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We released seeds of two sympatric tree species, Corylus mandshurica (seed with thinner seed hull, higher nutrition) and C. heterophylla (seeds with thicker seed hull, lower nutrition) in the masting year of C. mandshurica in 2008, and C. heterophylla in 2009, respectively, to investigate how seed masting of the two sympatric Corylus species affects seed removal and dispersal fitness of the two species differently at both intra- and inter-specific levels.
At intra-specific level, the authors found mast seeding of both C. mandshurica and C. heterophylla significantly reduced seed removal, seed consumption, but increased seed dispersal distance and seed dispersal fitness of
the released seeds. Mast seeding of C. mandshurica increased seed caching of C. mandshurica. At inter-specific level, the authors found mast seeding of C. mandshurica reduced seed removal of C. heterophylla, but mast seeding of C. heterophylla did not significantly reduce seed removal of C. mandshurica. Mast seeding of C. mandshurica reduced seed consumption of C. heterophylla, while mast seeding of C. heterophylla reduced seed consumption of C. mandshurica. We found mast seeding of C. mandshurica significantly reduced seed dispersal distance of C. heterophylla, while mast seeding of C. heterophylla significantly increased seed dispersal distance of C. mandshurica. We found that mast seeding of C. mandshurica significantly increased seed dispersal fitness of C. heterophylla, while mast seeding of C. heterophylla did not significantly increase seed dispersal fitness of C. mandshurica. More studies are needed to reveal the ecological consequences of mast seeding at inter-specific or community-level. Seed
traits may attribute the differences of mast seeding at inter-specific level. Because seeds with thinner seed hull and higher
nutrition were more harvested and eaten by rodents, mast seeding of C. mandshurica might have reduced seed removal and seed consumption, but increased dispersal fitness of C. heterophylla (seeds with thicker seed hull, lower nutrition). Therefore, synchrony among species is, or is not, selectively beneficial
to the focus species depends on seed traits which determine gains from mast seeding at inter-specific level. 相似文献
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T Tobe S Minoshima S Yamase N H Choi M Tomita N Shimizu 《Cytogenetics and cell genetics》1991,57(4):193-195
SP-40,40 is a serum glycoprotein consisting of two different subunits (alpha and beta) assembled into a dimer by disulfide bonds. Northern blot hybridization, using total RNA from several cell lines, showed that SP-40,40 is expressed in glioblastoma and testicular tumor cells, as well as hepatoma cells. Spot blot hybridization of flow-sorted human chromosomes, using a SP-40,40 cDNA fragment as a probe, localized the gene for SP-40,40 to human chromosome 8. This gene has been given the designation CLI, for complement lysis inhibitor, by the Human Gene Nomenclature Committee. 相似文献