Transcript Adaptations of Salvia for insect pollination by bees
Adaptations of Salvia for insect pollination by bees
Pistil overhanging landing platform Stamens form “lever” Tubular shape, contains nectar Nectar guides Landing platform Bees attracted to blue and yellow flowers Lorraine Kuun, July 2011
• • • • • • • • Adaptations of flowers for bird pollination High yield of dilute nectar Bigger than most insect-pollinated flowers Open in daytime, often red Sturdy against rough feeding of birds Little or no scent – birds have poor sense of smell Protect ovary against beaks by being inferior or by partition Pollen sticks together in clumps Often erect or with landing platform for birds that do not hover Lorraine Kuun, July 2011
Adaptations of Strelitzia for pollination by birds
Stigma close to pollen Stamens fused in tube to fit beak Sturdy landing platform Nectaries Lorraine Kuun, July 2011 Bright colours
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
Adaptations for wind pollination
• • • • • • Flowers do not have scent, nectar or brightly coloured petals – no need to attract pollinators.
Flowers high on plant to be exposed to wind.
Flowers usually small and reduced, lacking calyx or corolla (sepals and petals).
Anthers large and well-exposed.
Masses of light, non-sticky pollen produced.
Stigmas long and feathery with large area for trapping pollen.
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
• The pollen grain germinates Meiosis occurs in the pollen grain.
• The male gametes haploid .
are • When the ripe pollen grain lands on a receptive stigma, it will germinate. • The pollen grain germinates and form a pollen tube.
Lorraine Kuun, July 2011
The germinated pollen grain is the male gametophyte Lorraine Kuun, July 2011
• • • The female pistil The ovary contains the ovule(s) with female gametes (n). The pollen tube grows down the style, through the micropyle and into the embryo sac.
Double fertilisation occurs.
Lorraine Kuun, July 2011
The female gametophyte: germ sac with 8 nuclei Lorraine Kuun, July 2011
Lorraine Kuun, July 2011