Protocols for Micropropagation of Woody Trees and Fruits

Shoot length (cm)
1.8
1.6
1.4
1.2
0.8
0.6
0.4
0.2
IN VITRO SHOOT DEVELOPMENT OF TAXUS WALLICHIANA ZUCC.
Figure 4. The average shoot length (cm) of T. wallichiana explants on different modified MS
media without activated charcoal.
2.4.2. Initial Explants for Shoot Growth
Newly-sterilized shoots are preferred in shoot growth in in vitro conditions. The
newly-sterilized shoots and the in vitro 7-week-old shoots and stems were transplanted
to C10 and C11 media. After 10 weeks of cultures, all the ex vitro explants
grew very well, the needles were green; whereas the initial in vitro 7-week-old
explants showed no growth and had yellowish needles. This is possibly due to their
previous physiological states as well as their growth conditions (Table 5).
2.5. Bud Induction
1
0
C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11
Medium
Place young stems 1.5–2 cm in length on culture media. Cytokinins are essential for
the induction of adventitious bud primordia in conifers. Among the cytokinins, BA
was found to be the most effective for inducing shoots from stem culture of Taxus
mairei seedlings (Chang et al., 2001).
The induction and multiplication of adventitious buds from young stems were
surveyed on AB1 (containing 1 mg.l –1 BA) and AB4 medium (containing 1 mg.l –1
BA and 2 g.l –1 activated charcoal). 22.4% of the explants formed adventitious buds
on AB1 medium after 6 weeks in culture. Among them, 0.9% of explants had two
buds and 3.45% of the new buds elongated to the average length of about 0.75 cm.
Some explants were bloated and formed small calli at their cut ends. 18% of
explants induced adventitious buds on AB4 medium; in which 3.33% of the new
buds elongated to the average length of about 1.3 cm.
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