Ovule dimorphism in Ficus asperifolia Miquel

It is now known that in Ficus the variability in the form of the style ensures that not all female flowers are oviposited by pollinating fig wasps. In monoecious species (e.g. F. ottoniifolia), initially the ovules and ovaries are all identical. Due to gradual differences in style length, style thickness, and form of the stigma not all flowers have the same chance on oviposition, and after wasp activity the flowers either develop wasps or seeds (Verkerke 1986). In contrast to this, the gynodioecious F. asperifolia is supplied with two specialized types of figs, viz., seed figs and gall figs. Seed figs contain female flowers that develop seeds (seed flowers); gall figs contain both male flowers and female flowers (gall flowers); in the latter the fig wasps develop. Seed flowers and gall flowers exhibit pronounced differences in the form of the style (Verkerke, in preparation). Next to this, the ovules of seed flowers and gall flowers are different from the start, and the term ovule dimorphism is introduced to describe this situation. In seed flowers (figs. la, 2a-b) the inner integument is initiated as a ringshaped primordium, while the outer one appears as a half ring at the antiraphal side. The mature ovules are provided with an inner integument circumvallating the nucellus, while the outer integument invests the antiraphal side and fuses with the raphe. This is the common situation in anatropous and hemianatropous ovules (Bouman 1984).