| Seed dispersal is one of the key processes that can greatly affect plant distribution and genetic structure. Dispersal mediated by different animals may have different influences on plant populations, while the process from seeds to adults have been recognized as a'black box'due to conventional approaches are often unable to illustrate the whole process. Thus, the study on seed dispersal has been the focus for ecological research for many years. In this study, we took ant-dispersed Globba lancangensis and bird-dispersed Ficus cyrtophylla as two study cases. By employing new-developed molecular markers, we aimed to understand how seed dispersal could shape plant spatial pattern and spatial genetic structure during population regeneration processes.G. lancangensis is a typical myrmecochorous perennial herb. Field observation on seed dispersal by ants found that four ant species were the main visitors and transporters of the seeds: Pheidole watsoni Forel., Pheidole capellini Emery., Pachycondyla luteipes Mayr. and Odontoponera transversa Smith. The mean dispersal distance was 0.47 m (Range = 0.01–3.35 m, N = 470). Ant exclusion was made to practically detect the effects of ant dispersal. As a result, we found that although ant dispersal could not significantly change the mean nearest neighbor distance, it obviously reduced the clustering degree of seedlings. For spatial genetic structure (SGS) analysis with ISSRs, the whole correlagram of all individuals from 2003 showed significant positive autocorrelations between genetic and geographical distances within 4 m, and presented a patchy structure in such patch size in the studied population. This pattern was likely associated with limited seed dispersal. The comparative analysis of fine-scale correlograms (within 4 m) for ant-excluded treatment indicated that lacking ants as the primary dispersers could have a similar pattern to ant dispersal presence, which is likely due to the restriction of ant dispersal distance. Ant-mediated dispersal contributed to reduce seedling clustering degree and plays a minor role in developing and maintaining the local SGS in G. lancangensis.F. cyrtophylla is a dioecious bird-dispersed fig tree species. The major dispersers were Pycnonotus jocosus, Pycnonotus melanicterus and Pycnonotus aurigaster. Seed collection by seed traps indicated F. cyrtophylla could produce fruits all-year round at population level, and a fruit-fall pink appeared from August to October. The seed deposition pattern was significantly nonrandom (Kolmogorov-Smimov test, P < 0.01). The amount of seeds collected from different traps was parabolically correlated to both leaf area index and light density above seed traps (r values were 0.429 and 0.362 respectively, N = 46), which may suggest seed traps under moderate light conditions tended to receive more seeds. The nonrandom seed fall might be associated with the behavior of frugivorous birds.Parentage analysis showed that gene dispersal of F. cyrtophylla could commonly occur both within and among populations. There were 51.9% of gene flow came from within-population with dispersal distance of 60.5 m (Range = 9.0–198.6 m, SE = 4.4, N = 69). The mean distance of seeds away from their mother trees was 1101.5 m (Range = 14.3–2713.6 m, SE = 262.6, N = 17) and 41.2% of the mother trees were within population (Mean dispersal distance = 45.9 m, range = 14.3–107.2 m, SE = 14.8, N = 7). The mean distance of seeds to their father trees was 1019.9 m (Range = 14.3–2677.3 m, SE = 194.1, N = 32), and 50% of the father trees were from within-population (Mean dispersal distance = 58.1 m, Range =14.3–104.1 m, SE = 8.1, N = 16). Both seeds and pollen could be dispersed to > 2 km and there were no significant difference between the dispersal distances of seeds and pollen, which indicated that both seed and pollen mediated gene flow provided equal contributions to the total gene flow of F. cyrtophylla.The mean gene flow distance of seedlings was 846.5 m (Range = 2.1–2725.9 m, SE = 78.2, N = 153), and 56.8% of the gene flow came from within-population (Mean dispersal distance = 104.1 m, range = 2.1–233.0 m, SE = 6.5, N = 88). The mean distance of seedlings to their mother trees was 603.3 m (Range = 10.6–2725.9 m, SE = 182.5, N = 29), and 75.9% of the mother trees located within population (Mean dispersal distance = 77.6 m, range = 10.6–107.0 m, SE = 11.1, N = 22). The mean distance of seedlings to their father trees was 1091.9 m (Range = 14.3–2677.3 m, SE = 169.7, N = 42), and 50% of the father trees came from within-population (Mean dispersal distance = 107.2 m, range = 20.8–210.7 m, SE = 12.4, N = 21). Within population, both seed flow and pollen flow were significantly different in dispersal distance to that in seed stage.In seedling correlagram, significant SGS was detected at short distance class (< 10 m). The whole pattern of seedling correlagram showed repeated positive to negative correlations to some extent, indicating seedlings were patch structured in this population. This may reflect the seed cluster resulting from seed dispersers'behavior although seed could be long and widely dispersed. The fine-scale SGS developed in seeds was to some extent kept to seedlings. Whereas to saplings or adults, no significant SGS was found, indicating the factors during population regeneration could obviously change or erase the initial template established by seeds or seedlings. Thus, gene flow is the determinant of initial SGS of seeds and seedlings, while local selection processes played critical roles for SGS development of saplings and adults.As a whole, the short-distance ant-mediated seed dispersal provided a significant minor role in developing and maintaining of local SGS. Frugivorous bird-mediated dispersal greatly enhanced gene flow both within and among populations, which played a critical role in shaping population genetic structure. The selection occurred in the processes from seedlings to adults also showed an obvious influence on SGS. Molecular tools may help people to indeed achieve a better understanding on the regeneration process, which was still recognized as a'black box'now, from seed dispersal to population establishment.
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