Flower characteristics and breeding system of two phenological ecotypes of Cyclamen persicum Mill. (Myrsinaceae) in Israel
2008
Schwartz-Tzachor, R. | Eisikowitch, D. | Dafni, Amots
Cyclamen persicum Mill. in Israel consists of two discrete population types that differ in their flowering (fall versus winter) as well as leafing (hysteranthous versus synanthous) phenology. The two populations have similar pollen:ovule ratios, index of self incompatibility, stigma receptivity duration, pollen longevity, flower longevity, floral morphology and seed production rate. These data indicate no apparent selective pressure on floral characteristics or on the breeding system, which may be exerted by the pollinators. The two populations retained their autonomous blooming rhythm even after transplantation, which indicated that this character was genetically determined. There are no genetic barriers and the populations may share some pollinators (Schwartz-Tzachor et al. 2006). Thus the main potential restriction on gene flow is the incomplete phenological barrier. These findings may indirectly support our hypothesis that the phenological shift is due to environmental cues. Thus it was concluded that these two types are 'phenological ecotypes' in the sense of Turesson (1922) due to the unequivocal delineation of both types, as revealed by the timing of leaf appearance (synanthous versus hysteranthous) without any evidence of any intermediates.
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