Материал из Антэкология /// Anthecology
The Variability of Organs Differentially Involved in Pollination, and Correlations of Traits in Genisteae (Leguminosae: Papilionoideae)
Annals of Botany, 2001. V. 88. No. 6. P. 1027–1037 (11).
Size differences in organs involved to varying degrees in pollen exchange (standard and keel petals, calyx, pedicel and inflorescence stem diameter), together with correlations among these traits, were investigated at both the intraspecific and interspecific levels in populations of 15 southern Spanish species of the papilionoid legume tribe Genisteae. Characteristics less related to pollination (e.g. pedicel length and stem diameter) were roughly twice as variable between individuals as petal or calyx dimensions. The coefficients of variation were in the range 16–19% vs . 7–10%, respectively. Standard and keel petal size varied in parallel, not only in conspecific individuals but also across species and genera, suggesting a tight developmental relationship between these organs and a low potential for evolutionary modification. The remaining characteristics covaried in different ways within and between species and thus appeared much less mutually constrained (particularly so for calyx size). Multivariate analyses of variance revealed significant population divergence in five out of six species. Overall, 28% of all variation in flower size occurred among populations and 72% within populations, but the proportion of variance accounted for by population membership varied extensively across species (from 1 to 64%) and was highest in two selfing annuals ( Lupinus ). Outcrossing perennials may show either high ( Stauracanthus, Genista ) or low ( Cytisus ) population differentiation. In addition to contributing to the increasing amount of data on quantitative floral variation in plants, results of this study may help understand how pleiotropic effects limit the evolutionary modification of some flower traits more than others in diverse plant groups.