Pollination

1. Pollination

2. The process of transferring the pollen grains from the male part of the flower to the female part is known as pollination. • Pollination must occur before fertilisation can occur

3. Types of pollination • Self pollination • Pollen grains falling on the stigma of the same flower or of a different flower but of the same plant

4. Adaptions to Self pollination • Homogamy : Maturation of androecium and Gynoecium at same time • Cliestogamy: Flowers never open before pollination

5. Cross pollination • Pollen from the anther of one plant is transferred to the the stigma of a different plant

6. Types of cross pollination • Hydrophily : pollination by water • anthers break off and float to surface releasing pollen that sinks to the female flowers that grow under the water

7. VallisneraEgeriadensa Female flowers float on surface and male flowers break off at surface (great fish food) and float to female. Once pollinated long peduncles recoil pulling flowers underwater to form fruits

8. Anemophily • Pollination by wind

10. Maize

11. Wind Pollinated Flowers

12. Entemophily • Pollination by insects

13. May have nectar guides: patterns of lines or dots that can guide bee to reward

14. Insect Pollinated Flowers

16. Euphorbia pulcherrima  Bracts are the flower petals of the plant. In fact, the flowers are grouped within the small yellow structures found in the center of each leaf bunch, and they are called cyathia.

17. Calotropis procera It shows translator or clip mechanism. Pollen grains are present in pollinia. The pollinia are attached to a rough and sticky disc called corpusculum. When the insect visits the flower, pollinia get entangled in the legs of the insect. When this insect visits other flower, pollinia are transferred.

18.  Salvia or Sage plant : It shows lever mechanism or turn pipe mechanism. Anthers are distractile ; lower lobe is sterile and upper lobe is fertile. The flower is bilabiate and protandrous. The insect sits on the lower lobe of the corolla; the upper fertile lobe of anther touches the body of insect

19. It ruptures and pollen grains are shed on the back of the insect. When this insect enters the other flower, pollination is affected.

20. Ficus sp : Trap Door mechanism in Ficus carica. The receptacle forms a cup having a cavity. The cavity has a pore called ostiole near which male flowers are present. Female flowers are present at the bottom and gall (sterile) flowers are present between these types. The pollinating insect is Blastophaga or gall insect. The insect lays eggs in the bottom, the larvae feed on the ovules of gall flowers. When the young insects crawl out of the inflorescence, their bodies are laden with pollen grains. They enter new hypanthodium and affects the pollination.

21. Ornithophily • Birds are: • agile • long-beaked • visual: see red and yellow colors well • poor “smellers”

22. have nectar hidden by long floral tube • little or no fragrance • no landing platform Flowers are brightly coloured but odourless and produce plenty of nectar and large quantity of pollens e.g., Bombax (red silk cotton), Callistemon (bottle brush), Sterlitzia, Erythrina (coral tree) etc. Honey bird, humming bird and sun bird are common pollinators.

24. Chiropterophily Bats pollinate the flowers of tropical regions. e.g., Anthocephallus (Kadamb), Kigelia (Sausage tree), Adansonia (Baobab Tree).

25. Bat-pollinated flowers • Open at night • Produce lots of pollen and nectar as rewards • White or light-colored • Fragrant (sweet odor) • May be pendant (hang down from branches).