334
between C. alliodora and C. trichotoma, as shown by the neighbor-joining tree of
Cordia into the Sebestena clade.
In the Cedrela case, both rainforests do not share the same species. For South
American Cedrela genus, the Amazonian Rainforest of Peru constitutes a center of
species diversity, although they are certainly not a center of old Cedrela diversity.
The ancestral habitat preference of Cedrela could be inferred by morphological
adaptations. Deciduous habit, shoot apices protected by a cluster of bud scales, and
capsular fruits with dry, winged, and wind-dispersed seeds of extended viability are
features that point to a long evolutionary history of Cedrela in dry forest habitats
(Muellner et al. 2010).
Natural hybridization between closely related forest tree species is a common
event in nature and has been documented in several economically important genera
(Zelener et al. 2016), such as Quercus (Whittemore and Schaal 1991), Eucalyptus
(Potts and Wiltshire 1997), Nothofagus (Stecconi et al. 2004), Prosopis (Vega and
Hernández 2005), and Populus (Di Fazio et al. 2011). Hybrid zones under forest
harvesting could impact in the wood trade somehow. In 2007, the company GMF
Latino Americana was harvesting mainly Cedrela balansae in a management unit of
the natural forest in Northwest of the Province of Salta. Surprisingly, C. balansae’s
wood from this area was rejected on the domestic market. The genetic relationships
between individuals was determined through molecular markers (AFLP and ITS),
recognizing the presence of individuals with ancestry of both C. balansae and
C. saltensis. This result uncovered strong support for the occurrence of natural
hybridization between both Cedrela species. Additionally, hybrid zones were identified in areas of sympatry (at both the Calilegua National Park and the San Andrés
farm) and in transition zones from 820 to 1100 m asl (localities of Pintascayo and
Acambuco). That is an interesting case, because the researchers do not usually put
the results of their work into practice, even when the primary purpose of their
research is the preservation of biodiversity (Gallo et al. 2009).
Likewise, evidence could not be found of hybridization with C. angustifolia,
neither of C. balansae nor of C. saltensis (Zelener et al. 2016). Although Cedrela
wood from hybrid areas is not desirable in the domestic market, from an evolutionary point of view, these hybrid zones may be important due to their potential adaptive value to the new climatic scenarios (see Chap. 13). The correct characterization
of Cedrela’s germplasm has direct implications for enrichment and restoration plans
(specific purity) and the implementation of appropriate conservation strategies and
genetic improvement.
Muellner (2010) places Cedrela balansae (one of the cedars from the Yungas)
and C. fissilis (the cedar from the Alto Paraná Rainforest) phylogenetically very
close, although geographically separated, which would imply a greater affinity for
hybridization and a risk of genetic contamination in the event of seed or seedlings
transfers. However, this factor is not sufficient since a phenological synchrony is
required in the flowering and action of pollinators. Cedrela fissilis has been used for
enrichment of degraded forests in the Southern sector of the Yungas, whose latitude
coincides with the Alto Paraná Rainforest, but so far no evidence of entities of the
genus Cedrela was found as invasive forms (Trapani, personal communication).
L. F. Fornes
between C. alliodora and C. trichotoma, as shown by the neighbor-joining tree of
Cordia into the Sebestena clade.
In the Cedrela case, both rainforests do not share the same species. For South
American Cedrela genus, the Amazonian Rainforest of Peru constitutes a center of
species diversity, although they are certainly not a center of old Cedrela diversity.
The ancestral habitat preference of Cedrela could be inferred by morphological
adaptations. Deciduous habit, shoot apices protected by a cluster of bud scales, and
capsular fruits with dry, winged, and wind-dispersed seeds of extended viability are
features that point to a long evolutionary history of Cedrela in dry forest habitats
(Muellner et al. 2010).
Natural hybridization between closely related forest tree species is a common
event in nature and has been documented in several economically important genera
(Zelener et al. 2016), such as Quercus (Whittemore and Schaal 1991), Eucalyptus
(Potts and Wiltshire 1997), Nothofagus (Stecconi et al. 2004), Prosopis (Vega and
Hernández 2005), and Populus (Di Fazio et al. 2011). Hybrid zones under forest
harvesting could impact in the wood trade somehow. In 2007, the company GMF
Latino Americana was harvesting mainly Cedrela balansae in a management unit of
the natural forest in Northwest of the Province of Salta. Surprisingly, C. balansae’s
wood from this area was rejected on the domestic market. The genetic relationships
between individuals was determined through molecular markers (AFLP and ITS),
recognizing the presence of individuals with ancestry of both C. balansae and
C. saltensis. This result uncovered strong support for the occurrence of natural
hybridization between both Cedrela species. Additionally, hybrid zones were identified in areas of sympatry (at both the Calilegua National Park and the San Andrés
farm) and in transition zones from 820 to 1100 m asl (localities of Pintascayo and
Acambuco). That is an interesting case, because the researchers do not usually put
the results of their work into practice, even when the primary purpose of their
research is the preservation of biodiversity (Gallo et al. 2009).
Likewise, evidence could not be found of hybridization with C. angustifolia,
neither of C. balansae nor of C. saltensis (Zelener et al. 2016). Although Cedrela
wood from hybrid areas is not desirable in the domestic market, from an evolutionary point of view, these hybrid zones may be important due to their potential adaptive value to the new climatic scenarios (see Chap. 13). The correct characterization
of Cedrela’s germplasm has direct implications for enrichment and restoration plans
(specific purity) and the implementation of appropriate conservation strategies and
genetic improvement.
Muellner (2010) places Cedrela balansae (one of the cedars from the Yungas)
and C. fissilis (the cedar from the Alto Paraná Rainforest) phylogenetically very
close, although geographically separated, which would imply a greater affinity for
hybridization and a risk of genetic contamination in the event of seed or seedlings
transfers. However, this factor is not sufficient since a phenological synchrony is
required in the flowering and action of pollinators. Cedrela fissilis has been used for
enrichment of degraded forests in the Southern sector of the Yungas, whose latitude
coincides with the Alto Paraná Rainforest, but so far no evidence of entities of the
genus Cedrela was found as invasive forms (Trapani, personal communication).
L. F. Fornes