Joint International Conference on Long-term Experiments ...

Table 2 The effect of provenance and developmental stage of explant upon the rate of
embryogenic induction in Q. robur (test Duncan)
Nr.
crt.
Stage of explants
(zygotic
embryos)
Provenance
Embryogenic induction and its significance*
S1 S2 S3 S4
Average on
provenances
1 Tg. Mureş 0.88a 0.66abc 0.58bc 0.47c 0.65 A
2 Ştefăneşti 0.78ab 0.66abc 0.61bc 0.45c 0.63 A
3 Dumbrava Sibiului 0.73abc 0.64abc 0.48c 0.42c 0.57 B
Average on stages 0.80M 0.65N 0.56NP 0.44P
*Differences among any variants followed by one common letter are not significant.
DS 5% for the interaction between provenance and stage: 0,225-0,261.
DS 5% for provenance: 0,050-0,051.
DS 5% for the stage of explants: 0,134-0,145.
We can conclude that it is very important to harvest the acorns for somatic
embryogenesis experiments in early stages, and when it is not possible, to plant on
culture medium a big number of explants (5 fold more than usually), in order to ensure
the somatic embryo induction, despite of the very low efficiency.
It is also useful to preview a big number of explants when new provenances are tested,
because of their effect upon the embryogenesis.
Table 3 The effect of provenance and culture medium upon the rate of embryogenic
induction in Q. robur (test Duncan)
Nr.
crt.
Provenance
Culture
medium
Rate of embryo induction(%) and significance*
QE1 QE2 QE3 QE4
Average on
provenances
1 Tg. Mureş 0.64ab 0.65ab 0.65ab 0.65ab 0.65 A
2 Ştefăneşti 0.60ab 0.59ab 0.62ab 0.69a 0.63 A
3 Dumbrava Sibiului 0.57b 0.57b 0.55b 0.58b 0.57 B
Average on culture media 0,61M 0,60M 0,61M 0,64M
*Differences among any variants followed by one common letter are not significant.
DS 5% for the interaction between provenance and medium: 0,092-0,110.
DS 5% for provenance: 0,050-0,051.
DS 5% for culture medium: 0,184-0,200.
As it can be seen in the table 3, the effect of culture medium upon the rate of embryo
induction was insignificant, despite of some differences among provenances.
We can conclude that the composition of culture medium was not a limitative
factor, media with different nutritive compositions and auxin/cytokinin ratios of 5/1
(QE1, QE3) and 1/1 (QE2, QE4) being equally suitable for the induction of somatic
embryogenesis.
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