106
Fortunately, roble pellín seeds are orthodox, and therefore their viability can be
maintained at 4 °C for several years if they are stocked at a humidity lower than
10% (Escobar and Donoso 1996). Thus, mast years should be considered for collecting and stocking seeds.
4.5 First Steps Towards Breeding of Roble pellín
in Argentina
The oldest provenance trials of N. obliqua were installed in Britain in 1979 and in
1981 but almost exclusively with Chilean provenances and local seed sources
(Mason et al. 2018). Only one Argentinean provenance (Lake Lácar basin) was
assayed and only in the two trials of 1981. This provenance resulted in the best in
comparison with two provenances from Chile (100% survival and 6.1 m tall at
10 years in Yorkshire; 99% survival and 7.7 m tall at 13 years in Scotland).
Meanwhile, in Argentina breeding of roble pellín has begun in the 2000s, with the
first field trials installed in 2004. That year, INTA established a provenance trial in
Lanín National Park (40° 07′ 48′‘S, 71° 28′ 48″ W, 920 m asl) representing ten
Argentinean natural populations. The average survival four years later was 91%,
with a mean height of 115.82 cm ±42.26 cm. Differences in trunk height were found
among populations: one population from the north (Lake Quillén basin) included
the tallest individuals, and the northernmost population of Argentina (Epulauquen)
had the shortest ones (Azpilicueta et al. 2014), which is consistent with the greenhouse and field trials performed by Barbero (2014).
The distinct character of Epulauquen population has repeatedly been shown,
both through genetic markers as through variation in quantitative traits. This distinctness is relevant for breeding since it is likely to be caused by adaptation to cold
and/or high altitude environments (this population is located at 1500 m asl), which
have an effect similar to that of drought (e.g. Yang et al. 2010). Thus, Epulauquen
could be a key provenance for the cultivation of the species in harsh sites characterised by drought or out-of-season frosts. Based on these considerations, a Progeny
Seed Orchard composed by 20 open-pollinated families exclusively of Epulauquen
population was installed in the Trevelin Forest Station of INTA in 2004 (N = 480).
In a first evaluation at 7 years of age (data not published), the mean height of this
seed orchard was 199 ± 63 cm, with a survival of 96%. Differences among families
were shown at this early stage, so further genetic evaluations will allow selecting the
best genotypes and subsequently thinning the trial to finally turn it into an improved
Progeny Seed Orchard. At the light of this preliminary results, a new progeny trial
exclusively of the Epulauquen provenance has been installed in 2013, this time with
25 open-pollinated families (N = 600) and located in a property of CORFONE, the
most important plantation company of Argentine Patagonia, near San Martín de los
Andes (40° 4′ 57″ S; 71°20′26″ W; 1125 m asl). At the age of three years, with a
M. M. Azpilicueta et al.
Fortunately, roble pellín seeds are orthodox, and therefore their viability can be
maintained at 4 °C for several years if they are stocked at a humidity lower than
10% (Escobar and Donoso 1996). Thus, mast years should be considered for collecting and stocking seeds.
4.5 First Steps Towards Breeding of Roble pellín
in Argentina
The oldest provenance trials of N. obliqua were installed in Britain in 1979 and in
1981 but almost exclusively with Chilean provenances and local seed sources
(Mason et al. 2018). Only one Argentinean provenance (Lake Lácar basin) was
assayed and only in the two trials of 1981. This provenance resulted in the best in
comparison with two provenances from Chile (100% survival and 6.1 m tall at
10 years in Yorkshire; 99% survival and 7.7 m tall at 13 years in Scotland).
Meanwhile, in Argentina breeding of roble pellín has begun in the 2000s, with the
first field trials installed in 2004. That year, INTA established a provenance trial in
Lanín National Park (40° 07′ 48′‘S, 71° 28′ 48″ W, 920 m asl) representing ten
Argentinean natural populations. The average survival four years later was 91%,
with a mean height of 115.82 cm ±42.26 cm. Differences in trunk height were found
among populations: one population from the north (Lake Quillén basin) included
the tallest individuals, and the northernmost population of Argentina (Epulauquen)
had the shortest ones (Azpilicueta et al. 2014), which is consistent with the greenhouse and field trials performed by Barbero (2014).
The distinct character of Epulauquen population has repeatedly been shown,
both through genetic markers as through variation in quantitative traits. This distinctness is relevant for breeding since it is likely to be caused by adaptation to cold
and/or high altitude environments (this population is located at 1500 m asl), which
have an effect similar to that of drought (e.g. Yang et al. 2010). Thus, Epulauquen
could be a key provenance for the cultivation of the species in harsh sites characterised by drought or out-of-season frosts. Based on these considerations, a Progeny
Seed Orchard composed by 20 open-pollinated families exclusively of Epulauquen
population was installed in the Trevelin Forest Station of INTA in 2004 (N = 480).
In a first evaluation at 7 years of age (data not published), the mean height of this
seed orchard was 199 ± 63 cm, with a survival of 96%. Differences among families
were shown at this early stage, so further genetic evaluations will allow selecting the
best genotypes and subsequently thinning the trial to finally turn it into an improved
Progeny Seed Orchard. At the light of this preliminary results, a new progeny trial
exclusively of the Epulauquen provenance has been installed in 2013, this time with
25 open-pollinated families (N = 600) and located in a property of CORFONE, the
most important plantation company of Argentine Patagonia, near San Martín de los
Andes (40° 4′ 57″ S; 71°20′26″ W; 1125 m asl). At the age of three years, with a
M. M. Azpilicueta et al.