Understanding local patterns of genetic diversity in dipterocarps using a multi-site, multi-species approach: Implications for forest management and restoration

Abstract

The lowland tropical forests of Southeast Asia are dominated by a single family of canopy and emergent trees, the Dipterocarpaceae. The seeds of dipterocarps are gravity or gyration dispersed. Short distance and limited seed dispersal via these mechanisms result in the aggregation of related individuals and strong fine-scale spatial genetic structure (FSGS). In logged and fragmented forests, where gene flow may be disrupted, tree species with strong FSGS are predicted to exhibit increased inbreeding,

Isolation of microsatellite loci in the African tree species Staudtia kamerunensis (Myristicaceae) using high-throughput sequencing

“…This knowledge however, is crucial for the adequate management of both natural stands and plantation forests, and to assess sustainable logging practices [1]. The intra-specific diversity and mating system determine how S. kamerunensis will cope with the increasing habitat fragmentation in tropical Africa, caused by either conversion or logging [2]. For example, species that are self-incompatible and therefore almost exclusively outcrossed, might be more vulnerable to reproductive isolation than selfing species [2].…”

“…The intra-specific diversity and mating system determine how S. kamerunensis will cope with the increasing habitat fragmentation in tropical Africa, caused by either conversion or logging [2]. For example, species that are self-incompatible and therefore almost exclusively outcrossed, might be more vulnerable to reproductive isolation than selfing species [2]. Also, the application of suitable DNA markers in future breeding programmes of S. kamerunensis would help with the assessment of coancestry and the selection of superior parent trees to reduce the problems of inbreeding [3].…”

Do large-seeded herbs have a small range size? The seed mass-distribution range trade-off hypothesis

“…On the other hand, species with poor dispersal capacity get adapted to local conditions more rapidly and thus speciate rapidly , which also results in smaller range sizes (Lester et al, 2007;Thompson et al, 1999). However, direct quantification of dispersal ability can be very difficult (Jacobson & Peres-Neto, 2010); thus, different proxies are often used instead of a direct measure of it (Stewart et al, 1998;Tito de Morais et al, 2015). One of these proxies is seed size which is considered to be related to dispersal ability (Fenner & Thompson, 2005;Guo et al, 2000;Tremlová & Münzbergová, 2007), mostly due to the numerosity of small seeds (seed size/number trade-off, Leishman, 2001) and the apparently obvious assumption that smaller seeds are more easily transported by wind and also by other agents (Greene & Johnson, 1993;Venable & Brown, 1988).…”

Exploring the role of genetic diversity and relatedness in tree seedling growth and mortality: A multispecies study in a Bornean rainforest

“…Seedlings were genotyped with 10 primers for S. gibbosa (Kettle, Hollingsworth, et al, ; Lee, Tani, Ng, & Tsumura, ; Tito de Morais et al, ), seven primers for S. argentifolia (Lee et al, ; Ujino et al, ), 10 primers for S. acuminatissima (Kettle, Hollingsworth, et al, ; Lee et al, ; Tito de Morais et al, ) and six primers for P. tomentella (Kettle, Hollingsworth, et al, ; Lee et al, ; Ng et al, ). Fragmentation analysis was carried out on an ABI 3730 capillary sequencer (Applied Biosystems; see Table and Tito de Morais et al, for more details). These data were used to calculate summary statistics at the species level: number of alleles (Na), observed heterozygosity (Ho) and expected heterozygosity (He) using Genalex 6.4 (Peakall & Smouse, ) and allelic richness (Ae) and inbreeding coefficient (Fis) with FSTAT 2.9.3.2 (Goudet, ).…”

“…To test this prediction, we conducted field experiments in undisturbed forest and collected 30 months of growth and mortality data from 1,485 genotyped seedlings from four dipterocarp species. We selected the species based on seed and flower traits, reflecting differential patterns of gene flow, and all being medium wood density as a surrogate of the species' regeneration strategy (Table ) based on the observation that low wood density species are light‐demanding and fast‐growing, while heavier hardwoods are shade‐tolerant and slower growing (following Tito de Morais et al, ). We explore the following specific hypotheses: Probability of seedling mortality declines with increasing individual multilocus heterozygosity. Relative growth rates increase with increasing individual multilocus heterozygosity. Seedlings surrounded by related conspecifics (cousin, half‐sibs or full‐sibs) have higher probability of mortality than a seedling surrounded by unrelated seedlings. Seedlings surrounded by related conspecifics grow more slowly than seedlings surrounded by unrelated conspecifics. …”