Unit 2 Plants for Food and Fibre

Plant Reproduction and Breeding Topic 3 Plant Reproduction and Breeding

POS - selective breeding - plant propagation and reproduction  describe life cycles of seed plants, and identify example methods used to ensure their germination, growth and reproduction (e.g.,describe propagation of plants from seeds and vegetative techniques,such ascuttings;conduct a germination study; describe the useof beehives to support pollination)

Brainstorm-How do plants reproduce?

Plant some seeds!

Reproduction Types Sexual Asexual (Vegetative) Selective reproduction: When humans choose characteristics and encourage plants to reproduce Genetic engineering/genetically modified

Selective reproduction What types of features would be desirable? Apples Flowers corn

Asexual Reproduction Method where the new “baby” plant will be genetically identical to the “parent” plant (cloning, dolly the sheep brainpop)

Asexual Reproduction Methods: Problems with Asexual reproduction: Grafting: removal of a branch, attach to a host Cutting: sever the stem, place in water or soil where it will grow roots Layering: bury a piece of stem, new roots will grow Problems with Asexual reproduction: Vulnerable to disease as there is no genetic variation

Cutting

Grafting

Layering

Strawberry runners

Bulbs

Trembling Aspens-asexual

Sexual Reproduction Pollination: is a type of reproduction where the new plant will be a combination of both parent plants, and genetically unique Methods: Cones (gymnosperms-evergreens) Flowers (angiosperms) Benefit: able to adapt to changes in the environment

Agricultural benefit! Farmers purposely keep beehives in their fields to encourage pollination of their crops

Pollination By wind By birds, insects

Male + Female cones

Flowers

Parts of a flower- pg 122

Germination

Assignment Draw the diagram of the parts of a flower on page 122 in your journal Of pollination page 124 Of a seed pg 125 Germination pg 128