Pollination

POLLINATIONPresented by

SPARTANS

Group membersAMMARA JABEEN

MUHAMMAD KAMRAN

KASHAF FATIMA

KHUBAIB ULHASSAN

Definition

“The process by which plant pollen is transferred from the male reproductiv

e organs to the female reproductive organs to form seeds. In

flowering plants, pollen is transferred from the anther to the stigma, often

by the wind or by insects. In cone-bearing plants, male cones

release pollen that is usually borne by the wind to the ovules of female con

es.’’

General process

Types of pollination

Self pollination:

Self-pollination takes place when the pollen from one flower pollinates the same flower or other flowers of the same individual.

• Autogamy

• Geitonogamy

• Examples: Apricot,Figs,Peaches,Apple and Palm

Importance of self-pollination

Advantages

Less energy is required

May occur without pollinator

Plants spread beyond the range

of suitable pollinators

Less chance of failure of

pollination

Disadvantages

No new species

No evolution

Less resistance to diseases

No new characters

Undesired characters

Cross pollination/allogamy Cross Pollination occur when pollen grains are transferred to a flower from a

different plant.

Further Types :

Abiotic pollination:

Anemophily: pollination by wind

Hydrophily: pollination by water

Examples: coconut, palm, maize, grasses etc.

Biotic pollination:

Biotic pollination is the process of pollination

that requires pollinators like some organisms

that transfer the pollen grain from the anther to

the receptive part or the stigma of the carpel

or pistil.

Entomophily or Insect Pollination: by insects

Zoophily: by vertebrates

Ornithophily or Bird Pollination: by humming

birds, sun birds and honey eaters

Chiroperophily or Bat Pollination: by bats

Anthropophily: by human beings

Examples: Species of Arctium (burdock), Acaena and Galium

aparine

Importance of cross pollination

Advantages

Genetic recombination

Increase in adaptability

More resistant

More seeds are produced

New and more variations

More yield than average

Disadvantages

Plants have to produce large

pollen grains and accessory

structures

Factor of chance

Undesirable characters

Less economical

Spoilage of good character race

Factors of Pollination

Weather

Lack of pollinators

Domesticated pollinators

Insecticides

Light intensity or solar radiations

Floral display size

Flowering plant density

Nectar-sugar concentration

Humidity

wind velocity

Temperature

Artificial mean of pollination

Hand pollination or mechanical pollination

Honey bees

Bumble bees

Electrical vibrator

Need of artificial means

Primary reason is moving of crops from home areas without taking natural

pollinators

Pollinator decline

Monoculture

Hand pollination

Also called mechanical pollination

Used on small scale

For crops having poor pollination

For example : cucurbits

Other reason for hand pollination

For avoiding wasting of

Energy & space for growing male plants

For example: date palm

Pollination by honey bees

Used on large scale

Such as : field crops, orchard or

commercial seed production

Cultured and provide by

pollination management

Bumble bees and electrical vibrators

Used on small scale

Particularly for crops in green

houses

For example: tomatoes in

green houses

IMPORTANCE OF POLLINATION

Reproduce and produce enough seeds for dispersal and propagation

Maintain genetic diversity within a population

Develop adequate fruits to entice seed dispersers

Berries and fruits provide food for wildlife.

Insures reproduction of vegetation in watershed areas.

Helps maintain “balance” of ecological systems by supporting a diversity of

plant species.

Cultural symbolism

moths

butterflies

humming birds

Environmental benefits of pollination

Clean air (carbon cycle)

1. Flowering plants produce breathable oxygen.

2. Levels of carbon dioxide in the atmosphere have been rapidly

increasing due to increased burning of fossil fuels and destruction of

vital forests

3. Pollinators are key to reproduction of wild plants in our fragmented

global landscape

4. Without them, existing populations of plants would decline

Water and Soils

Flowering plants help to

1. purify water

2. prevent erosion

3. foliage buffers the impact of rain as it falls to the earth.

The water cycle depends on plants to return moisture to the atmosphere,

and plants depend on pollinators to help them reproduce.

Cultural importance:

A hummingbird flits among the blossoms of a fireweed.

Native Peoples traditionally recognized the importance of pollinators.

Cultural symbolism

Food plants

Medicinal plants

Plant-based dyes

Problems in pollination

Temperature:

1. Cold weather can delay the development of blossoms.

2. Hot weather can also delay blooms.

No female blossoms:

1. Males usually come first.

2. They come in big numbers and strut their stuff, awaiting the arrival of the ladies.

3. After a while, sometimes several days or more, a few timid females begin to arrive.

Fruit Shrivels and Dies off

1. Pollination did not occur

2. plant stress caused the fruit to abort.

High Temperatures-

1. As temperatures reach the high 80's, the success rate for pollination declines.

2. A heat wave in the 90’s, will result in poor pollination.

Lack of Pollinators:

1. A disease affecting honeybees has devastated their population in many areas.

2. Many new growers will spray insecticides that kill insects and pollinators alike.

3. The result.....no pollination.

Plant Stress:

1. In nature when a plant is under stress, it will not produce fruit Or abort fruit.

2. That stress is caused by:

Water: Too little or too much water.

Soil pH imbalance: pH levels are too high, or too low.

Mineral and/or Nutrients:

1. Too much nitrogen can delay the flower/fruit stage.

2. Phosphorus will promote flowering and fruit set.

3. A range of micro-nutrients are also important.

Insect or disease problems:

1. The plant is struggling to fight off damage from insects or disease.

2. It will not produce flowers and can abort existing fruit.

Climate Changes:

1. Climate change will alter the close relationship between insect pollinators and the plants.

2. Flowering plants migrating north or to cooler result in change of composition of pollinator.

3. According to the observations, bumble bees adapted to cooler temperatures are in decline, while bumble bees adapted to warmer temperatures are expanding their ranges northward.

Pollution, Including Pesticides:

1. Air pollution is a very real problem for bees and other pollinators

2. Light pollution can harm moth pollinators by increasing their susceptibility

to predation by bats or birds when they are attracted to artificial lights at

night.

3. Pesticide misuse and drift from aerial spraying are a major threat to insect

pollinators.

4. Insecticides applied to seeds can contaminate the pollen grains that are

an essential source of food for bees and their young.

Habitat Loss, Degradation, and Fragmentation:

1. Much pollinator habitat has been lost to urban development.

2. Pollinators are habitat-specific, and the loss of habitat that provides sites

for overwintering, foraging for pollen and nectar, or nesting can be

detrimental to these species.

3. Habitat degradation, is another serious concern. For example, the loose,

friable soil required by ground-nesting bees may be trampled by heavy

foot traffic or the use of off-road vehicles.

4. Many pollinators are adversely affected when large habitat are broken

up into smaller by road construction. These habitat fragments may not be

large enough to meet all pollinator needs by themselves,

Solutions of the problems

Cure for high temperature

Cure for no female blossoms

Proper pollination

More pollinators

Release plant stress

To get rich soil

Cure for insects/diseases

Suggestions for pollination

Plant a garden using a native

flowering plants

Provide habitat for egg laying

Avoid or limit pesticide use

Conservative Actions for Pollination

• Conservation of pollinators is the conservation of pollination

• Protection of habitat

• Habitat connectivity

• Plant native species

• Minimize the use of insecticides

• Provide nesting places to pollinators

• Guide your dear one’s about pollination

THANK YOU …

ANY QUESTION???