Edge effects enhance selfing and seed harvesting efforts in the insect-pollinated Neotropical tree Copaifera langsdorffii (Fabaceae)

Abstract

Edge effects may affect the mating system of tropical tree species and reduce the genetic diversity and variance effective size of collected seeds at the boundaries of forest fragments because of a reduction in the density of reproductive trees, neighbour size and changes in the behaviour of pollinators. Here, edge effects on the genetic diversity, mating system and pollen pool of the insect-pollinated Neotropical tree Copaifera langsdorffii were investigated using eight microsatellite loci. Open-pollinated seeds were collected from 17 seed trees within continuous savannah woodland (SW) and were compared with seeds from 11 seed trees at the edge of the savannah remnant. Seeds collected from the SW had significantly higher heterozygosity levels (H o ¼ 0.780; H e ¼ 0.831) than seeds from the edge (H o ¼ 0.702; H e ¼ 0.800). The multilocus outcrossing rate was significantly higher in the SW (t m ¼ 0.859) than in the edge (t m ¼ 0.759). Pollen pool differentiation was significant, however, it did not differ between the SW (F 00 ft ¼ 0.105) and the edge (F 00 ft ¼ 0.135). The variance effective size within the progenies was significantly higher in the SW (N e ¼ 2.65) than at the edge (N e ¼ 2.30). The number of seed trees to retain the reference variance effective size of 500 was 189 at the SW and 217 at the edge. Therefore, it is preferable that seed harvesting for conservation and environmental restoration strategies be conducted in the SW, where genetic diversity and variance effective size within progenies are higher.

Reproductive ecology ofOcotea catharinensis, an endangered tree species

“…Edge effect, for instance, enhanced selfing rates in individuals of Copaifera langsdorffi (Fabaceae; Tarazi et al . ).…”

“…Therefore, in addition to effective size effects, other factors, such as crown position in the forest stratum, distance to other reproducing individuals and position in the landscape, edge or core, may influence the estimated outcrossing rates. Edge effect, for instance, enhanced selfing rates in individuals of Copaifera langsdorffi (Fabaceae; Tarazi et al 2013).…”

Demographic history and spatial genetic structure in a remnant population of the subtropical tree Anadenanthera colubrina var. cebil (Griseb.) Altschul (Fabaceae)

“…cebil displays a mixed mating system. Selfing is common in legumes, and studies on the proportion of selfed vs. outcrossed offspring in other Neotropical legume trees have revealed mixed mating systems, for instance in Senna multijuga (Ribeiro and Lovato 2004), Copaifera langsdorfii (Tarazi et al 2013), and Dipteryx alata (Tambarussi et al 2017). More detailed investigation on the genetic constitution of offspring would be needed for a detailed characterization of the mating system of A. colubrina var.…”

Integrated pest management is the lucrative bridge connecting the ever emerging knowledge islands of genetics and ecology

“…In addition to spatial and temporal patterns described by Ni et al . () in this special section, other aspects of spatial ecology, for example, the edge effect and “sun effect” described in the forest ecosystems (Kautz et al ., ; Tarazi et al ., ) could also be examined in the agroecosystems. Each of the 4 manuscripts presented in this special section has demonstrated the value and synergism of comprehensively understanding genetics and ecology of both host crop plants and insect pests in developing innovative IPM strategies.…”

“…It is worth noting that the spatial and temporal pattern data described by Ni et al (2014c) were collected from the small maize fields that are approximately 0.4 hectares only, the patterns on a large scale should be further examined. In addition to spatial and temporal patterns described by Ni et al (2014c) in this special section, other aspects of spatial ecology, for example, the edge effect and "sun effect" described in the forest ecosystems (Kautz et al, 2013;Tarazi et al, 2013) could also be examined in the agroecosystems. Each of the 4 manuscripts presented in this special section has demonstrated the value and synergism of comprehensively understanding genetics and ecology of both host crop plants and insect pests in developing innovative IPM strategies.…”