67
with some significant exceptions (being bud burst phenology the main of them, as
mentioned above). This pattern matches with the restricted distribution area of the
species in Argentina and especially with its lack of large environmental ranges. In
this regard, some phenological traits were found to be correlated with altitude and
mean July temperature of the provenances, but no trait was correlated with mean
annual precipitation or UNEP aridity index. The low genetic variation found within
populations means a worrisome risk with respect to the global climate change, since
the species might be not capable to adapt, and its local persistence could depend
exclusively on phenotypic plasticity.
3.4 The Underground Diversity: Relevance of Mycorrhizas
and Other Soil Fungi Associated to Raulí
In temperate and boreal forests, the establishment and growth of different forestry
species that occupy large areas worldwide are usually dependent on the mycorrhizas
present in their roots. Mycorrhizas are a symbiotic association between plants and
soil fungi that usually benefit host plants by enhancing water and nutrient uptake, in
addition to increasing host resistance to pathogens and other biotic and abiotic
stresses. Consequently, mycorrhizas have a direct bearing on plant community
structure and productivity (Smith and Read 2008). All Nothofagus species are
extensively colonized by ectomycorrhizas (EcM), thus suggesting a strong dependence on this symbiosis (Diehl et al. 2008; Fernández et al. 2013, 2015). Given the
key role of EcM in raulí’s life cycle, it is important to consider this symbiosis to
describe the ecology of the species but also to ponder its inclusion in nursery technology during seedling production.
3.4.1 Intraspecific Variation of Ectomycorrhizal Fungal
Communities in Raulí
In Argentina, N. alpina is not commonly inoculated with EcM fungi during its cultivation in nurseries, in spite of the deep impact that this practice can presumably
have on the industrial seedling production. In order to analyse the mycorrhizal status of raulí seedlings produced under standard local protocols, a 2-year experiment
was carried out (Fernández et al. 2013). Seedlings were produced in containers with
ferti-irrigation according to the procedures adjusted for Nothofagus species
(Schinelli Casares 2013). When seedlings were 1-year-old, half of them were outplanted to the nursery soil (outside the greenhouse). After the rustification stage
(nutrient supply and irrigation frequency were significantly reduced), between 6
and 12 months after germination, the containerized seedlings in the greenhouse
were naturally colonized by EcM fungi present in the cultivation system. Meanwhile,
3 Raulí (Nothofagus alpina = N. nervosa): The Best Quality Hardwood in Patagonia
with some significant exceptions (being bud burst phenology the main of them, as
mentioned above). This pattern matches with the restricted distribution area of the
species in Argentina and especially with its lack of large environmental ranges. In
this regard, some phenological traits were found to be correlated with altitude and
mean July temperature of the provenances, but no trait was correlated with mean
annual precipitation or UNEP aridity index. The low genetic variation found within
populations means a worrisome risk with respect to the global climate change, since
the species might be not capable to adapt, and its local persistence could depend
exclusively on phenotypic plasticity.
3.4 The Underground Diversity: Relevance of Mycorrhizas
and Other Soil Fungi Associated to Raulí
In temperate and boreal forests, the establishment and growth of different forestry
species that occupy large areas worldwide are usually dependent on the mycorrhizas
present in their roots. Mycorrhizas are a symbiotic association between plants and
soil fungi that usually benefit host plants by enhancing water and nutrient uptake, in
addition to increasing host resistance to pathogens and other biotic and abiotic
stresses. Consequently, mycorrhizas have a direct bearing on plant community
structure and productivity (Smith and Read 2008). All Nothofagus species are
extensively colonized by ectomycorrhizas (EcM), thus suggesting a strong dependence on this symbiosis (Diehl et al. 2008; Fernández et al. 2013, 2015). Given the
key role of EcM in raulí’s life cycle, it is important to consider this symbiosis to
describe the ecology of the species but also to ponder its inclusion in nursery technology during seedling production.
3.4.1 Intraspecific Variation of Ectomycorrhizal Fungal
Communities in Raulí
In Argentina, N. alpina is not commonly inoculated with EcM fungi during its cultivation in nurseries, in spite of the deep impact that this practice can presumably
have on the industrial seedling production. In order to analyse the mycorrhizal status of raulí seedlings produced under standard local protocols, a 2-year experiment
was carried out (Fernández et al. 2013). Seedlings were produced in containers with
ferti-irrigation according to the procedures adjusted for Nothofagus species
(Schinelli Casares 2013). When seedlings were 1-year-old, half of them were outplanted to the nursery soil (outside the greenhouse). After the rustification stage
(nutrient supply and irrigation frequency were significantly reduced), between 6
and 12 months after germination, the containerized seedlings in the greenhouse
were naturally colonized by EcM fungi present in the cultivation system. Meanwhile,
3 Raulí (Nothofagus alpina = N. nervosa): The Best Quality Hardwood in Patagonia