Protocols for Micropropagation of Woody Trees and Fruits

CHAPTER 4
MICROPROPAGATION OF PINUS PINEA L.
R.J. ORDÁS, P. ALONSO, C. CUESTA, M. CORTIZO,
A. RODRÍGUEZ AND B. FERNÁNDEZ
Unidad de Fisiología Vegetal. Instituto de Biotecnología de Asturias. Universidad
de Oviedo. E-33071 Oviedo. Spain
1. INTRODUCTION
Stone pine (Pinus pinea L.) is an economically important tree in the Mediterranean
area, and has a significant role in soil conservation, landscape architecture, and for
its edible seeds. This makes many aspects of its management similar to an agronomic
tree. The wide potential for improvement and the great economic value of the
pine nuts requires utmost attention to develop genetic breeding programs. These
programs are based on the identification of excellent genotypes by establishing
clonal banks of different provenances. Due to the fact that conventional techniques
of asexual propagation do not work with P. pinea, grafting is the only method available
to propagate and genetically evaluate individual clones. However, grafting is
far from being optimal. Evaluating the same clone grafted on different rootstocks
generates high variability due to scion–rootstock interaction that varies production
levels (Mutke et al., 2000). The use of clonal rootstocks could allow to even this
interaction, enabling a much more reliable evaluation of each clone.
The heritability of seed characters such as length, number per cone and cone
weight is high (Oliveira et al., 2003) and that makes the main objective of its genetic
improvement to enhance the quantity and quality of seed production per tree. Therefore,
the production of clonal plants from selected seeds by micropropagation would
be a desirable tool to improve genetic breeding programs and a means to establish
high yield plantations.
In vitro micropropagation of this coniferous species via organogenesis has been
extensively studied (García-Férriz et al., 1994; Capuana & Giannini, 1995; González
et al., 1998; Oliveira et al., 2003; Sul & Korban, 2004). The micropropagation
system is based on the induction of shoot buds in cotyledonary explants dissected
from non-germinated embryos (Valdés et al., 2001) and cultured in the medium
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S.M. Jain and H. Häggman (eds.), Protocols for Micropropagation of Woody Trees and Fruits, 33–39.
© 2007 Springer.