1. Flowers

2. Pollination syndromes
among the phloxes

3. Butterfly and Moth Pollination
Butterfly and moth flowers similar to bee flowers because moths and butterflies also guided to flowers by combination of sight and smell
Some butterflies can see red, so often have red or orange color for flower
Nectary is often at bottom of long, slender corolla tube or a nectar spur - only accessible to long sucking probocis of moths and butterflies
Nectar is copious, but not so concentrated - often 25% sugar
Moths are nocturnal so many of their flowers emit heavy fragrance at night, often pale or white in color - scent is sweet and penetrating

4. Erysimum – butterfly pollinated

5. Episcia – moth pollinated

6. Bird Pollination
Bird pollinated flowers produce copious, thin nectar - often about 25% sugar, often very high in sucrose - may actually drip with nectar
Usually have little odor because birds have poor sense of smell
Birds see red and bird pollinated flowers often very colorful with reds and yellows - red columbine, fuchsia, passion flower, hibicus, poinsettia, many cactus and orchids
The flowers are usually large or part of large inflorescence
Nectar usually held in long tubes that other animals can’t reach

7. Hummingbird pollination

8. Ipomopsis aggregata – hummingbird pollinated

9. Greater double-collared sunbird

10. Proteus – pollinated by perching birds

11. Bat Pollination
About 250 species of bat (25% of all bats) include some pollen, nectar or fruit in their diet - many pollinate flowers as part of their feeding
Bat flowers are similar to bird flowers - large, strong flower which produces copious nectar - Often dull colored because open at night - may only open at night
Often have very strong fermenting or fruitlike odors, may be musky odors too
Bat flowers often hang down below foliage to enable bats to easily get to the flower
Banana, mango, sisal and kapok flowers pollinated by bats

12. Bat pollination

13. Wind Pollination
Usually have dull colors, relatively odorless, do not produce nectar, petals small or absent, sexes often separated
Wind pollinated flowers are most common in temperate areas where large stands of single species of plant occur
With trees, wind pollination occurs in spring before leaves have emerged - usually have well exposed stamens to shed pollen to wind and stigma also exposed - often with feathery outgrowths to catch pollen
Often the plants have various mechanisms to promote out-crossing - separate sexes - dioecious - willows, poplars
unisexual flowers on same tree - monoecious - oaks, birches
Self-incompatible - grasses
Flowers are typically small, have single ovule per flower - however have many flowers borne in inflorescences and multiple inflorescences

14. Box elder – wind pollinated – female left, male right

15. Wild Oats – Avena fatua

16. Wild oat flower – close up

17. Cottonwood Catkins
Male
Female

18. Why Pollination?

19. Why Pollination?
Plants engage in pollination in order to ensure successful sexual reproduction
Then – Why Sex?
The benefits of sexual reproduction are that it enables the introduction of novel genetic combinations of DNA
This creates potential for plants to develop new genetic combinations which may allow increased survival, reproduction and thus fitness – producing more offspring

20. Sexual reproduction introduces variation via three steps:
1. meiosis forms haploid cells with different combinations of chromosomes
2. genetic recombination occurs during meiosis via crossing over
3. fusion of gametes (eggs and sperm) from haploid cells to form new zygote

23. Pollination in Plant Breeding

26. Double Fertilization
At double fertilization, several processes are initiated:
the primary endosperm nucleus divides forming the endosperm;
the zygote develops into the embryo;
the integuments develop into the seed coat;
the ovary and related structures develop into the fruit

28. Embryo Development
Early embryo development is similar in dicots and monocots - at first the embryo is a spherical body - however, differences appear when the cotyledons develop - the dicot has two cotyledons and the monocot has one cotyledon

29. Endosperm and Cotyledons
The primary endosperm nucleus divides mitotically to form the endosperm - the endosperm tissue will provide food to the developing embryo and in many cases, to the young seedling too
In many dicots and some monocots, the endosperm tissues are absorbed by the developing embryo before the seed becomes dormant - then the nutrition is stored in the cotyledons - peas, beans

31. Gymnosperm Seeds
In gymnosperms like this pine, the food for the seed comes from maternal tissue (the gametophyte)

32. Ovary and Ovule Development
As the ovule develops into the seed, the ovary develops into the fruit
As this happens the ovary wall thickens to form a pericarp - the pericarp often has distinct layers - exocarp, mesocarp and endocarp or just exocarp and endocarp - the layers are easiest to see on fleshy fruits

33. Fruit Layers
1. Endocarp 2. Seed 3. Mesocarp 4. Exocarp 1, 3, and 4 together make up the pericarp.

35. Fruits
A fruit may be defined as a matured ovary. In some plants the fruit may include other flower parts that are fused to the ovary. True fruits develop from a single pistil. A flower with one or more simple pistils produces a corresponding number of fruits. A compound pistil develops into one fruit but may split at maturity into a number of pieces that often corresponds to the number of carpels in the pistil (like a blackberry or pineapple).

36. Note:
D should be Samara;
E should be Achene

38. Note – missing
Pepo and hesperidium

39. Apples and Pears

40. Strawberry – flower and fruit

41. Seed Dispersal

42. Seed Dispersal Distances

45. Animal Seed Dispersal Shimba Hills, Kenya

46. Seed Dispersal by Wind

47. Seed Dispersal by Water - Coconut

48. Poppy – shaking in breeze
Seed Dispersal by Self
Poppy – shaking in breeze
Explosive

49. Hitch-hiking

50. Human Seed Dispersal

51. Limiting Seed Dispersal
In violets there are two kinds of flowers:
chasmogamous flowers that open in the normal way and are insect pollinated - these seeds disperse far away
closed cleistogamous flowers that never open and reproduce by selfing - these seeds never disperse very far - the cleistogamous flowers form later in the summer

52. Violet
flower
types

53. More limits to Dispersal
Peanuts limit their dispersal even further because their cleistogamous seeds are produced by underground flowers - these are called amphicarpic flowers and seeds - these seeds clearly don’t disperse

54. Peanut – Amphicarpic Seeds

55. Dispersal by Clonal Growth – Black Locust