190
2000 additional seedlings. In turn, the large size of the seeds allowed a promising
restoration experience realized over 400 ha of burned A. araucana forests. In 1967,
the species was planted by dropping seeds from airplanes, estimating 49 years later
that 19% of the dispersed seeds produced advanced regeneration (Yacubson 1967;
Javier Sanguinetti, unpublished data). This recently evaluated experience encouraged the aerial seeding of A. araucana to be repeated in 2016, thus reaching burnt
sites with almost no accessibility (Mazzuchelli et al. 2016).
With growth rates as low as those observed in the established trials, especially
during the seedling and sapling stages, a classical improvement genetic programme
for A. araucana is hardly thinkable. However, conservation purposes currently
require planting the species, and thus, the genetic material to be used is of concern.
A low-intensity breeding programme should be considered. For such a programme,
it should be bear in mind that the seeds are characterized by rapidly losing their
viability due to dehydration (90 to 120 days); therefore, they are classified as recalcitrant seeds, i.e. they cannot be stored for long periods (Chaves et al. 1999). Another
characteristic of A. araucana seeds is that they present physiological dormancy, but
germinate relatively easily after winter, or when applying a pre-germinative treatment of cold stratification (López et al. 1986; Benítez 2005; Muñoz 2010).
Therefore, seeds are usually sown during the autumn, immediately after collection,
thus emulating the natural stratification conditions experienced during winter
(Gutiérrez 2019). Seed emergence at the nursery evaluated in 418 families of
A. araucana from Andean and Coastal ranges in Chile exceeded 80% 7 months after
sowing (Gutiérrez 2019). Lower values were reported for xeric populations of
Argentina (between 40 and 50% depending on the pre-germinative treatment,
Duplancic et al. (2015)).
Finally, it must be highlighted that the main use of A. araucana forests in the
whole history has been food provisioning. Animals and people have been eating its
pine nuts during 1000 years. Even introduced exotic animals as livestock (i.e. sheep,
cows, goats, horses) as well as feral animals (i.e. red deer, wild pigs) have been fed
on the species. In some forests, the tons of produced pine nuts feed the whole population of domestic and wild animals and constitute for some of them the main nourishment source of the whole system (Gallo et al. 2004b). Sometimes, the remaining
pine nuts for collection by the Mapuche communities are very scarce, since they
vary from year to year and are according to the different types of forests.
Consequently, a reasonable objective of a breeding programme for the species is
the pine nut production. There are trees in the natural forest that abundantly produce
cones and viable seeds almost every year. Their location is known by the usual collectors of pine nuts that belong to the Mapuche communities, and therefore, they
should be involved in the programme. Mass-selected trees can be propagated vegetatively by grafting on rootstocks of the same species in order to install clonal seed
orchards. This procedure is currently being conducted for Araucaria angustifolia in
the Manuel Belgrano Forest Station of INTA in the northeastern extreme of
Argentina (see Chap. 15). Such a breeding programme for the production of pine
nuts is being developed in Spain for Pinus pinea (Mutke Regneri et al. 2007).
Recently, several elite P. pinea clones and a clone mixture, selected for outstanding
P. Marchelli et al.
2000 additional seedlings. In turn, the large size of the seeds allowed a promising
restoration experience realized over 400 ha of burned A. araucana forests. In 1967,
the species was planted by dropping seeds from airplanes, estimating 49 years later
that 19% of the dispersed seeds produced advanced regeneration (Yacubson 1967;
Javier Sanguinetti, unpublished data). This recently evaluated experience encouraged the aerial seeding of A. araucana to be repeated in 2016, thus reaching burnt
sites with almost no accessibility (Mazzuchelli et al. 2016).
With growth rates as low as those observed in the established trials, especially
during the seedling and sapling stages, a classical improvement genetic programme
for A. araucana is hardly thinkable. However, conservation purposes currently
require planting the species, and thus, the genetic material to be used is of concern.
A low-intensity breeding programme should be considered. For such a programme,
it should be bear in mind that the seeds are characterized by rapidly losing their
viability due to dehydration (90 to 120 days); therefore, they are classified as recalcitrant seeds, i.e. they cannot be stored for long periods (Chaves et al. 1999). Another
characteristic of A. araucana seeds is that they present physiological dormancy, but
germinate relatively easily after winter, or when applying a pre-germinative treatment of cold stratification (López et al. 1986; Benítez 2005; Muñoz 2010).
Therefore, seeds are usually sown during the autumn, immediately after collection,
thus emulating the natural stratification conditions experienced during winter
(Gutiérrez 2019). Seed emergence at the nursery evaluated in 418 families of
A. araucana from Andean and Coastal ranges in Chile exceeded 80% 7 months after
sowing (Gutiérrez 2019). Lower values were reported for xeric populations of
Argentina (between 40 and 50% depending on the pre-germinative treatment,
Duplancic et al. (2015)).
Finally, it must be highlighted that the main use of A. araucana forests in the
whole history has been food provisioning. Animals and people have been eating its
pine nuts during 1000 years. Even introduced exotic animals as livestock (i.e. sheep,
cows, goats, horses) as well as feral animals (i.e. red deer, wild pigs) have been fed
on the species. In some forests, the tons of produced pine nuts feed the whole population of domestic and wild animals and constitute for some of them the main nourishment source of the whole system (Gallo et al. 2004b). Sometimes, the remaining
pine nuts for collection by the Mapuche communities are very scarce, since they
vary from year to year and are according to the different types of forests.
Consequently, a reasonable objective of a breeding programme for the species is
the pine nut production. There are trees in the natural forest that abundantly produce
cones and viable seeds almost every year. Their location is known by the usual collectors of pine nuts that belong to the Mapuche communities, and therefore, they
should be involved in the programme. Mass-selected trees can be propagated vegetatively by grafting on rootstocks of the same species in order to install clonal seed
orchards. This procedure is currently being conducted for Araucaria angustifolia in
the Manuel Belgrano Forest Station of INTA in the northeastern extreme of
Argentina (see Chap. 15). Such a breeding programme for the production of pine
nuts is being developed in Spain for Pinus pinea (Mutke Regneri et al. 2007).
Recently, several elite P. pinea clones and a clone mixture, selected for outstanding
P. Marchelli et al.