350
Most of the genetic variation (87%) was observed within populations (AMOVA;
GenAlEx 6.2, Peakall and Smouse 2006), as expected for long-lived, woody, and
outcrossing species (Hamrick et al. 1992; Nybom 2004). In addition, a moderate
genetic differentiation among populations (Φ PT = 0.130, F ST = 0.115) was found.
Taking into account the extent of population distribution and the features of latitudinal sectors described for the Yungas (Brown et al. 2001), gene flow restriction
associated with spatial isolation of sampled populations (~600 km) was suggested.
The discontinuous orography of the Yungas and habitat disturbance caused by logging modified pollination patterns, which would also increase the genetic structure
(Aizen and Feinsinger 2002).
13.2.1.2 Genetic Variation and Latitude
A combined data analysis showed a close relationship between the genetic variability patterns of C. angustifolia in the Yungas of NWA and the latitude (Table 13.2,
Fig. 13.2). Intrapopulation genetic diversity (He, PPL) tested against latitude was
significant and showed a clear decrease with increasing latitude (InfoStat 2008,
Fig. 13.2a). In addition, genetic structure was in strong agreement with latitudinal
sectors of the Yungas (Brown et al. 2001). Three genetic clusters (best K value
according to Evanno et al. 2005 was K = 3) were identified by Bayesian modeling
(Structure 2.2.3, Pritchard et al. 2000, Fig. 13.2b), and three UPGMA dendrogram’
groups (NTSYS 2.0, Rohlf 1998; data shown in Inza et al. 2012) were in correspondence with northern, central, and southern Yungas. Additionally, diversity (He, PPL,
and EB) was estimated for each latitudinal sector, and, as proposed by Brown et al.
(2001, 2006), populations were grouped into northern, central, and southern subregions of Yungas (Table 13.2). To minimize the effect of disturbance, only populations with some disturbance level (LDP and DP) were compared.
In agreement with the latitudinal pattern of biological diversity of the Yungas
(Brown et al. 2001; Juárez et al. 2007), the highest genetic diversity was detected in
the north (He, 0.181; PPL, 89.3%; and EB, 68), decreasing towards the south (He,
0.093; PPL, 38.6%; and EB, 11; Inza et al. 2012). When only undisturbed populations were compared, genetic diversity of Baritú National Park in the north was
higher than La Florida Provincial Park in the south (Table 13.2). A significant
genetic differentiation among latitudinal sectors (Φ RT = 0.07, p = 0.001) and undisturbed populations of Baritú National Park and La Florida Provincial Park
(Φ PT = 0.10, p = 0.001) support these results (AMOVA, GenAlEx 6.2, Peakall and
Smouse 2006). Furthermore, the association of genetic diversity with latitude,
which was calculated for each disturbance group (InfoStat 2008), was high, negative, and significant (Fig. 13.2a).
Latitudinal patterns of biological diversity in the Yungas have been explained by
less benign climate towards the southern region (Brown et al. 2001, 2006; Juárez
et al. 2007). We hypothesize that the warmth-prone habit of C. angustifolia (Villalba
et al. 1992) may have led to larger populations and greater persistence of genetic
variability in northern Yungas. In long-term periods, according to the climatic
N. Zelener et al.
Most of the genetic variation (87%) was observed within populations (AMOVA;
GenAlEx 6.2, Peakall and Smouse 2006), as expected for long-lived, woody, and
outcrossing species (Hamrick et al. 1992; Nybom 2004). In addition, a moderate
genetic differentiation among populations (Φ PT = 0.130, F ST = 0.115) was found.
Taking into account the extent of population distribution and the features of latitudinal sectors described for the Yungas (Brown et al. 2001), gene flow restriction
associated with spatial isolation of sampled populations (~600 km) was suggested.
The discontinuous orography of the Yungas and habitat disturbance caused by logging modified pollination patterns, which would also increase the genetic structure
(Aizen and Feinsinger 2002).
13.2.1.2 Genetic Variation and Latitude
A combined data analysis showed a close relationship between the genetic variability patterns of C. angustifolia in the Yungas of NWA and the latitude (Table 13.2,
Fig. 13.2). Intrapopulation genetic diversity (He, PPL) tested against latitude was
significant and showed a clear decrease with increasing latitude (InfoStat 2008,
Fig. 13.2a). In addition, genetic structure was in strong agreement with latitudinal
sectors of the Yungas (Brown et al. 2001). Three genetic clusters (best K value
according to Evanno et al. 2005 was K = 3) were identified by Bayesian modeling
(Structure 2.2.3, Pritchard et al. 2000, Fig. 13.2b), and three UPGMA dendrogram’
groups (NTSYS 2.0, Rohlf 1998; data shown in Inza et al. 2012) were in correspondence with northern, central, and southern Yungas. Additionally, diversity (He, PPL,
and EB) was estimated for each latitudinal sector, and, as proposed by Brown et al.
(2001, 2006), populations were grouped into northern, central, and southern subregions of Yungas (Table 13.2). To minimize the effect of disturbance, only populations with some disturbance level (LDP and DP) were compared.
In agreement with the latitudinal pattern of biological diversity of the Yungas
(Brown et al. 2001; Juárez et al. 2007), the highest genetic diversity was detected in
the north (He, 0.181; PPL, 89.3%; and EB, 68), decreasing towards the south (He,
0.093; PPL, 38.6%; and EB, 11; Inza et al. 2012). When only undisturbed populations were compared, genetic diversity of Baritú National Park in the north was
higher than La Florida Provincial Park in the south (Table 13.2). A significant
genetic differentiation among latitudinal sectors (Φ RT = 0.07, p = 0.001) and undisturbed populations of Baritú National Park and La Florida Provincial Park
(Φ PT = 0.10, p = 0.001) support these results (AMOVA, GenAlEx 6.2, Peakall and
Smouse 2006). Furthermore, the association of genetic diversity with latitude,
which was calculated for each disturbance group (InfoStat 2008), was high, negative, and significant (Fig. 13.2a).
Latitudinal patterns of biological diversity in the Yungas have been explained by
less benign climate towards the southern region (Brown et al. 2001, 2006; Juárez
et al. 2007). We hypothesize that the warmth-prone habit of C. angustifolia (Villalba
et al. 1992) may have led to larger populations and greater persistence of genetic
variability in northern Yungas. In long-term periods, according to the climatic
N. Zelener et al.