LO 1.0 - 1.2 - Outline the principles of plant propagation Flashcards
Plant Propagation is the process of creating new plants using a variety of means. Name them…
Plant Propagation
- Seed (Sexual)
- Cuttings
- Division
- Layering
- Grafting
- Micro propagation
Why create new plants ?
- For extra garden plants
- For friends, family & community
- For sale/commercial use
- For interest & knowledge
Reconsider
Propagation methods range greatly from simple to sophisticated
- Pot with compost & plastic bag
- Geranium in water
- Fog System
- Micro prop system
Layering, Cutting, Seed, Micropropagation, Division. These propagation methods suit one plant type better than others. Match them up.
- Grass –
- Fuchsia –
- Daffodil –
- Daphne bholua –
- Most plants –
With Seeds 6 things to rememeber.
- Sexual reproduction within species
- Genetic recombination occurs
- Different characteristics from parents
- Plants may not produce seed until mature
- Some plants do not produce seed
- Some plants produce infertile seed
These are the main points of Asexual Propagation.
- Plants are produced by using material from a single parent
- No exchange of genetic material
- Production of plants identical to parent
- Vegetative / Clonal propagation
- Cuttings
- Grafting
- Division
- Layering
- Micro propagation
Seed Production
Some points to remember about…
- Genetic diversity
- Seed is an embryonic plant - Embryo - Seed coat
- Food reserve
- Product of Ovule of both Gymnosperms and Angiosperms
- Occurs post fertilisation
- Embryo develops from zygote
Seed Production
Compare Angiosperms and Gymnosperms seeds.
Angiosperms (enclosed seed)
- Enclosed by hard or fleshy coat called fruit.
Gymnosperms (naked seed)
- No special structures develop to cover seed.
- In time cone scales grow to cover some seed.
Seed Production
Seed vary greatly in size
- Orchid seed are tiny (1million seed per gram)
- Use fungi (Mycorrhiza) for nutrition
- Coco de Mer is largest seed (20Kgs approx.)
Seed Collection
Some points to remember about…
- Collect when ready • Colour change
- Place seed on sheets of blotting paper if excessively wet.
- Place seed in paper bags if collected in dry conditions
- Allow to dry
Seed Collection
What are suitable conditions for storing seeds?
- Ensure storage in suitable conditions
- Dry
- Cool
- Vermin free
- Breathable
Seed Origin
2 quotes regarding seed origin.
“The geographical source or place of origin from which a given lot of seed or plants was collected; the material from such a source or origin; often restricted to imply material from a specified race”
(Empire Forestry Association, 1953)
“The original geographic source of a lot of seed (or pollen).”
(Wright, 1962)
Seed Provenance
What is it?
The geographical area and environment to which the parent trees, etc. are native, and within which their genetic constitution has been developed through natural selection.
What are some advantages of Seed Propagation?
- Sometimes possible/practical way of commercially growing.
- Seed is important in developing new cultivars
- May raise chance seedlings with superior characteristics
- Seed raised trees generally live longer
- Seed raised can be hardier
- Rootstocks are raised from seed
- Seed can produce virus free plants
- Seed are a convenient method of storing plants
Disadvantages of Seed Propagation.
- Seed are not usually true to type
- Not uniform in - Growth - Flowering - Fruit - Yield
- Plants can take longer to flower and fruit.
- Trees are difficult to manage in orchards - when using rootstocks
Asexual Methods
Layering
Layering
- Stems, which are still attached to the parent plant, may form roots naturally or may be helped by wounding
- Plants are cut from the parent plant after a season to form a new set of plants clonally identically to the single parent.
Asexual Methods
Division
Division
- Plants form around the parent and are detached from the parent to create new plants which are clonally identical to the single parent.
Asexual Methods
Grafting
Grafting
- The joining together of two plants, one a root stock and two a scion, to produce a novel plant the scion of which is identical to the single parent
- The root stock may be from seed or may be clonal
Asexual Methods
Micro propagation
Micro propagation
- Rapid multiplication of plants from parent plant using modern lab based tissue culture methods.
- Plants are clonally identically to the single parent
Genetic Outcomes
of Sexual Propagation and Asexual Propagation.
- Sexual Propagation • It impacts by allowing future generations of plants to mix in an almost infinite range of phenotypes
- Asexual Propagation • It impacts on genetic variation by limiting future genetic change to mutations in the form of sports etc
