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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???