples %	Contamination %	Shoot formation %
Feb	5	10	137	27^a	5^a
Mixed	5	13	271	48^b	18^b
May	12	18	283	69^c	16^ab

Branches were collected in February (Feb) and/or May. Among the Feb samples, 244 samples were derived from bud break under GH conditions, and 29 were derived from bud break under PGC conditions. For the mixed samples (Feb/May), the same number of samples (± 4 explants) were derived from the Feb or May samples. Shoot formation rates were calculated after the exclusion of contaminated explants. Values with different letters are significantly different according to the pairwise Pearson’s chi-squared test with p < 0.05

ISSN: 1746-4811