Protocols for Micropropagation of Woody Trees and Fruits

CHAPTER 8
PROTOCOL FOR MICROPROPAGATION
OF QUERCUS spp.
M.G. OSTROLUCKÁ, A. GAJDOŠOVÁ AND G. LIBIAKOVÁ
Institute of Plant Genetics and Biotechnology SAS, Akademická 2, P.O. Box 39A,
950 07 Nitra, Slovak Republic; E-mail: gabriela.ostrolucka@savba.sk
1. INTRODUCTION
Oaks are important broad-leaved hardwood species of forest ecosystems, valuable
from economical and ecological point of view. The preferred means of oak propagation
is from seeds, what favours broadening of genetic diversity of these species.
However, the possibilities of generative reproduction are limited by long life span
necessary for achievement of physiological maturity, by irregular occurrence of mast
years, by low crop and quality of seeds and difficulties in acorn storage. Seeds of
Quercus species show different degrees of recalcitrance and can be stored only for a
short period because of their sensitivity to desiccation. In addition, the conventional
method of vegetative propagation of mature trees by cuttings is associated with difficulties
in rooting.
The problems in oak propagation from juvenile or mature material could be
solved by the use of in vitro techniques. In vitro propagation from dormant buds
collected from mature trees is important especially for the commercial forestry, for
clonal propagation of selected genotypes with valuable wood quality, resistant or
tolerant to diseases and to conditions with increased pollution. In vitro propagation
from juvenile material enables production of large number of vital plants of diverse
genotypes necessary for the maintenance of genetic diversity in forest ecosystems.
Immature and mature zygotic embryos are potentially suitable sources of explants
for oak micropropagation. The cultures of excised embryos are practical and effective
techniques of in vitro propagation. Using them the premature abortion of zygotic
embryos, derived from open or controlled pollination, can be overcome and also their
dormancy can be reduced or broken. In this chapter, the micropropagation protocol
for Quercus spp. using explants from juvenile material (embryos and seedlings), as
well as from selected mature trees is described.
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S.M. Jain and H. Häggman (eds.), Protocols for Micropropagation of Woody Trees and Fruits, 85–91.
© 2007 Springer.