Pollination ecology of three ecologically valuable carpetweed herbs, Mollugo cerviana, M. nudicaulis and M. pentaphylla (Molluginaceae)

摘要

Mollugo cerviana, M. nudicaulis and M. pentaphylla are annual herbs which usually grow in open dry sandy and sandy/loamy soils, and also occur in moist habitats, especially cultivated lands. The flowers possess five tepals, functional stamens and 3-carpelled ovary with several ovules and three stigmas. M. nudicaulis and M. pentaphylla are pollinated by insects. Haplothrips uses the flowers for breeding and feeding, which affects pollination. These species have specialized floral structural and functional behaviours for self-induced and spontaneous autogamy while keeping the options open for insect pollination after anthesis. They are facultative autogamous, which is reflected in pollen-ovule ratios and natural fruit and seed set rates. Seed dispersal modes include anemochory, ombrohydrochory and hydrochory. The seeds germinate immediately after their dispersal, and soil moisture is important in rupturing the seed coat. These species are best adapted to survive in open dry habitats as they take advantage of any sign of temporary humidity to complete their life cycle quickly.