Chapter 2 The relationship between seed size and the pollen - ovule ratio – a comparative test of sex allocation theory
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چکیده
Hypothesis: Sex allocation theory predicts that the pollen-ovule ratio should increase linearly with increasing seed size among seed plants (Charnov 1982). Data examined: We retrieved data for pollen-ovule ratio, seed size and possible confounding variables (ovule number, plant height, mating system) from a database and additional literature for 299 angyosperm plant species of the German flora. Methods: We analyzed uncorrected cross species data as well as phylogenetically independent contrasts (PIC) with model II regressions and (partial) correlations. Results: A linear positive correlation between pollen-ovule ratio and seed size exists across all plant species analyzed and within different mating systems for phylogenetically corrected and uncorrected data. This positive correlation remained valid when we controlled for the effect of possible confounding variables. Conclusions: The interspecific variation of the pollen-ovule ratio depends – at least partly – on the allocation of resources to female sexual function.
منابع مشابه
The relationship between the pollen–ovule ratio and seed size: a comparative test of a sex allocation hypothesis
Hypothesis: Sex allocation theory predicts that the pollen–ovule ratio should increase linearly with increasing seed size among seed plants (Charnov, 1982). Data examined: We retrieved data for the pollen–ovule ratio, seed size, and possible confounding variables (ovule number, plant height, mating system) from a database and additional literature for 299 gymnosperm plant species of the German ...
متن کاملThe relationship between the pollen–ovule ratio and pollen size: another comparative test of a sex allocation hypothesis
Hypothesis: Sex allocation theory predicts that the pollen–ovule ratio should decrease linearly with increasing pollen size among seed plants (Charnov, 1982). Data examined: We retrieved data for pollen–ovule ratio, pollen size, pollen grain number, and mating system from published literature for 311 angiosperm plant species. Methods: We used model II regressions on cross-species data as well a...
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